OXYGENHUB
# e226a6cc2f71 oxygen / crates / oxy-core / src / repo / snapshot.rs
108.3 KiB · Rust · last changed Commit takes a status's snapshot from the cache; the stat check lends its stats to the snapshot (refs #41) 1 month ago source blame history raw
98286406 Andy McCall ↶ 1 
//! Working-copy snapshots, commits, and the change builder (spec §12.3).
2
3 
use super::*;
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use crate::objects::AtomRef;
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6 
#[derive(Clone, Copy, Debug, PartialEq, Eq)]
7 
pub enum ChangeStatus {
8 
    Added,
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    Modified,
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    Removed,
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    /// Moved from another path (detected by similarity, tracked as a placement change).
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    Renamed,
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    ModeChanged,
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    /// The file is conflicted in the base state and still contains conflict markers.
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    ConflictEdited,
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    /// The file was conflicted in the base state and the working copy resolves it.
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    Resolved,
18 
}
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20 
/// Lines that mark a conflict region in a materialized file (spec §9.5).
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pub fn has_conflict_markers(content: &[u8]) -> bool {
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    split_lines(content).iter().any(|l| {
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        l.starts_with(b"<<<<<<< oxy conflict")
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            || l.starts_with(b"======= oxy conflict")
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            || l.starts_with(b">>>>>>> oxy conflict")
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    })
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}
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#[derive(Clone, Debug, PartialEq, Eq)]
30 
pub struct PathStatus {
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    pub path: String,
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    pub status: ChangeStatus,
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}
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/// Operations of a change built from the working directory against a base.
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pub(crate) struct BuiltChange {
37 
    pub tree_ops: Vec<TreeOp>,
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    pub edits: Vec<Edit>,
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    pub contributors: Vec<ChangeHash>,
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    pub resolves: bool,
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    pub statuses: Vec<PathStatus>,
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    /// The stored blob of every opaque path, for the manifest's stat cache.
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    pub blobs: HashMap<String, ObjectRef>,
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}
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/// Result of snapshotting the working copy.
47 
pub struct SnapshotResult {
48 
    pub wc_hash: ChangeHash,
49 
    pub wc: Change,
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    /// The base state (closure of the working-copy change's dependencies).
51 
    pub base: State,
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    pub base_snapshot: Snapshot,
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    pub statuses: Vec<PathStatus>,
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    /// Whether the snapshot rewrote the working-copy change.
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    pub changed: bool,
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    /// Whether the working copy resolves conflicts of its base (spec §9.6).
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    pub resolves: bool,
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    /// Changes that contributed to the conflicts being resolved.
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    pub contributors: Vec<ChangeHash>,
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    /// The `.oxyattributes` in force on disk, from the files the walk read.
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    pub(crate) attributes: crate::attributes::Attributes,
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    /// Folders holding a repository of their own (`.git` or `.oxy`) that
63 
    /// are not subrepos, so nothing in them is tracked (oxygen#43).
64 
    pub untracked_nested: Vec<String>,
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}
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67 
pub fn is_binary(content: &[u8]) -> bool {
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    content[..content.len().min(BINARY_SNIFF)].contains(&0)
69 
}
70
71 
impl Repo {
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    /// Diff the files on disk against `base` and build the operations of a
73 
    /// change from `base` to the working directory. `reuse` maps paths to the
74 
    /// NodeIds an earlier version of the same change assigned to new paths.
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    pub(crate) fn build_against(
76 
        &self,
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        base: &State,
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        base_snapshot: &Snapshot,
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        reuse: HashMap<String, (NodeId, NodeKind)>,
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    ) -> Result<BuiltChange> {
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        let mut fs_entries =
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            self.walk_working_copy_with(None, &Self::tracked_kinds(base_snapshot), None)?;
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        self.platform_normalize(&mut fs_entries, base_snapshot);
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        self.build_from_entries(base, base_snapshot, reuse, &fs_entries)
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    }
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    /// Read the working copy as the platform left it (spec §7.7): without
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    /// executable bits a file keeps the bit it has in the base, and without
89 
    /// symbolic links a plain file where the base has a symlink is that
90 
    /// symlink, written out as its target, not a new file.
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    fn platform_normalize(&self, entries: &mut BTreeMap<String, FsEntry>, base: &Snapshot) {
92 
        let p = self.platform;
93 
        if p.exec_bits && p.symlinks {
94 
            return;
95 
        }
96 
        for (path, e) in entries.iter_mut() {
97 
            let Some(f) = base.files.get(path) else {
98 
                continue;
99 
            };
100 
            if !p.symlinks && f.kind == NodeKind::Symlink && e.kind == NodeKind::File {
101 
                e.kind = NodeKind::Symlink;
102 
                e.exec = false;
103 
            }
104 
            if !p.exec_bits && f.kind == NodeKind::File && e.kind == NodeKind::File {
105 
                e.exec = f.mode.exec;
106 
            }
107 
        }
108 
    }
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    /// Like `build_against`, for files given in memory (imports).
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    pub(crate) fn build_from_entries(
112 
        &self,
113 
        base: &State,
114 
        base_snapshot: &Snapshot,
115 
        reuse: HashMap<String, (NodeId, NodeKind)>,
116 
        fs_entries: &BTreeMap<String, FsEntry>,
117 
    ) -> Result<BuiltChange> {
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        self.build_from_entries_resolving(base, base_snapshot, reuse, fs_entries, &HashSet::new())
119 
    }
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121 
    /// Like `build_from_entries`, settling the replace conflicts of the
122 
    /// opaque files in `resolve` to their content (spec §9.3, §9.6): a
123 
    /// caller that knows the user chose it, such as the hub's resolver. A
124 
    /// snapshot never settles one on its own, since a checkout writes one
125 
    /// candidate at the path.
126 
    pub(crate) fn build_from_entries_resolving(
127 
        &self,
128 
        base: &State,
129 
        base_snapshot: &Snapshot,
130 
        reuse: HashMap<String, (NodeId, NodeKind)>,
131 
        fs_entries: &BTreeMap<String, FsEntry>,
132 
        resolve: &HashSet<String>,
133 
    ) -> Result<BuiltChange> {
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        self.build_from_entries_with(
135 
            base,
136 
            base_snapshot,
137 
            reuse,
138 
            fs_entries,
139 
            resolve,
140 
            Scope::default(),
141 
        )
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    }
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144 
    /// `build_from_entries` whose new nodes take identifiers derived from
145 
    /// `seed` and their paths instead of random ones, so the same input
146 
    /// always builds the same change (a Git import, spec §23).
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    ///
148 
    /// With `dir_needed`, the snapshot and entries hold only the paths the
149 
    /// import touches (and the directories a removal may leave empty); a
150 
    /// directory stays while `dir_needed` says the new tree has something
151 
    /// under it.
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    pub(crate) fn build_from_entries_seeded(
153 
        &self,
154 
        base: &State,
155 
        base_snapshot: &Snapshot,
156 
        fs_entries: &BTreeMap<String, FsEntry>,
157 
        seed: [u8; 32],
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        dir_needed: Option<&dyn Fn(&str) -> bool>,
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    ) -> Result<BuiltChange> {
160 
        self.build_from_entries_with(
161 
            base,
162 
            base_snapshot,
163 
            HashMap::new(),
164 
            fs_entries,
165 
            &HashSet::new(),
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            Scope {
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                seed: Some(seed),
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                dir_needed,
169 
            },
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        )
171 
    }
172
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    /// `build_from_entries` for a snapshot most of whose files are known
174 
    /// unchanged (oxygen#41): only the paths that may differ are built
175 
    /// (files read rather than known unchanged, base files gone from disk,
176 
    /// and the directories those may leave empty), against a snapshot of
177 
    /// just those, so a large tree with a few edits costs what they touch.
178 
    fn build_changed_only(
179 
        &self,
180 
        base: &State,
181 
        base_snapshot: &Snapshot,
182 
        reuse: HashMap<String, (NodeId, NodeKind)>,
183 
        fs_entries: &BTreeMap<String, FsEntry>,
184 
    ) -> Result<BuiltChange> {
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        let pick = crate::timing::phase("snapshot:   of which picking the changed");
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        // A file known unchanged may still have changed mode: that alters
187 
        // neither its size nor its time.
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        let changed: BTreeMap<String, FsEntry> = join(fs_entries, &base_snapshot.files)
189 
            .filter_map(|(p, e, f)| {
190 
                let e = e?;
191 
                (!e.unchanged || f.is_none_or(|f| f.kind != e.kind || f.mode.exec != e.exec))
192 
                    .then(|| (p.clone(), e.clone()))
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            })
194 
            .collect();
195 
        let mut files: BTreeMap<String, crate::state::FileState> = BTreeMap::new();
196 
        for p in changed.keys() {
197 
            if let Some(f) = base_snapshot.files.get(p) {
198 
                files.insert(p.clone(), f.clone());
199 
            }
200 
        }
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        // Paths the base has and the disk does not.
202 
        let gone = join(&base_snapshot.files, fs_entries)
203 
            .filter_map(|(p, f, e)| (e.is_none()).then_some((p, f?)));
204 
        for (p, f) in gone {
205 
            if f.kind == NodeKind::Dir {
23ff1288 Andy McCall ↶ 206 
                continue;
207 
            }
208 
            files.insert(p.clone(), f.clone());
209 
            let mut end = p.len();
210 
            while let Some(i) = p[..end].rfind('/') {
211 
                let dir = &p[..i];
212 
                if files.contains_key(dir) {
213 
                    break;
214 
                }
215 
                if let Some(d) = base_snapshot.files.get(dir) {
216 
                    files.insert(dir.to_string(), d.clone());
217 
                }
218 
                end = i;
219 
            }
220 
        }
221 
        let part = Snapshot {
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            tree: base_snapshot.tree.clone(),
223 
            files,
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            unrendered: BTreeSet::new(),
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        };
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        drop(pick);
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        let _build = crate::timing::phase("snapshot:   of which building the change");
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        // Whether anything on disk is under `dir`.
229 
        let dir_needed = |dir: &str| {
230 
            let prefix = format!("{dir}/");
231 
            fs_entries
232 
                .range(prefix.clone()..)
233 
                .next()
234 
                .is_some_and(|(k, _)| k.starts_with(&prefix))
235 
        };
236 
        self.build_from_entries_with(
237 
            base,
238 
            &part,
239 
            reuse,
240 
            &changed,
241 
            &HashSet::new(),
242 
            Scope {
243 
                seed: None,
244 
                dir_needed: Some(&dir_needed),
245 
            },
246 
        )
247 
    }
248
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    fn build_from_entries_with(
250 
        &self,
251 
        base: &State,
252 
        base_snapshot: &Snapshot,
253 
        reuse: HashMap<String, (NodeId, NodeKind)>,
254 
        fs_entries: &BTreeMap<String, FsEntry>,
255 
        resolve: &HashSet<String>,
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        scope: Scope,
dfb23a3a Andy McCall ↶ 257 
    ) -> Result<BuiltChange> {
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        let Scope { seed, dir_needed } = scope;
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        let mut laps = crate::timing::Laps::start();
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        // Attributes come from the files being committed, so a new
261 
        // `.oxyattributes` applies to the same change that adds it.
262 
        let attrs = crate::attributes::Attributes::from_files(
75167672 Andy McCall 263 
            fs_entries
264 
                .iter()
265 
                .filter(|(p, _)| p.as_str() == ".oxyattributes" || p.ends_with("/.oxyattributes"))
266 
                .map(|(p, e)| (p.as_str(), e.content.as_slice())),
cdb5beba Andy McCall ↶ 267 
        );
268 
        let mut b = ChangeBuilder::new(base, base_snapshot, reuse).with_attributes(attrs);
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        b.resolve = resolve.clone();
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        b.node_seed = seed;
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        laps.lap("build: builder");
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        // Rename detection (spec §7.1, §23): a removed file and an added file
273 
        // of the same kind whose contents are at least half alike become one
274 
        // move of the same node, so identity survives across the rename.
275 
        let renames = detect_renames(base_snapshot, fs_entries, |p| self.in_scope(p));
75167672 Andy McCall 276 
        let renamed_from: HashMap<&str, &str> = renames
277 
            .iter()
278 
            .map(|(old, new)| (new.as_str(), old.as_str()))
279 
            .collect();
280 
        let renamed_to: HashMap<&str, &str> = renames
281 
            .iter()
282 
            .map(|(old, new)| (old.as_str(), new.as_str()))
283 
            .collect();
2306a4d2 Andy McCall ↶ 284 
        laps.lap("build: renames");
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        for (path, fs_entry) in fs_entries {
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            match base_snapshot.files.get(path) {
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                None => match renamed_from.get(path.as_str()) {
75167672 Andy McCall 288 
                    Some(old) => {
289 
                        b.move_path(self, old, path, fs_entry, &base_snapshot.files[*old])?
290 
                    }
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                    None => b.add_path(self, path, fs_entry)?,
292 
                },
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                Some(expected) => b.update_path(self, path, fs_entry, expected)?,
294 
            }
295 
        }
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        laps.lap("build: paths");
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        // A directory stays while anything under it exists or is out of
298 
        // scope: the directories above each such path, gathered once.
299 
        let mut needed_dirs: HashSet<&str> = HashSet::new();
300 
        fn parents_of<'a>(p: &'a str, set: &mut HashSet<&'a str>) {
301 
            let mut end = p.len();
302 
            while let Some(i) = p[..end].rfind('/') {
303 
                if !set.insert(&p[..i]) {
304 
                    break;
305 
                }
306 
                end = i;
307 
            }
308 
        }
309 
        for p in fs_entries.keys() {
310 
            parents_of(p, &mut needed_dirs);
311 
        }
312 
        for p in base_snapshot.files.keys() {
313 
            if !self.in_scope(p) {
314 
                parents_of(p, &mut needed_dirs);
315 
            }
316 
        }
98286406 Andy McCall ↶ 317 
        for (path, expected) in &base_snapshot.files {
75167672 Andy McCall 318 
            if fs_entries.contains_key(path)
319 
                || !self.in_scope(path)
320 
                || renamed_to.contains_key(path.as_str())
321 
            {
98286406 Andy McCall ↶ 322 
                continue;
323 
            }
2306a4d2 Andy McCall ↶ 324 
            let still_needed = expected.kind == NodeKind::Dir
325 
                && match dir_needed {
326 
                    Some(f) => f(path),
327 
                    None => needed_dirs.contains(path.as_str()),
328 
                };
98286406 Andy McCall ↶ 329 
            if !still_needed {
330 
                b.remove_path(path, expected);
331 
            }
332 
        }
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        laps.lap("build: removals");
a87c7b9d Andy McCall ↶ 334 
        if seed.is_some() {
335 
            b.retire_stray_placements();
336 
        }
2306a4d2 Andy McCall ↶ 337 
        laps.lap("build: stray placements");
614541c3 Andy McCall ↶ 338 
        let mut statuses = b.statuses;
339 
        statuses.sort_by(|a, b| a.path.cmp(&b.path));
75167672 Andy McCall 340 
        Ok(BuiltChange {
341 
            tree_ops: b.tree_ops,
342 
            edits: b.edits,
343 
            contributors: b.contributors.into_iter().collect(),
344 
            resolves: b.resolves,
345 
            statuses,
346 
            blobs: b.blobs,
347 
        })
614541c3 Andy McCall ↶ 348 
    }
98286406 Andy McCall ↶ 349
c07e0e7d Andy McCall ↶ 350 
    /// Store a change and, when `core.sign = change` and we are its author,
351 
    /// sign it. A rewritten change by another author is stored unsigned: only
352 
    /// its author (or a delegate) can vouch for it.
614541c3 Andy McCall ↶ 353 
    pub(crate) fn store_signed(&self, change: &Change) -> Result<ChangeHash> {
c07e0e7d Andy McCall ↶ 354 
        let ours = change.author == self.author();
355 
        if self.config.sign_changes && ours && self.secret_key()?.is_none() {
614541c3 Andy McCall ↶ 356 
            return fail("core.sign is \"change\" but no secret key is available for author.key");
357 
        }
358 
        let hash = self.store.put_change(change)?;
c07e0e7d Andy McCall ↶ 359 
        if self.config.sign_changes && ours {
614541c3 Andy McCall ↶ 360 
            self.sign_change(&hash)?;
361 
        }
362 
        Ok(hash)
363 
    }
364
365 
    /// Snapshot the working copy into the working-copy change (spec §12.3).
cc7a0056 Andy McCall ↶ 366 
    /// The result carries the full base state and its whole rendering.
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    pub fn snapshot(&self, command: &str) -> Result<SnapshotResult> {
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        self.snapshot_as(command, false, false)
cc7a0056 Andy McCall ↶ 369 
    }
370
371 
    /// Snapshot the working copy as [`Repo::snapshot`] does, for commands
8ab265dc Andy McCall ↶ 372 
    /// that need its statuses, conflicts and base history, and the graphs
373 
    /// of the files it changes: status, log, show, commit, diff, hunks and
374 
    /// discard. Text files known unchanged since the last manifest are
cc7a0056 Andy McCall ↶ 375 
    /// neither read nor rendered: the result's `base` is a history-only
376 
    /// state without their graphs, and its `base_snapshot` lists them in
8ab265dc Andy McCall ↶ 377 
    /// `unrendered` with empty bytes. They are never conflicted, and no
378 
    /// change the working copy makes touches them.
cc7a0056 Andy McCall ↶ 379 
    pub fn snapshot_status(&self, command: &str) -> Result<SnapshotResult> {
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        self.snapshot_as(command, true, false)
cc7a0056 Andy McCall ↶ 381 
    }
382
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    /// `snapshot_as`; `force_manifest` writes the manifest even where a
384 
    /// status would not bother (an edited file is read next time whatever
385 
    /// it says), for a commit, after which that file is unchanged.
386 
    fn snapshot_as(
387 
        &self,
388 
        command: &str,
389 
        partial: bool,
390 
        force_manifest: bool,
391 
    ) -> Result<SnapshotResult> {
4e88e774 Andy McCall ↶ 392 
        let _lock = self.lock_snapshot()?;
8f10a07a Andy McCall ↶ 393 
        let batch = self.store.begin_batch()?;
f9466021 Andy McCall ↶ 394 
        let result = self.snapshot_locked(command, partial, force_manifest);
8f10a07a Andy McCall ↶ 395 
        batch.finish()?;
396 
        result
397 
    }
398
f9466021 Andy McCall ↶ 399 
    fn snapshot_locked(
400 
        &self,
401 
        command: &str,
402 
        partial: bool,
403 
        force_manifest: bool,
404 
    ) -> Result<SnapshotResult> {
0bdc3f91 Andy McCall ↶ 405 
        let _all = crate::timing::phase("snapshot");
614541c3 Andy McCall ↶ 406 
        let (op_ref, op) = self.head_op()?;
407 
        let (old_hash, old_wc) = self.working_copy()?;
cc7a0056 Andy McCall ↶ 408 
        // The base's history first: its graph keys say which files the
409 
        // manifest already knows equal to it.
410 
        let mut base = {
411 
            let _t = crate::timing::phase("snapshot: load base history");
f9575918 Andy McCall ↶ 412 
            self.load_state_indexed(&old_wc.deps)?
0bdc3f91 Andy McCall ↶ 413 
        };
d0d52107 Andy McCall ↶ 414 
        let view = {
415 
            let _t = crate::timing::phase("snapshot: tree view");
416 
            base.tree().view()
417 
        };
8b276e01 Andy McCall ↶ 418 
        let manifest = {
419 
            let _t = crate::timing::phase("snapshot: read manifest");
420 
            self.read_manifest()?.map(|(_, _, m)| m)
421 
        };
cc7a0056 Andy McCall ↶ 422 
        let tracked: BTreeMap<String, (NodeKind, Option<ObjectRef>)> = {
423 
            let _t = crate::timing::phase("snapshot: tracked paths");
36e51aa8 Andy McCall ↶ 424 
            // In the view's path order, so the map is built without searching.
425 
            view.entries
426 
                .iter()
427 
                .filter(|(_, e)| e.kind != NodeKind::Dir)
428 
                .map(|(p, e)| {
429 
                    let blob = if e.kind != NodeKind::File || e.mode.opaque {
430 
                        base.live_blobs(&e.node).first().copied()
431 
                    } else {
432 
                        None
433 
                    };
434 
                    (p.clone(), (e.kind, blob))
435 
                })
436 
                .collect()
cc7a0056 Andy McCall ↶ 437 
        };
992467d3 Andy McCall ↶ 438 
        // A text file's graph key, worked out when the walk asks for it.
1966f5db Andy McCall ↶ 439 
        let key_of = |p: &str| -> Option<[u8; 32]> {
992467d3 Andy McCall ↶ 440 
            let e = view.entries.get(p)?;
441 
            if e.kind != NodeKind::File || e.mode.opaque {
442 
                return None;
443 
            }
1966f5db Andy McCall ↶ 444 
            base.graph_key(&e.node)
992467d3 Andy McCall ↶ 445 
        };
cc7a0056 Andy McCall ↶ 446 
        let mut fs_entries = {
447 
            let _t = crate::timing::phase("snapshot: read working copy");
992467d3 Andy McCall ↶ 448 
            self.walk_working_copy_with(manifest.as_deref(), &tracked, Some(&key_of))?
cc7a0056 Andy McCall ↶ 449 
        };
992467d3 Andy McCall ↶ 450 
        // The keys of the files read, before building graphs drops them: a
451 
        // file found equal to its base rendering keeps its key.
1966f5db Andy McCall ↶ 452 
        let keys: HashMap<String, [u8; 32]> = fs_entries
992467d3 Andy McCall ↶ 453 
            .iter()
454 
            .filter(|(_, e)| !e.unchanged && e.kind == NodeKind::File)
455 
            .filter_map(|(p, _)| Some((p.clone(), key_of(p)?)))
456 
            .collect();
0bdc3f91 Andy McCall ↶ 457 
        let base_snapshot = {
cc7a0056 Andy McCall ↶ 458 
            let _t = crate::timing::phase("snapshot: load and render base");
459 
            if partial {
d616faf5 Andy McCall ↶ 460 
                let sets = crate::timing::phase("snapshot:   of which choosing graphs");
461 
                // Every file but those on disk known unchanged.
462 
                let need: Vec<(&str, NodeId)> = join(&view.entries, &fs_entries)
463 
                    .filter_map(|(p, v, f)| {
464 
                        let v = v?;
465 
                        (v.kind == NodeKind::File && !f.is_some_and(|f| f.unchanged))
466 
                            .then_some((p.as_str(), v.node))
467 
                    })
cc7a0056 Andy McCall ↶ 468 
                    .collect();
d616faf5 Andy McCall ↶ 469 
                let render: std::collections::HashSet<&str> =
470 
                    need.iter().map(|(p, _)| *p).collect();
471 
                let need: Vec<NodeId> = need.iter().map(|(_, n)| *n).collect();
472 
                drop(sets);
d0990c2b Andy McCall ↶ 473 
                {
474 
                    let _t = crate::timing::phase("snapshot:   of which building graphs");
475 
                    self.load_graphs_of(&mut base, &need)?;
476 
                }
477 
                let _t = crate::timing::phase("snapshot:   of which rendering");
d616faf5 Andy McCall ↶ 478 
                base.materialize_only(&render)
cc7a0056 Andy McCall ↶ 479 
            } else {
480 
                self.load_all_graphs(&mut base)?;
481 
                base.materialize()
482 
            }
0bdc3f91 Andy McCall ↶ 483 
        };
614541c3 Andy McCall ↶ 484
485 
        // Reuse the NodeIds the previous working-copy version assigned to new
486 
        // paths, so an unchanged working copy hashes identically (spec §12.3).
487 
        let reuse = added_node_paths(&old_wc, &base_snapshot);
c863c7a7 Andy McCall ↶ 488 
        self.platform_normalize(&mut fs_entries, &base_snapshot);
0bdc3f91 Andy McCall ↶ 489 
        let built = {
490 
            let _t = crate::timing::phase("snapshot: diff against base");
23ff1288 Andy McCall ↶ 491 
            if partial && self.config.sparse_paths.is_empty() {
492 
                #[cfg(test)]
493 
                let full =
494 
                    self.build_from_entries(&base, &base_snapshot, reuse.clone(), &fs_entries)?;
495 
                let built = self.build_changed_only(&base, &base_snapshot, reuse, &fs_entries)?;
496 
                #[cfg(test)]
497 
                {
498 
                    // New nodes take random identifiers: compare them by
499 
                    // order of appearance.
500 
                    let norm = |b: &BuiltChange| {
501 
                        let text = format!("{:?} {:?} {:?}", b.tree_ops, b.edits, b.statuses);
502 
                        let mut seen: Vec<String> = Vec::new();
503 
                        let mut out = String::new();
504 
                        let mut rest = text.as_str();
505 
                        while let Some(i) = rest.find("NodeId(") {
506 
                            out.push_str(&rest[..i]);
507 
                            let end = i + rest[i..].find(')').unwrap() + 1;
508 
                            let id = rest[i..end].to_string();
509 
                            let n = seen.iter().position(|x| *x == id).unwrap_or_else(|| {
510 
                                seen.push(id);
511 
                                seen.len() - 1
512 
                            });
513 
                            out.push_str(&format!("N{n}"));
514 
                            rest = &rest[end..];
515 
                        }
516 
                        out.push_str(rest);
517 
                        out
518 
                    };
519 
                    assert_eq!(
520 
                        norm(&built),
521 
                        norm(&full),
522 
                        "a changed-only build is the full one"
523 
                    );
524 
                }
525 
                built
526 
            } else {
527 
                self.build_from_entries(&base, &base_snapshot, reuse, &fs_entries)?
528 
            }
0bdc3f91 Andy McCall ↶ 529 
        };
cc7a0056 Andy McCall ↶ 530 
        // Text files found equal to an unconflicted base rendering keep its
531 
        // graph key, so the next snapshot need not read or render them.
532 
        {
533 
            let changed: HashSet<&str> = built.statuses.iter().map(|s| s.path.as_str()).collect();
534 
            for (p, e) in fs_entries.iter_mut() {
535 
                if e.unchanged || e.kind != NodeKind::File || changed.contains(p.as_str()) {
536 
                    continue;
537 
                }
538 
                e.graph_key = match base_snapshot.files.get(p).map(|f| &f.content) {
539 
                    Some(FileContent::Text {
540 
                        bytes,
541 
                        materialized,
40a40bb7 Andy McCall ↶ 542 
                    }) if !materialized.is_conflicted() && *bytes == *e.content => {
1966f5db Andy McCall ↶ 543 
                        keys.get(p).copied()
cc7a0056 Andy McCall ↶ 544 
                    }
545 
                    _ => None,
546 
                };
547 
            }
548 
        }
614541c3 Andy McCall ↶ 549
98286406 Andy McCall ↶ 550 
        let mut wc = Change {
6f8aeb99 Andy McCall ↶ 551 
            version: crate::objects::CHANGE_VERSION,
98286406 Andy McCall ↶ 552 
            change_id: old_wc.change_id,
553 
            deps: vec![],
554 
            author: self.author(),
555 
            hlc: old_wc.hlc,
556 
            message: old_wc.message.clone(),
614541c3 Andy McCall ↶ 557 
            tree_ops: built.tree_ops,
558 
            edits: built.edits,
98286406 Andy McCall ↶ 559 
            kind: ChangeKind::WorkingCopy,
560 
        };
561 
        let base_heads = base.maximal(&old_wc.deps);
562 
        let mut deps: BTreeSet<ChangeHash> = base_heads.into_iter().collect();
563 
        deps.extend(referenced_changes(&wc, &base));
614541c3 Andy McCall ↶ 564 
        deps.extend(built.contributors.iter().copied());
98286406 Andy McCall ↶ 565 
        wc.deps = deps.into_iter().collect();
566 
        wc.normalize();
614541c3 Andy McCall ↶ 567 
        let resolves = built.resolves;
568 
        let contributors = built.contributors;
569 
        let statuses = built.statuses;
98286406 Andy McCall ↶ 570 
        // Empty snapshot: hash the candidate before storing; only record an op on change.
8b276e01 Andy McCall ↶ 571 
        let record = crate::timing::phase("snapshot: hash and record");
17f94b13 Andy McCall ↶ 572 
        // Encoded once, its texts stored a batch at a time as they are
573 
        // made (a stored blob is not stored again); the change itself only
574 
        // when it changed.
575 
        let encoded = wc.encode_streaming(|batch| self.store.put_texts(&batch))?;
192fad1e Andy McCall ↶ 576 
        let new_hash = crate::hash::hash_object(crate::hash::ObjectType::Change, &encoded);
98286406 Andy McCall ↶ 577 
        let changed = new_hash != old_hash;
578 
        if changed {
17f94b13 Andy McCall ↶ 579 
            self.store.put(crate::hash::ObjectType::Change, &encoded)?;
98286406 Andy McCall ↶ 580 
            let mut view = op.view.clone();
581 
            view.workspaces.insert(self.workspace, new_hash);
582 
            self.record_op(&[op_ref], &format!("{command}{SNAPSHOT_SUFFIX}"), view)?;
583 
        }
8b276e01 Andy McCall ↶ 584 
        drop(record);
135212de Andy McCall ↶ 585 
        // The prompt compares against this without recording anything.
0bdc3f91 Andy McCall ↶ 586 
        let _t = crate::timing::phase("snapshot: write manifest");
992467d3 Andy McCall ↶ 587 
        let conflicted = base_snapshot.is_conflicted();
588 
        let uncommitted = !wc.tree_ops.is_empty() || !wc.edits.is_empty();
589 
        // Rewriting the manifest pays only when it would teach the next
590 
        // snapshot something: other flags, a file found equal to the base
591 
        // (it need not be read again), a new blob, a path added or gone.
592 
        // An edited file is read next time whatever it says.
593 
        let worth = match self.read_manifest()? {
f9466021 Andy McCall ↶ 594 
            _ if force_manifest => true,
992467d3 Andy McCall ↶ 595 
            None => true,
596 
            Some((c, u, m)) => {
597 
                c != conflicted
598 
                    || u != uncommitted
599 
                    || m.entries.len() != fs_entries.len()
600 
                    || fs_entries.iter().any(|(p, e)| {
601 
                        !e.unchanged && (e.graph_key.is_some() || !m.entries.contains_key(p))
602 
                    })
603 
                    || built
604 
                        .blobs
605 
                        .iter()
606 
                        .any(|(p, b)| m.entries.get(p).and_then(|e| e.blob) != Some(*b))
36041796 Andy McCall ↶ 607 
                    // With uncommitted work, the status cache below holds
608 
                    // only while the manifest describes the edited files as
609 
                    // they are now.
610 
                    || (uncommitted && statuses.iter().any(|st| {
611 
                        let Some(e) = fs_entries.get(&st.path) else {
612 
                            return m.entries.contains_key(&st.path);
613 
                        };
614 
                        let Some(me) = m.entries.get(&st.path) else {
615 
                            return true;
616 
                        };
617 
                        let hash = e
618 
                            .content_hash
619 
                            .unwrap_or_else(|| *blake3::hash(&e.content).as_bytes());
620 
                        let stat = e.stat.or_else(|| {
621 
                            fs::symlink_metadata(self.root.join(&st.path))
622 
                                .ok()
623 
                                .map(|md| (md.len(), super::prompt::mtime_ns(&md)))
624 
                        });
e226a6cc Andy McCall ↶ 625 
                        // The executable bit too: a mode change moves
626 
                        // neither size nor time.
627 
                        me.hash != hash || me.exec != e.exec || stat != Some((me.size, me.mtime_ns))
36041796 Andy McCall ↶ 628 
                    }))
992467d3 Andy McCall ↶ 629 
            }
630 
        };
631 
        if worth {
632 
            self.write_manifest_entries(conflicted, uncommitted, &fs_entries, &built.blobs)?;
633 
        }
36041796 Andy McCall ↶ 634 
        self.write_status_cache((uncommitted && !conflicted).then_some(&new_hash), &statuses);
f9466021 Andy McCall ↶ 635 
        let attributes = crate::attributes::Attributes::from_files(
636 
            fs_entries
637 
                .iter()
638 
                .filter(|(p, _)| is_attributes(p))
639 
                .map(|(p, e)| (p.as_str(), e.content.as_slice())),
640 
        );
75167672 Andy McCall 641 
        Ok(SnapshotResult {
642 
            wc_hash: new_hash,
643 
            wc,
644 
            base,
645 
            base_snapshot,
646 
            statuses,
647 
            changed,
648 
            resolves,
649 
            contributors,
f9466021 Andy McCall ↶ 650 
            attributes,
d4dbab97 Andy McCall ↶ 651 
            untracked_nested: self.untracked_nested.borrow().clone(),
75167672 Andy McCall 652 
        })
98286406 Andy McCall ↶ 653 
    }
654
50a046e4 Andy McCall ↶ 655 
    /// `oxy status --json` (spec §9.5): the changed paths and every conflict
656 
    /// of the working copy's base with its kind, path, and contributing
657 
    /// ChangeIds.
658 
    pub fn status_json(&self, snap: &SnapshotResult) -> Result<String> {
659 
        let heads = self.bookmark_heads()?;
660 
        let base_snapshot = &snap.base_snapshot;
661 
        let by_node = base_snapshot.tree.by_node();
662 
        let path_of = |n: &NodeId| by_node.get(n).map(|e| e.path.clone());
75167672 Andy McCall 663 
        let id_of = |h: &ChangeHash| {
664 
            snap.base
665 
                .get(h)
666 
                .map(|m| m.change_id.to_hex())
667 
                .unwrap_or_else(|| h.to_hex())
668 
        };
669 
        let paths = json_array(snap.statuses.iter().map(|s| {
670 
            format!(
671 
                "{{\"path\":{},\"status\":{}}}",
672 
                json_str(&s.path),
673 
                json_str(&format!("{:?}", s.status))
674 
            )
675 
        }));
50a046e4 Andy McCall ↶ 676 
        let mut conflicts: Vec<String> = Vec::new();
677 
        for (p, f) in &base_snapshot.files {
678 
            if !f.is_conflicted() {
679 
                continue;
680 
            }
681 
            let (kind, changes) = match &f.content {
75167672 Andy McCall 682 
                FileContent::Text { .. } => {
683 
                    ("text", snap.base.conflict_regions(&f.node).contributors)
684 
                }
685 
                FileContent::Opaque { blobs } => {
686 
                    ("replace", snap.base.blob_contributors(&f.node, blobs))
687 
                }
50a046e4 Andy McCall ↶ 688 
                FileContent::Dir => continue,
689 
            };
75167672 Andy McCall 690 
            let resolved = match snap
691 
                .statuses
692 
                .iter()
693 
                .find(|s| s.path == *p)
694 
                .map(|s| s.status)
695 
            {
50a046e4 Andy McCall ↶ 696 
                Some(ChangeStatus::Resolved) => "true",
697 
                Some(ChangeStatus::ConflictEdited) => "\"markers\"",
698 
                _ => "false",
699 
            };
700 
            conflicts.push(format!(
701 
                "{{\"kind\":{},\"path\":{},\"node\":{},\"changes\":{},\"resolved\":{resolved}}}",
702 
                json_str(kind),
703 
                json_str(p),
704 
                json_str(&f.node.to_hex()),
705 
                json_array(changes.iter().map(|h| json_str(&id_of(h))))
706 
            ));
707 
        }
708 
        for c in &base_snapshot.tree.conflicts {
709 
            let (kind, nodes): (&str, Vec<NodeId>) = match c {
710 
                crate::tree::TreeConflict::Name { nodes, .. } => ("name", nodes.clone()),
75167672 Andy McCall 711 
                crate::tree::TreeConflict::MultiPlacement { node, .. } => {
712 
                    ("multi-placement", vec![*node])
713 
                }
50a046e4 Andy McCall ↶ 714 
                crate::tree::TreeConflict::Orphan { node, .. } => ("orphan", vec![*node]),
715 
                crate::tree::TreeConflict::Cycle { node } => ("cycle", vec![*node]),
716 
                crate::tree::TreeConflict::Mode { node, .. } => ("mode", vec![*node]),
717 
            };
718 
            let detail = match c {
719 
                crate::tree::TreeConflict::Name { name, parent, .. } => {
75167672 Andy McCall 720 
                    let dir = if *parent == NodeId::ROOT {
721 
                        String::new()
722 
                    } else {
723 
                        path_of(parent).unwrap_or_default()
724 
                    };
725 
                    format!(
726 
                        ",\"path\":{}",
727 
                        json_str(&if dir.is_empty() {
728 
                            name.clone()
729 
                        } else {
730 
                            format!("{dir}/{name}")
731 
                        })
732 
                    )
50a046e4 Andy McCall ↶ 733 
                }
75167672 Andy McCall 734 
                _ => nodes
735 
                    .first()
736 
                    .and_then(path_of)
737 
                    .map(|p| format!(",\"path\":{}", json_str(&p)))
738 
                    .unwrap_or_default(),
50a046e4 Andy McCall ↶ 739 
            };
740 
            conflicts.push(format!(
741 
                "{{\"kind\":{},\"nodes\":{}{detail}}}",
742 
                json_str(kind),
743 
                json_array(nodes.iter().map(|n| json_str(&n.to_hex())))
744 
            ));
745 
        }
746 
        Ok(format!(
d4dbab97 Andy McCall ↶ 747 
            "{{\"bookmark\":{},\"working_copy\":{},\"heads\":{},\"clean\":{},\"conflicted\":{},\"paths\":{paths},\"conflicts\":{},\"untracked_nested\":{}}}",
50a046e4 Andy McCall ↶ 748 
            json_str(&self.config.bookmark),
749 
            json_str(&snap.wc.change_id.to_hex()),
750 
            heads.len(),
751 
            snap.statuses.is_empty(),
752 
            base_snapshot.is_conflicted(),
d4dbab97 Andy McCall ↶ 753 
            json_array(conflicts),
754 
            json_array(snap.untracked_nested.iter().map(|p| json_str(p)))
50a046e4 Andy McCall ↶ 755 
        ))
756 
    }
757
98286406 Andy McCall ↶ 758 
    /// Turn the working-copy change into a normal change on the bookmark (spec §12.3).
759 
    pub fn commit(&self, message: &str, extra_deps: &[ChangeHash]) -> Result<ChangeHash> {
957fee30 Andy McCall ↶ 760 
        self.commit_selection(message, extra_deps, &Selection::All)
761 
    }
762
763 
    /// The hunks of the working copy, for `oxy commit --interactive`: each
764 
    /// tree operation and each edit, in the order `select_hunks` numbers them.
765 
    pub fn hunks(&self) -> Result<(SnapshotResult, Vec<Hunk>)> {
8ab265dc Andy McCall ↶ 766 
        let snap = self.snapshot_status("oxy commit")?;
957fee30 Andy McCall ↶ 767 
        let hunks = render_hunks(&snap.wc, &snap.base, &snap.base_snapshot);
768 
        Ok((snap, hunks))
769 
    }
770
771 
    /// Commit part of the working copy (spec §12.3). What is not selected
772 
    /// stays on disk as uncommitted work: the next snapshot rebuilds it
773 
    /// against the new base, so the working copy always describes the
774 
    /// directory.
f9466021 Andy McCall ↶ 775 
    /// The graph key in `st` of each text file at `paths`, the paths a
776 
    /// commit changed: only their graphs changed, so the keys the manifest
777 
    /// holds for the others still stand (and any that does not is simply
778 
    /// not trusted by the next snapshot, which compares keys). Files with
779 
    /// an `eol` attribute are left out: their bytes on disk are not the
780 
    /// rendering.
781 
    fn committed_graph_keys(
782 
        &self,
783 
        st: &State,
784 
        paths: &[String],
785 
        attrs: &crate::attributes::Attributes,
786 
    ) -> HashMap<String, [u8; 32]> {
86e1824f Andy McCall ↶ 787 
        let _t = crate::timing::phase("commit: graph keys");
f9466021 Andy McCall ↶ 788 
        let view = st.tree().view();
789 
        paths
86e1824f Andy McCall ↶ 790 
            .iter()
f9466021 Andy McCall ↶ 791 
            .filter_map(|p| {
792 
                let e = view.entries.get(p)?;
793 
                (e.kind == NodeKind::File && !e.mode.opaque && attrs.lookup(p).eol.is_none())
794 
                    .then_some(())?;
795 
                Some((p.clone(), st.graph_key(&e.node)?))
86e1824f Andy McCall ↶ 796 
            })
8457a6cc Andy McCall ↶ 797 
            .collect()
86e1824f Andy McCall ↶ 798 
    }
799
75167672 Andy McCall 800 
    pub fn commit_selection(
801 
        &self,
802 
        message: &str,
803 
        extra_deps: &[ChangeHash],
804 
        selection: &Selection,
805 
    ) -> Result<ChangeHash> {
6caacfff Andy McCall ↶ 806 
        let _wc = self.lock_working_copy()?;
e226a6cc Andy McCall ↶ 807 
        let mut snap = match self.snapshot_from_cache()? {
808 
            Some(snap) => snap,
809 
            None => self.snapshot_as("oxy commit", true, true)?,
810 
        };
98286406 Andy McCall ↶ 811 
        if snap.wc.tree_ops.is_empty() && snap.wc.edits.is_empty() {
812 
            return fail("nothing to commit: the working copy matches its base");
813 
        }
75167672 Andy McCall 814 
        if let Some(s) = snap
815 
            .statuses
816 
            .iter()
817 
            .find(|s| s.status == ChangeStatus::ConflictEdited)
818 
        {
98286406 Andy McCall ↶ 819 
            return fail(format!("{} still contains conflict markers", s.path));
820 
        }
821 
        if message.trim().is_empty() {
822 
            return fail("a commit message is required");
823 
        }
192fad1e Andy McCall ↶ 824 
        // What the whole working copy references, before a whole commit
825 
        // takes its operations over (they are moved, not copied: for a
826 
        // large tree they are most of the memory).
827 
        let wc_refs = referenced_changes(&snap.wc, &snap.base);
f9466021 Andy McCall ↶ 828 
        let changed_paths: Vec<String> = snap.statuses.iter().map(|s| s.path.clone()).collect();
957fee30 Andy McCall ↶ 829 
        let (tree_ops, edits, partial) = match selection {
192fad1e Andy McCall ↶ 830 
            Selection::All => (
831 
                std::mem::take(&mut snap.wc.tree_ops),
832 
                std::mem::take(&mut snap.wc.edits),
833 
                false,
834 
            ),
957fee30 Andy McCall ↶ 835 
            Selection::Paths(paths) => {
836 
                let (o, e) = select_paths(&snap.wc, &snap.base_snapshot, paths);
837 
                let partial = o.len() != snap.wc.tree_ops.len() || e.len() != snap.wc.edits.len();
838 
                (o, e, partial)
839 
            }
840 
            Selection::Hunks(indices) => {
841 
                let (o, e) = select_hunks(&snap.wc, indices);
842 
                let partial = o.len() != snap.wc.tree_ops.len() || e.len() != snap.wc.edits.len();
843 
                (o, e, partial)
844 
            }
845 
        };
846 
        if tree_ops.is_empty() && edits.is_empty() {
847 
            return fail("nothing selected to commit");
848 
        }
849 
        if partial && snap.resolves {
850 
            return fail("a conflict resolution must be committed whole");
851 
        }
6d3eefbc Andy McCall ↶ 852 
        // pre-commit hook: may veto.
853 
        self.run_hook(
854 
            "pre-commit",
855 
            &format!(
856 
                "{{\"event\":\"pre-commit\",\"message\":{},\"paths\":{}}}",
857 
                json_str(message),
75167672 Andy McCall 858 
                json_array(snap.statuses.iter().map(|s| format!(
859 
                    "{{\"path\":{},\"status\":{}}}",
860 
                    json_str(&s.path),
861 
                    json_str(&format!("{:?}", s.status))
862 
                )))
6d3eefbc Andy McCall ↶ 863 
            ),
864 
        )?;
98286406 Andy McCall ↶ 865 
        let (op_ref, op) = self.head_op()?;
192fad1e Andy McCall ↶ 866 
        let mut deps: BTreeSet<ChangeHash> = wc_refs;
6d3eefbc Andy McCall ↶ 867 
        // semantic-deps hook: may add explicit dependencies (spec §8.1).
868 
        if self.config.semantic_deps {
869 
            let touched: Vec<String> = snap.statuses.iter().map(|s| s.path.clone()).collect();
870 
            let by_node = snap.base_snapshot.tree.by_node();
871 
            let mut candidates: Vec<(ChangeId, ChangeHash, Vec<String>)> = Vec::new();
872 
            let mut seen: BTreeSet<ChangeHash> = BTreeSet::new();
873 
            for h in deps.iter().chain(snap.base.maximal(&snap.wc.deps).iter()) {
874 
                if !seen.insert(*h) {
875 
                    continue;
876 
                }
877 
                let c = self.store.get_change(h)?;
878 
                let mut paths: BTreeSet<String> = BTreeSet::new();
75167672 Andy McCall 879 
                for n in c
880 
                    .tree_ops
881 
                    .iter()
882 
                    .map(|o| o.node())
883 
                    .chain(c.edits.iter().map(|e| e.node()))
884 
                {
6d3eefbc Andy McCall ↶ 885 
                    if let Some(e) = by_node.get(&n) {
886 
                        paths.insert(e.path.clone());
887 
                    }
888 
                }
889 
                candidates.push((c.change_id, *h, paths.into_iter().collect()));
890 
            }
891 
            for d in self.semantic_deps(&snap.wc.change_id, &touched, &candidates)? {
892 
                if snap.base.contains(&d) {
893 
                    deps.insert(d);
894 
                }
895 
            }
896 
        }
98286406 Andy McCall ↶ 897 
        // A resolution depends on every change that contributed to the
898 
        // conflict (spec §8.1). Tree and opaque conflicts are resolved through
899 
        // ordinary operations whose references already cover the contributors.
900 
        deps.extend(snap.contributors.iter().copied());
901 
        for d in extra_deps {
902 
            if !snap.base.contains(d) {
75167672 Andy McCall 903 
                return fail(format!(
904 
                    "--depends-on {d}: not in the working copy's base state"
905 
                ));
98286406 Andy McCall ↶ 906 
            }
907 
            deps.insert(*d);
908 
        }
909 
        let mut change = Change {
6f8aeb99 Andy McCall ↶ 910 
            version: crate::objects::CHANGE_VERSION,
75167672 Andy McCall 911 
            change_id: if partial {
912 
                ChangeId::random()
913 
            } else {
914 
                snap.wc.change_id
915 
            },
957fee30 Andy McCall ↶ 916 
            deps: vec![],
98286406 Andy McCall ↶ 917 
            author: self.author(),
918 
            hlc: Hlc::now(),
919 
            message: message.trim_end().to_string(),
957fee30 Andy McCall ↶ 920 
            tree_ops,
921 
            edits,
75167672 Andy McCall 922 
            kind: if snap.resolves {
923 
                ChangeKind::Resolution
924 
            } else {
925 
                ChangeKind::Normal
926 
            },
98286406 Andy McCall ↶ 927 
        };
957fee30 Andy McCall ↶ 928 
        if partial {
929 
            // Dependencies come from what the selected part references, not
930 
            // from the whole working copy.
931 
            deps = referenced_changes(&change, &snap.base);
932 
            for d in extra_deps {
933 
                deps.insert(*d);
934 
            }
935 
        }
936 
        change.deps = deps.into_iter().collect();
98286406 Andy McCall ↶ 937 
        change.normalize();
f9466021 Andy McCall ↶ 938 
        let signing = crate::timing::phase("commit: sign and store");
614541c3 Andy McCall ↶ 939 
        let hash = self.store_signed(&change)?;
f9466021 Andy McCall ↶ 940 
        drop(signing);
941 
        let extending = crate::timing::phase("commit: extend the state");
98286406 Andy McCall ↶ 942
943 
        // New bookmark heads: maximal elements of old heads plus the new change.
944 
        // The working copy continues on its own base plus the new change, which
945 
        // is exactly what the files on disk contain; the bookmark may hold
946 
        // other heads (and conflicts) the working copy has not checked out.
947 
        let old_heads = self.heads_of(&op.view, &self.config.bookmark)?;
948 
        let old_base = snap.base.maximal(&snap.wc.deps);
949 
        let mut all: Vec<ChangeHash> = old_heads.clone();
950 
        all.extend(old_base.iter().copied());
951 
        all.push(hash);
07eb99be Andy McCall ↶ 952 
        // The snapshot already loaded the working copy's base; when that also
953 
        // holds every bookmark head, it is the state to extend.
954 
        let mut st = if old_heads.iter().all(|h| snap.base.contains(h)) {
955 
            snap.base
956 
        } else {
957 
            self.load_state(&all)?
958 
        };
192fad1e Andy McCall ↶ 959 
        st.add_hashed(hash, change)?;
98286406 Andy McCall ↶ 960 
        let mut with_new = old_heads.clone();
961 
        with_new.push(hash);
962 
        let new_heads = st.maximal(&with_new);
252e8cb2 Andy McCall ↶ 963 
        // Automatic checkpoint once enough changes accumulated (spec §11).
75167672 Andy McCall 964 
        let since = self
965 
            .latest_checkpoint(&self.config.bookmark)?
966 
            .map(|(_, cp)| cp.count)
967 
            .unwrap_or(0);
968 
        if self.config.checkpoint_interval > 0
969 
            && (st.len() as u64).saturating_sub(since) >= self.config.checkpoint_interval
970 
        {
252e8cb2 Andy McCall ↶ 971 
            let cp_state = self.load_state_full(&new_heads)?;
972 
            self.write_checkpoint(&self.config.bookmark, &cp_state, &new_heads)?;
973 
        }
98286406 Andy McCall ↶ 974 
        let mut wc_base = old_base.clone();
975 
        wc_base.push(hash);
976 
        let wc_base = st.maximal(&wc_base);
f9466021 Andy McCall ↶ 977 
        drop(extending);
98286406 Andy McCall ↶ 978
8457a6cc Andy McCall ↶ 979 
        // The graph keys of the files as they now are, from the state the
980 
        // commit just extended: a file whose graph it built has none, and
981 
        // is read by the next snapshot; a key the next base does not share
982 
        // (the bookmark held other heads) is simply not trusted then.
f9466021 Andy McCall ↶ 983 
        let committed_keys =
984 
            (!partial).then(|| self.committed_graph_keys(&st, &changed_paths, &snap.attributes));
985 
        let recording = crate::timing::phase("commit: record");
98286406 Andy McCall ↶ 986 
        let wc = self.new_working_copy(wc_base, "");
987 
        let wc_hash = self.store.put_change(&wc)?;
988 
        let mut view = op.view.clone();
75167672 Andy McCall 989 
        view.bookmarks.insert(
990 
            self.config.bookmark.clone(),
991 
            self.store.put_state(&StateObject::new(new_heads))?,
992 
        );
98286406 Andy McCall ↶ 993 
        view.workspaces.insert(self.workspace, wc_hash);
994 
        self.record_op(&[op_ref], &format!("oxy commit -m {message:?}"), view)?;
f9466021 Andy McCall ↶ 995 
        drop(recording);
996 
        let _rewrite = crate::timing::phase("commit: manifest and hooks");
957fee30 Andy McCall ↶ 997 
        if partial {
998 
            // The rest is rebuilt from disk by the next snapshot.
999 
            self.drop_manifest();
1000 
        } else {
86e1824f Andy McCall ↶ 1001 
            let conflicted = snap.base_snapshot.is_conflicted() && !snap.resolves;
1002 
            // The files on disk are now exactly the new base's renderings:
1003 
            // record their graph keys, so the next snapshot neither reads nor
1004 
            // renders them (oxygen#35).
1005 
            let keys = if conflicted {
1006 
                HashMap::new()
1007 
            } else {
8457a6cc Andy McCall ↶ 1008 
                committed_keys.unwrap_or_default()
86e1824f Andy McCall ↶ 1009 
            };
1010 
            self.rewrite_manifest(conflicted, false, &keys)?;
957fee30 Andy McCall ↶ 1011 
        }
d02e545d Andy McCall ↶ 1012 
        self.maybe_autopack()?;
75167672 Andy McCall 1013 
        let _ = self.run_hook(
1014 
            "post-commit",
1015 
            &format!(
1016 
                "{{\"event\":\"post-commit\",\"change_id\":{},\"hash\":{},\"message\":{}}}",
1017 
                json_str(&snap.wc.change_id.to_hex()),
1018 
                json_str(&hash.to_hex()),
1019 
                json_str(message)
1020 
            ),
1021 
        );
98286406 Andy McCall ↶ 1022 
        Ok(hash)
1023 
    }
1024 
}
1025
957fee30 Andy McCall ↶ 1026 
/// What part of the working copy a commit takes (spec §12.3).
1027 
#[derive(Clone, Debug)]
1028 
pub enum Selection {
1029 
    All,
1030 
    /// Every operation and edit on nodes under these paths.
1031 
    Paths(Vec<String>),
1032 
    /// Hunk indices as `Repo::hunks` numbers them; dependent hunks are added.
1033 
    Hunks(Vec<usize>),
1034 
}
1035
1036 
/// One selectable piece of the working copy: a tree operation or an edit.
1037 
#[derive(Clone, Debug)]
1038 
pub struct Hunk {
1039 
    pub index: usize,
1040 
    pub path: String,
1041 
    /// Rendered like `oxy diff`.
1042 
    pub text: String,
1043 
}
1044
1045 
/// The tree operations and edits on nodes under `paths`, plus the
1046 
/// additions of any new parent directories they need.
75167672 Andy McCall 1047 
fn select_paths(
1048 
    wc: &Change,
1049 
    base_snapshot: &Snapshot,
1050 
    paths: &[String],
1051 
) -> (Vec<TreeOp>, Vec<Edit>) {
1052 
    let selected = |p: &str| {
1053 
        paths
1054 
            .iter()
1055 
            .any(|x| p == x || p.starts_with(&format!("{}/", x.trim_end_matches('/'))))
1056 
    };
957fee30 Andy McCall ↶ 1057 
    let by_node = base_snapshot.tree.by_node();
1058 
    let mut new_names: HashMap<NodeId, (NodeId, String, NodeKind)> = HashMap::new();
1059 
    for op in &wc.tree_ops {
75167672 Andy McCall 1060 
        if let TreeOp::AddNode {
1061 
            node,
1062 
            parent,
1063 
            name,
1064 
            kind,
1065 
            ..
1066 
        } = op
1067 
        {
957fee30 Andy McCall ↶ 1068 
            new_names.insert(*node, (*parent, name.clone(), *kind));
1069 
        }
1070 
    }
1071 
    let mut nodes: BTreeSet<NodeId> = BTreeSet::new();
75167672 Andy McCall 1072 
    for n in wc
1073 
        .tree_ops
1074 
        .iter()
1075 
        .map(|o| o.node())
1076 
        .chain(wc.edits.iter().map(|e| e.node()))
1077 
    {
957fee30 Andy McCall ↶ 1078 
        if path_of_node(&n, &by_node, &new_names).is_some_and(|p| selected(&p)) {
1079 
            nodes.insert(n);
1080 
        }
1081 
    }
1082 
    // New parents of selected new nodes come along.
1083 
    let mut changed = true;
1084 
    while changed {
1085 
        changed = false;
1086 
        for (n, (parent, _, _)) in &new_names {
1087 
            if nodes.contains(n) && new_names.contains_key(parent) && nodes.insert(*parent) {
1088 
                changed = true;
1089 
            }
1090 
        }
1091 
    }
75167672 Andy McCall 1092 
    let ops = wc
1093 
        .tree_ops
1094 
        .iter()
1095 
        .filter(|o| nodes.contains(&o.node()))
1096 
        .cloned()
1097 
        .collect();
1098 
    let edits = wc
1099 
        .edits
1100 
        .iter()
1101 
        .filter(|e| nodes.contains(&e.node()))
1102 
        .cloned()
1103 
        .collect();
957fee30 Andy McCall ↶ 1104 
    (ops, edits)
1105 
}
1106
1107 
/// The hunks `indices` name plus whatever they refer to within the working
1108 
/// copy (the parent directory of an added node, the insert that introduced
1109 
/// an anchor line), renumbered so the result is a well-formed change.
1110 
fn select_hunks(wc: &Change, indices: &[usize]) -> (Vec<TreeOp>, Vec<Edit>) {
1111 
    let n_ops = wc.tree_ops.len();
1112 
    let mut ops_sel = vec![false; n_ops];
1113 
    let mut edits_sel = vec![false; wc.edits.len()];
1114 
    for &i in indices {
1115 
        if i < n_ops {
1116 
            ops_sel[i] = true;
1117 
        } else if i - n_ops < wc.edits.len() {
1118 
            edits_sel[i - n_ops] = true;
1119 
        }
1120 
    }
1121 
    // Atom ranges each insert introduces, per node, in the working copy's numbering.
1122 
    let mut per_node: HashMap<NodeId, u32> = HashMap::new();
1123 
    let mut insert_ranges: Vec<Option<(NodeId, u32, u32)>> = Vec::new();
1124 
    for e in &wc.edits {
1125 
        insert_ranges.push(match e {
1126 
            Edit::Insert { node, lines, .. } => {
1127 
                let start = per_node.entry(*node).or_default();
1128 
                let r = (*node, *start, *start + lines.len() as u32);
1129 
                *start += lines.len() as u32;
1130 
                Some(r)
1131 
            }
1132 
            _ => None,
1133 
        });
1134 
    }
75167672 Andy McCall 1135 
    let add_index: HashMap<NodeId, usize> = wc
1136 
        .tree_ops
1137 
        .iter()
1138 
        .enumerate()
1139 
        .filter_map(|(i, o)| {
1140 
            if let TreeOp::AddNode { node, .. } = o {
1141 
                Some((*node, i))
1142 
            } else {
1143 
                None
1144 
            }
1145 
        })
1146 
        .collect();
1147 
    let insert_for = |node: &NodeId, index: u32| -> Option<usize> {
1148 
        insert_ranges
1149 
            .iter()
1150 
            .position(|r| matches!(r, Some((n, a, b)) if n == node && *a <= index && index < *b))
1151 
    };
957fee30 Andy McCall ↶ 1152 
    // Closure.
1153 
    let mut changed = true;
1154 
    while changed {
1155 
        changed = false;
1156 
        for i in 0..n_ops {
1157 
            if !ops_sel[i] {
1158 
                continue;
1159 
            }
d8c086ca Andy McCall ↶ 1160 
            if let TreeOp::AddNode { node, parent, .. } = &wc.tree_ops[i] {
957fee30 Andy McCall ↶ 1161 
                if let Some(&p) = add_index.get(parent) {
1162 
                    if !ops_sel[p] {
1163 
                        ops_sel[p] = true;
1164 
                        changed = true;
1165 
                    }
1166 
                }
d8c086ca Andy McCall ↶ 1167 
                // A new node's content belongs with its addition: nobody
1168 
                // wants an empty file committed apart from its lines.
1169 
                for (j, e) in wc.edits.iter().enumerate() {
1170 
                    if e.node() == *node && !edits_sel[j] {
1171 
                        edits_sel[j] = true;
1172 
                        changed = true;
1173 
                    }
1174 
                }
957fee30 Andy McCall ↶ 1175 
            }
1176 
        }
1177 
        for j in 0..wc.edits.len() {
1178 
            if !edits_sel[j] {
1179 
                continue;
1180 
            }
1181 
            let e = &wc.edits[j];
1182 
            if let Some(&a) = add_index.get(&e.node()) {
1183 
                if !ops_sel[a] {
1184 
                    ops_sel[a] = true;
1185 
                    changed = true;
1186 
                }
1187 
            }
75167672 Andy McCall 1188 
            if let Edit::Insert {
1189 
                node,
1190 
                after,
1191 
                before,
1192 
                ..
1193 
            } = e
1194 
            {
957fee30 Andy McCall ↶ 1195 
                for r in [after, before] {
1196 
                    if let AtomRef::Atom { change, index } = r {
1197 
                        if change.is_zero() {
1198 
                            if let Some(k) = insert_for(node, *index) {
1199 
                                if !edits_sel[k] {
1200 
                                    edits_sel[k] = true;
1201 
                                    changed = true;
1202 
                                }
1203 
                            }
1204 
                        }
1205 
                    }
1206 
                }
1207 
            }
1208 
        }
1209 
    }
1210 
    // Renumber self-references: old atom index → new index among selected inserts.
1211 
    let mut remap: HashMap<(NodeId, u32), u32> = HashMap::new();
1212 
    let mut new_counts: HashMap<NodeId, u32> = HashMap::new();
1213 
    for (j, r) in insert_ranges.iter().enumerate() {
1214 
        if let (true, Some((node, a, b))) = (edits_sel[j], r) {
1215 
            let next = new_counts.entry(*node).or_default();
1216 
            for old in *a..*b {
1217 
                remap.insert((*node, old), *next);
1218 
                *next += 1;
1219 
            }
1220 
        }
1221 
    }
1222 
    let map_ref = |r: AtomRef, node: &NodeId| -> AtomRef {
1223 
        match r {
75167672 Andy McCall 1224 
            AtomRef::Atom { change, index } if change.is_zero() => AtomRef::Atom {
1225 
                change,
1226 
                index: remap.get(&(*node, index)).copied().unwrap_or(index),
1227 
            },
957fee30 Andy McCall ↶ 1228 
            other => other,
1229 
        }
1230 
    };
75167672 Andy McCall 1231 
    let ops = wc
1232 
        .tree_ops
1233 
        .iter()
1234 
        .enumerate()
1235 
        .filter(|(i, _)| ops_sel[*i])
1236 
        .map(|(_, o)| o.clone())
1237 
        .collect();
957fee30 Andy McCall ↶ 1238 
    let edits = wc
1239 
        .edits
1240 
        .iter()
1241 
        .enumerate()
1242 
        .filter(|(j, _)| edits_sel[*j])
1243 
        .map(|(_, e)| match e {
75167672 Andy McCall 1244 
            Edit::Insert {
1245 
                node,
1246 
                after,
1247 
                before,
1248 
                lines,
1249 
            } => Edit::Insert {
1250 
                node: *node,
1251 
                after: map_ref(*after, node),
1252 
                before: map_ref(*before, node),
1253 
                lines: lines.clone(),
1254 
            },
957fee30 Andy McCall ↶ 1255 
            other => other.clone(),
1256 
        })
1257 
        .collect();
1258 
    (ops, edits)
1259 
}
1260
1261 
/// Render each tree operation and edit of `change` on its own, numbered.
1262 
pub fn render_hunks(change: &Change, base: &State, base_snapshot: &Snapshot) -> Vec<Hunk> {
1263 
    let by_node = base_snapshot.tree.by_node();
1264 
    let mut new_names: HashMap<NodeId, (NodeId, String, NodeKind)> = HashMap::new();
1265 
    for op in &change.tree_ops {
75167672 Andy McCall 1266 
        if let TreeOp::AddNode {
1267 
            node,
1268 
            parent,
1269 
            name,
1270 
            kind,
1271 
            ..
1272 
        } = op
1273 
        {
957fee30 Andy McCall ↶ 1274 
            new_names.insert(*node, (*parent, name.clone(), *kind));
1275 
        }
1276 
    }
1277 
    let mut out = Vec::new();
1278 
    for (i, op) in change.tree_ops.iter().enumerate() {
75167672 Andy McCall 1279 
        let one = Change {
1280 
            tree_ops: vec![op.clone()],
1281 
            edits: vec![],
1282 
            ..change.clone()
1283 
        };
957fee30 Andy McCall ↶ 1284 
        let path = path_of_node(&op.node(), &by_node, &new_names).unwrap_or_default();
75167672 Andy McCall 1285 
        out.push(Hunk {
1286 
            index: i,
1287 
            path,
1288 
            text: render_change(&one, base, base_snapshot),
1289 
        });
957fee30 Andy McCall ↶ 1290 
    }
1291 
    for (j, e) in change.edits.iter().enumerate() {
75167672 Andy McCall 1292 
        let one = Change {
1293 
            tree_ops: vec![],
1294 
            edits: vec![e.clone()],
1295 
            ..change.clone()
1296 
        };
957fee30 Andy McCall ↶ 1297 
        let path = path_of_node(&e.node(), &by_node, &new_names).unwrap_or_default();
75167672 Andy McCall 1298 
        out.push(Hunk {
1299 
            index: change.tree_ops.len() + j,
1300 
            path,
1301 
            text: render_change(&one, base, base_snapshot),
1302 
        });
957fee30 Andy McCall ↶ 1303 
    }
1304 
    out
1305 
}
1306
c6aa5bd9 Andy McCall ↶ 1307 
/// One file's part of a diff, for `oxy diff --json`.
1308 
#[derive(Clone, Debug)]
1309 
pub struct FileDiff {
1310 
    pub path: String,
1311 
    /// `added`, `removed`, `modified`, `renamed`, `mode`, `replaced`.
1312 
    pub kind: String,
1313 
    pub hunks: Vec<DiffHunk>,
1314 
    /// For renames, the previous path.
1315 
    pub from: Option<String>,
1316 
}
1317
1318 
/// Lines inserted after `base_line` (0 = before the first line) and lines
1319 
/// removed, with their base line numbers.
1320 
#[derive(Clone, Debug, Default)]
1321 
pub struct DiffHunk {
1322 
    pub base_line: u32,
1323 
    pub added: Vec<Vec<u8>>,
1324 
    pub removed: Vec<(u32, Vec<u8>)>,
1325 
}
1326
1327 
impl Repo {
1328 
    /// The content of `path` in a state: `heads`, or the working copy's base.
1329 
    pub fn file_at(&self, path: &str, heads: Option<&[ChangeHash]>) -> Result<Vec<u8>> {
1330 
        let snapshot = match heads {
1331 
            Some(h) => self.load_state(h)?.materialize(),
1332 
            None => {
1333 
                let (_, wc) = self.working_copy()?;
1334 
                self.load_state(&wc.deps)?.materialize()
1335 
            }
1336 
        };
75167672 Andy McCall 1337 
        let Some(f) = snapshot.files.get(path) else {
1338 
            return fail(format!("{path} is not in that state"));
1339 
        };
c6aa5bd9 Andy McCall ↶ 1340 
        match &f.content {
1341 
            FileContent::Dir => fail(format!("{path} is a directory")),
1342 
            FileContent::Text { bytes, .. } => Ok(bytes.clone()),
1343 
            FileContent::Opaque { blobs } => match blobs.first() {
1344 
                Some(b) => self.read_blob(b),
1345 
                None => Ok(vec![]),
1346 
            },
1347 
        }
1348 
    }
1349
1350 
    /// Restore `paths` (files or directories) to the working copy's base:
1351 
    /// edits are undone, additions removed, removals put back. Returns the
1352 
    /// number of paths touched.
1353 
    pub fn discard(&self, paths: &[String]) -> Result<usize> {
6caacfff Andy McCall ↶ 1354 
        let _wc = self.lock_working_copy()?;
8ab265dc Andy McCall ↶ 1355 
        let snap = self.snapshot_status("oxy discard")?;
75167672 Andy McCall 1356 
        let under = |p: &str| {
1357 
            paths
1358 
                .iter()
1359 
                .any(|x| p == x || p.starts_with(&format!("{}/", x.trim_end_matches('/'))))
1360 
        };
c6aa5bd9 Andy McCall ↶ 1361 
        let attrs = Repo::state_attributes(&snap.base_snapshot);
1362 
        let mut n = 0;
1363 
        for s in &snap.statuses {
1364 
            if !under(&s.path) {
1365 
                continue;
1366 
            }
1367 
            match snap.base_snapshot.files.get(&s.path) {
1368 
                None => {
1369 
                    // Added (or the new name of a rename): remove it.
1370 
                    let full = self.root.join(&s.path);
1371 
                    if full.is_dir() {
1372 
                        let _ = fs::remove_dir_all(&full);
1373 
                    } else {
1374 
                        let _ = fs::remove_file(&full);
1375 
                    }
1376 
                    n += 1;
1377 
                }
1378 
                Some(f) => {
1379 
                    match &f.content {
1380 
                        FileContent::Dir => fs::create_dir_all(self.root.join(&s.path))?,
1381 
                        FileContent::Text { bytes, .. } => {
75167672 Andy McCall 1382 
                            let on_disk: std::borrow::Cow<[u8]> = if attrs.lookup(&s.path).eol
1383 
                                == Some(crate::attributes::Eol::Crlf)
1384 
                            {
1385 
                                crate::attributes::to_crlf(bytes).into()
1386 
                            } else {
1387 
                                bytes.as_slice().into()
1388 
                            };
c6aa5bd9 Andy McCall ↶ 1389 
                            self.write_file(&s.path, &on_disk, f.mode.exec)?;
1390 
                        }
1391 
                        FileContent::Opaque { blobs } => {
1392 
                            let bytes = match blobs.first() {
1393 
                                Some(b) => self.read_blob(b)?,
1394 
                                None => vec![],
1395 
                            };
1396 
                            if f.kind == NodeKind::Symlink {
1397 
                                self.write_symlink(&s.path, &bytes)?;
1398 
                            } else if f.kind == NodeKind::File {
1399 
                                self.write_file(&s.path, &bytes, f.mode.exec)?;
1400 
                            }
1401 
                        }
1402 
                    }
1403 
                    n += 1;
1404 
                }
1405 
            }
1406 
        }
1407 
        // A rename's old name is not in the statuses; put it back too.
1408 
        for (p, f) in &snap.base_snapshot.files {
75167672 Andy McCall 1409 
            if under(p)
1410 
                && !self.root.join(p).exists()
1411 
                && f.kind != NodeKind::Dir
1412 
                && f.kind != NodeKind::Subrepo
1413 
                && !snap.statuses.iter().any(|s| s.path == *p)
1414 
            {
c6aa5bd9 Andy McCall ↶ 1415 
                let bytes = match &f.content {
1416 
                    FileContent::Text { bytes, .. } => bytes.clone(),
75167672 Andy McCall 1417 
                    FileContent::Opaque { blobs } => blobs
1418 
                        .first()
1419 
                        .map(|b| self.read_blob(b))
1420 
                        .transpose()?
1421 
                        .unwrap_or_default(),
c6aa5bd9 Andy McCall ↶ 1422 
                    FileContent::Dir => continue,
1423 
                };
75167672 Andy McCall 1424 
                if f.kind == NodeKind::Symlink {
1425 
                    self.write_symlink(p, &bytes)?
1426 
                } else {
1427 
                    self.write_file(p, &bytes, f.mode.exec)?
1428 
                }
c6aa5bd9 Andy McCall ↶ 1429 
                n += 1;
1430 
            }
1431 
        }
1432 
        self.drop_manifest();
1433 
        Ok(n)
1434 
    }
1435
1436 
    /// Undo the working-copy hunks `indices` (as `hunks` numbers them) on
1437 
    /// disk, keeping the others: the files are rewritten from the base plus
1438 
    /// the remaining hunks.
1439 
    pub fn discard_hunks(&self, indices: &[usize]) -> Result<usize> {
6caacfff Andy McCall ↶ 1440 
        let _wc = self.lock_working_copy()?;
c6aa5bd9 Andy McCall ↶ 1441 
        let (snap, hunks) = self.hunks()?;
75167672 Andy McCall 1442 
        let keep: Vec<usize> = hunks
1443 
            .iter()
1444 
            .map(|h| h.index)
1445 
            .filter(|i| !indices.contains(i))
1446 
            .collect();
c6aa5bd9 Andy McCall ↶ 1447 
        let (ops, edits) = select_hunks(&snap.wc, &keep);
1448 
        let dropped_nodes: BTreeSet<NodeId> = hunks
1449 
            .iter()
1450 
            .filter(|h| indices.contains(&h.index))
75167672 Andy McCall 1451 
            .map(|h| {
1452 
                if h.index < snap.wc.tree_ops.len() {
1453 
                    snap.wc.tree_ops[h.index].node()
1454 
                } else {
1455 
                    snap.wc.edits[h.index - snap.wc.tree_ops.len()].node()
1456 
                }
1457 
            })
c6aa5bd9 Andy McCall ↶ 1458 
            .collect();
1459 
        let mut partial = snap.wc.clone();
1460 
        partial.tree_ops = ops;
1461 
        partial.edits = edits;
1462 
        partial.normalize();
1463 
        let mut st = snap.base.clone();
1464 
        st.add_unchecked(partial);
8ab265dc Andy McCall ↶ 1465 
        // Every file of the target is rendered: build the graphs the
1466 
        // partial snapshot left out.
1467 
        self.load_all_graphs(&mut st)?;
c6aa5bd9 Andy McCall ↶ 1468 
        let target = st.materialize();
1469 
        let by_node_target = target.tree.by_node();
1470 
        let by_node_base = snap.base_snapshot.tree.by_node();
1471 
        let attrs = Repo::state_attributes(&target);
1472 
        let mut n = 0;
1473 
        for node in dropped_nodes {
1474 
            match by_node_target.get(&node) {
1475 
                Some(e) => {
1476 
                    let f = &target.files[&e.path];
1477 
                    match &f.content {
1478 
                        FileContent::Dir => {}
1479 
                        FileContent::Text { bytes, .. } => {
75167672 Andy McCall 1480 
                            let on_disk: std::borrow::Cow<[u8]> = if attrs.lookup(&e.path).eol
1481 
                                == Some(crate::attributes::Eol::Crlf)
1482 
                            {
1483 
                                crate::attributes::to_crlf(bytes).into()
1484 
                            } else {
1485 
                                bytes.as_slice().into()
1486 
                            };
c6aa5bd9 Andy McCall ↶ 1487 
                            self.write_file(&e.path, &on_disk, f.mode.exec)?;
1488 
                        }
1489 
                        FileContent::Opaque { blobs } => {
75167672 Andy McCall 1490 
                            let bytes = blobs
1491 
                                .first()
1492 
                                .map(|b| self.read_blob(b))
1493 
                                .transpose()?
1494 
                                .unwrap_or_default();
1495 
                            if f.kind == NodeKind::Symlink {
1496 
                                self.write_symlink(&e.path, &bytes)?
1497 
                            } else {
1498 
                                self.write_file(&e.path, &bytes, f.mode.exec)?
1499 
                            }
c6aa5bd9 Andy McCall ↶ 1500 
                        }
1501 
                    }
1502 
                    // A discarded rename: the new name goes.
75167672 Andy McCall 1503 
                    if let Some(old_path) = snap
1504 
                        .statuses
1505 
                        .iter()
1506 
                        .find(|s| {
1507 
                            s.status == ChangeStatus::Renamed && !target.files.contains_key(&s.path)
1508 
                        })
1509 
                        .map(|s| s.path.clone())
1510 
                    {
c6aa5bd9 Andy McCall ↶ 1511 
                        let _ = fs::remove_file(self.root.join(old_path));
1512 
                    }
1513 
                    n += 1;
1514 
                }
1515 
                None => {
1516 
                    // The node exists in neither target nor base with a live path: an addition to remove.
75167672 Andy McCall 1517 
                    if let Some(added) = snap.statuses.iter().find(|s| {
1518 
                        s.status == ChangeStatus::Added
1519 
                            && !target.files.contains_key(&s.path)
1520 
                            && !by_node_base.contains_key(&node)
1521 
                    }) {
c6aa5bd9 Andy McCall ↶ 1522 
                        let full = self.root.join(&added.path);
75167672 Andy McCall 1523 
                        if full.is_dir() {
1524 
                            let _ = fs::remove_dir_all(&full);
1525 
                        } else {
1526 
                            let _ = fs::remove_file(&full);
1527 
                        }
c6aa5bd9 Andy McCall ↶ 1528 
                        n += 1;
1529 
                    }
1530 
                }
1531 
            }
1532 
        }
1533 
        self.drop_manifest();
1534 
        Ok(n)
1535 
    }
1536
1537 
    /// The diff of the working copy (`None`) or of a change, per file with
1538 
    /// line-numbered hunks (spec: `oxy diff --json`).
1539 
    pub fn diff_files(&self, change: Option<&ChangeHash>) -> Result<Vec<FileDiff>> {
8ab265dc Andy McCall ↶ 1540 
        let (c, base, base_snapshot) = match change {
c6aa5bd9 Andy McCall ↶ 1541 
            Some(h) => {
1542 
                let c = self.store.get_change(h)?;
8ab265dc Andy McCall ↶ 1543 
                let (base, snapshot) = self.change_base(&c)?;
1544 
                (c, base, snapshot)
c6aa5bd9 Andy McCall ↶ 1545 
            }
77445673 Andy McCall ↶ 1546 
            None => self.working_copy_with_base()?,
c6aa5bd9 Andy McCall ↶ 1547 
        };
1548 
        Ok(diff_files_of(&c, &base, &base_snapshot))
e226a6cc Andy McCall ↶ 1549 
    }
1550
1551 
    /// The snapshot a command would take, without taking it, when the
1552 
    /// status cache holds: every file is as the last snapshot left it, so
1553 
    /// that snapshot's working-copy change is the answer. Its base comes
1554 
    /// from the state index, the `.oxyattributes` files from disk. `None`
1555 
    /// when a snapshot must be taken, and when there is nothing to commit
1556 
    /// (the snapshot then says so). A conflicted base never gets here: the
1557 
    /// cache does not hold for one.
1558 
    pub(crate) fn snapshot_from_cache(&self) -> Result<Option<SnapshotResult>> {
1559 
        let Some(statuses) = self.status_by_manifest()? else {
1560 
            return Ok(None);
1561 
        };
1562 
        if statuses.is_empty() {
1563 
            return Ok(None);
1564 
        }
1565 
        let _t = crate::timing::phase("snapshot: from the status cache");
1566 
        let (wc_hash, wc) = self.working_copy()?;
1567 
        let base = self.load_state_indexed(&wc.deps)?;
1568 
        let (base, base_snapshot) = self.render_base_for(&wc, base)?;
1569 
        let attribute_files: Vec<(String, Vec<u8>)> = match self.read_manifest()? {
1570 
            Some((_, _, m)) => m
1571 
                .entries
1572 
                .keys()
1573 
                .filter(|p| is_attributes(p))
1574 
                .filter_map(|p| fs::read(self.root.join(p)).ok().map(|b| (p.clone(), b)))
1575 
                .collect(),
1576 
            None => Vec::new(),
1577 
        };
1578 
        let attributes = crate::attributes::Attributes::from_files(
1579 
            attribute_files
1580 
                .iter()
1581 
                .map(|(p, b)| (p.as_str(), b.as_slice())),
1582 
        );
1583 
        Ok(Some(SnapshotResult {
1584 
            wc_hash,
1585 
            wc,
1586 
            base,
1587 
            base_snapshot,
1588 
            statuses,
1589 
            changed: false,
1590 
            resolves: false,
1591 
            contributors: Vec::new(),
1592 
            attributes,
1593 
            untracked_nested: self.untracked_nested.borrow().clone(),
1594 
        }))
77445673 Andy McCall ↶ 1595 
    }
1596
1597 
    /// The working-copy change with its base state and the base's
1598 
    /// rendering, for showing what the working copy changes. While the
1599 
    /// status cache holds (every file as the last snapshot left it), the
1600 
    /// stored working-copy change is the answer and no snapshot is taken;
1601 
    /// otherwise a snapshot makes it.
1602 
    pub fn working_copy_with_base(&self) -> Result<(Change, State, Snapshot)> {
1603 
        if self.status_by_manifest()?.is_some() {
1604 
            let (_, wc) = self.working_copy()?;
1605 
            let base = self.load_state_indexed(&wc.deps)?;
1606 
            let (base, snapshot) = self.render_base_for(&wc, base)?;
1607 
            return Ok((wc, base, snapshot));
1608 
        }
1609 
        let snap = self.snapshot_status("oxy diff")?;
1610 
        Ok((snap.wc, snap.base, snap.base_snapshot))
c6aa5bd9 Andy McCall ↶ 1611 
    }
1612
1613 
    /// The log restricted to changes touching `path` (its node, so renames
1614 
    /// are followed), on the current bookmark.
1615 
    pub fn log_for_path(&self, path: &str) -> Result<Vec<LogEntry>> {
e02bf0cd Andy McCall ↶ 1616 
        let heads = self.bookmark_heads()?;
1617 
        if self.is_bare() {
1618 
            return self.log_for_path_in(path, &heads);
1619 
        }
c6aa5bd9 Andy McCall ↶ 1620 
        let entries = self.log()?;
1621 
        let (_, wc) = self.working_copy()?;
1622 
        let base_snapshot = self.load_state(&wc.deps)?.materialize();
1623 
        let state_snapshot = self.load_state(&heads)?.materialize();
75167672 Andy McCall 1624 
        let node = base_snapshot
1625 
            .files
1626 
            .get(path)
1627 
            .or_else(|| state_snapshot.files.get(path))
1628 
            .map(|f| f.node);
1629 
        let Some(node) = node else {
1630 
            return fail(format!("{path} is not tracked"));
1631 
        };
e02bf0cd Andy McCall ↶ 1632 
        Ok(self.entries_touching(entries, node))
1633 
    }
1634
1635 
    /// The log of the state with these heads restricted to changes touching
1636 
    /// `path` (its node, so renames are followed).
1637 
    pub fn log_for_path_in(&self, path: &str, heads: &[ChangeHash]) -> Result<Vec<LogEntry>> {
e8d38e47 Andy McCall ↶ 1638 
        self.log_for_path_of(&self.load_state_history(heads)?, path, None)
bc489b6c Andy McCall ↶ 1639 
    }
1640
1641 
    /// The changes of a loaded state touching `path`, newest first, at most
1642 
    /// `limit` of them. The path is found in the state's tree alone, so no
1643 
    /// file is rendered, and the walk stops once `limit` are found.
1644 
    pub fn log_for_path_of(
1645 
        &self,
1646 
        state: &State,
1647 
        path: &str,
1648 
        limit: Option<usize>,
1649 
    ) -> Result<Vec<LogEntry>> {
1650 
        let Some(node) = state.tree().view().entries.get(path).map(|e| e.node) else {
75167672 Andy McCall 1651 
            return fail(format!("{path} is not in that state"));
1652 
        };
bc489b6c Andy McCall ↶ 1653 
        Ok(self.entries_touching_up_to(self.log_of(state), node, limit))
e02bf0cd Andy McCall ↶ 1654 
    }
1655
1656 
    fn entries_touching(&self, entries: Vec<LogEntry>, node: NodeId) -> Vec<LogEntry> {
bc489b6c Andy McCall ↶ 1657 
        self.entries_touching_up_to(entries, node, None)
1658 
    }
1659
1660 
    fn entries_touching_up_to(
1661 
        &self,
1662 
        entries: Vec<LogEntry>,
1663 
        node: NodeId,
1664 
        limit: Option<usize>,
1665 
    ) -> Vec<LogEntry> {
c6aa5bd9 Andy McCall ↶ 1666 
        let mut out = Vec::new();
1667 
        for e in entries {
bc489b6c Andy McCall ↶ 1668 
            if limit.is_some_and(|n| out.len() >= n) {
1669 
                break;
1670 
            }
75167672 Andy McCall 1671 
            let Ok(c) = self.store.get_change(&e.hash) else {
1672 
                continue;
1673 
            };
1674 
            if c.tree_ops.iter().any(|o| o.node() == node)
1675 
                || c.edits.iter().any(|x| x.node() == node)
1676 
            {
c6aa5bd9 Andy McCall ↶ 1677 
                out.push(e);
1678 
            }
1679 
        }
e02bf0cd Andy McCall ↶ 1680 
        out
c6aa5bd9 Andy McCall ↶ 1681 
    }
1682 
}
1683
1684 
/// Per-file hunks of `change` against `base`.
1685 
pub fn diff_files_of(change: &Change, base: &State, base_snapshot: &Snapshot) -> Vec<FileDiff> {
1686 
    let by_node = base_snapshot.tree.by_node();
1687 
    let mut new_names: HashMap<NodeId, (NodeId, String, NodeKind)> = HashMap::new();
1688 
    for op in &change.tree_ops {
75167672 Andy McCall 1689 
        if let TreeOp::AddNode {
1690 
            node,
1691 
            parent,
1692 
            name,
1693 
            kind,
1694 
            ..
1695 
        } = op
1696 
        {
c6aa5bd9 Andy McCall ↶ 1697 
            new_names.insert(*node, (*parent, name.clone(), *kind));
1698 
        }
1699 
    }
75167672 Andy McCall 1700 
    let path_of = |n: &NodeId| -> String {
1701 
        path_of_node(n, &by_node, &new_names).unwrap_or_else(|| format!("<node {}>", n.short(8)))
1702 
    };
c6aa5bd9 Andy McCall ↶ 1703 
    let mut files: BTreeMap<NodeId, FileDiff> = BTreeMap::new();
1704 
    let mut order: Vec<NodeId> = Vec::new();
1705 
    let mut entry = |files: &mut BTreeMap<NodeId, FileDiff>, n: NodeId, kind: &str| {
1706 
        if let std::collections::btree_map::Entry::Vacant(v) = files.entry(n) {
1707 
            order.push(n);
75167672 Andy McCall 1708 
            v.insert(FileDiff {
1709 
                path: path_of(&n),
1710 
                kind: kind.to_string(),
1711 
                hunks: vec![],
1712 
                from: None,
1713 
            });
c6aa5bd9 Andy McCall ↶ 1714 
        }
1715 
    };
1716 
    for op in &change.tree_ops {
1717 
        match op {
1718 
            TreeOp::AddNode { node, kind, .. } => {
1719 
                if *kind != NodeKind::Dir {
1720 
                    entry(&mut files, *node, "added");
1721 
                }
1722 
            }
1723 
            TreeOp::RemoveNode { node, .. } => {
1724 
                entry(&mut files, *node, "removed");
1725 
                if let Some(e) = by_node.get(node) {
1726 
                    files.get_mut(node).unwrap().path = e.path.clone();
1727 
                }
1728 
            }
75167672 Andy McCall 1729 
            TreeOp::Move {
1730 
                node, parent, name, ..
1731 
            } => {
c6aa5bd9 Andy McCall ↶ 1732 
                entry(&mut files, *node, "renamed");
1733 
                let f = files.get_mut(node).unwrap();
1734 
                f.from = by_node.get(node).map(|e| e.path.clone());
75167672 Andy McCall 1735 
                let dir = if parent.is_root() {
1736 
                    String::new()
1737 
                } else {
1738 
                    path_of_node(parent, &by_node, &new_names).unwrap_or_default()
1739 
                };
1740 
                f.path = if dir.is_empty() {
1741 
                    name.clone()
1742 
                } else {
1743 
                    format!("{dir}/{name}")
1744 
                };
c6aa5bd9 Andy McCall ↶ 1745 
            }
1746 
            TreeOp::SetMode { node, .. } => entry(&mut files, *node, "mode"),
1747 
        }
1748 
    }
1749 
    // Base line numbers per node, 1-based.
1750 
    let mut line_of: HashMap<NodeId, HashMap<(ChangeHash, u32), u32>> = HashMap::new();
1751 
    let mut lines_for = |n: &NodeId| -> HashMap<(ChangeHash, u32), u32> {
75167672 Andy McCall 1752 
        line_of
1753 
            .entry(*n)
1754 
            .or_insert_with(|| {
1755 
                base.live_lines(n)
1756 
                    .into_iter()
1757 
                    .enumerate()
1758 
                    .map(|(i, (k, _))| (k, i as u32 + 1))
1759 
                    .collect()
1760 
            })
1761 
            .clone()
c6aa5bd9 Andy McCall ↶ 1762 
    };
1763 
    for e in &change.edits {
1764 
        let n = e.node();
1765 
        let is_new = new_names.contains_key(&n);
1766 
        entry(&mut files, n, if is_new { "added" } else { "modified" });
1767 
        let f = files.get_mut(&n).unwrap();
1768 
        match e {
1769 
            Edit::Insert { after, lines, .. } => {
1770 
                let map = lines_for(&n);
1771 
                let base_line = match after {
1772 
                    AtomRef::Start => 0,
1773 
                    AtomRef::End => map.len() as u32,
75167672 Andy McCall 1774 
                    AtomRef::Atom { change, index } if change.is_zero() => {
1775 
                        f.hunks.last().map(|h| h.base_line).unwrap_or(0)
1776 
                    }
1777 
                    AtomRef::Atom { change, index } => {
1778 
                        map.get(&(*change, *index)).copied().unwrap_or(0)
1779 
                    }
c6aa5bd9 Andy McCall ↶ 1780 
                };
75167672 Andy McCall 1781 
                f.hunks.push(DiffHunk {
1782 
                    base_line,
01a47cd7 Andy McCall ↶ 1783 
                    added: lines.to_vec(),
75167672 Andy McCall 1784 
                    removed: vec![],
1785 
                });
c6aa5bd9 Andy McCall ↶ 1786 
            }
1787 
            Edit::Delete { atoms, .. } => {
1788 
                let map = lines_for(&n);
1789 
                let mut removed = Vec::new();
1790 
                for r in atoms {
1791 
                    for i in r.from..r.to {
1792 
                        let line = map.get(&(r.change, i)).copied().unwrap_or(0);
75167672 Andy McCall 1793 
                        let text = base
1794 
                            .file(&n)
1795 
                            .and_then(|g| g.content(&(r.change, i)))
1796 
                            .unwrap_or(b"")
1797 
                            .to_vec();
c6aa5bd9 Andy McCall ↶ 1798 
                        removed.push((line, text));
1799 
                    }
1800 
                }
75167672 Andy McCall 1801 
                let base_line = removed
1802 
                    .first()
1803 
                    .map(|(l, _)| l.saturating_sub(1))
1804 
                    .unwrap_or(0);
1805 
                f.hunks.push(DiffHunk {
1806 
                    base_line,
1807 
                    added: vec![],
1808 
                    removed,
1809 
                });
c6aa5bd9 Andy McCall ↶ 1810 
            }
1811 
            Edit::Replace { .. } => {
1812 
                if !is_new {
1813 
                    f.kind = "replaced".into();
1814 
                }
1815 
            }
1816 
        }
1817 
    }
1818 
    order.into_iter().filter_map(|n| files.remove(&n)).collect()
1819 
}
1820
98286406 Andy McCall ↶ 1821 
/// Builds the tree ops and edits of a working-copy change against a base.
dfb23a3a Andy McCall ↶ 1822 
/// `BLAKE3("oxy node 1" 0 seed kind path)`, truncated: a node identifier
1823 
/// that the same seed and path always give (never the root's).
1824 
fn seeded_node(seed: &[u8; 32], path: &str, kind: NodeKind) -> NodeId {
1825 
    let mut h = blake3::Hasher::new();
1826 
    h.update(b"oxy node 1\0");
1827 
    h.update(seed);
1828 
    h.update(&[match kind {
1829 
        NodeKind::File => 1,
1830 
        NodeKind::Dir => 2,
1831 
        NodeKind::Symlink => 3,
1832 
        NodeKind::Subrepo => 4,
1833 
    }]);
1834 
    h.update(path.as_bytes());
1835 
    let mut id = [0u8; 16];
1836 
    id.copy_from_slice(&h.finalize().as_bytes()[..16]);
1837 
    if id == [0; 16] {
1838 
        id[15] = 1;
1839 
    }
1840 
    NodeId(id)
1841 
}
1842
98286406 Andy McCall ↶ 1843 
struct ChangeBuilder<'a> {
1844 
    base: &'a State,
1845 
    base_snapshot: &'a Snapshot,
1846 
    tree_ops: Vec<TreeOp>,
1847 
    edits: Vec<Edit>,
1848 
    statuses: Vec<PathStatus>,
1849 
    dir_nodes: HashMap<String, NodeId>,
1850 
    reuse: HashMap<String, (NodeId, NodeKind)>,
1851 
    /// Changes that contributed to conflicts this working copy resolves.
1852 
    contributors: BTreeSet<ChangeHash>,
1853 
    resolves: bool,
cdb5beba Andy McCall ↶ 1854 
    attrs: crate::attributes::Attributes,
b7f102fc Andy McCall ↶ 1855 
    blobs: HashMap<String, ObjectRef>,
f7510b63 Andy McCall ↶ 1856 
    /// Opaque files whose replace conflict the content settles.
1857 
    resolve: HashSet<String>,
dfb23a3a Andy McCall ↶ 1858 
    /// When set, new nodes' identifiers derive from it and their paths.
1859 
    node_seed: Option<[u8; 32]>,
a87c7b9d Andy McCall ↶ 1860 
    /// For a Git import, the base's dead directories by where they were
1861 
    /// (see `ensure_dir`), worked out when first needed.
1862 
    dead_dirs: Option<HashMap<(NodeId, String), (NodeId, crate::tree::OpKey)>>,
98286406 Andy McCall ↶ 1863 
}
1864
1865 
impl<'a> ChangeBuilder<'a> {
75167672 Andy McCall 1866 
    fn new(
1867 
        base: &'a State,
1868 
        base_snapshot: &'a Snapshot,
1869 
        reuse: HashMap<String, (NodeId, NodeKind)>,
1870 
    ) -> Self {
98286406 Andy McCall ↶ 1871 
        let mut dir_nodes: HashMap<String, NodeId> = HashMap::new();
1872 
        dir_nodes.insert(String::new(), NodeId::ROOT);
e83354cd Andy McCall ↶ 1873 
        for (p, e) in base_snapshot.tree.entries.iter() {
2306a4d2 Andy McCall ↶ 1874 
            if e.kind == NodeKind::Dir {
1875 
                dir_nodes.insert(p.clone(), e.node);
98286406 Andy McCall ↶ 1876 
            }
1877 
        }
75167672 Andy McCall 1878 
        ChangeBuilder {
1879 
            base,
1880 
            base_snapshot,
1881 
            tree_ops: vec![],
1882 
            edits: vec![],
1883 
            statuses: vec![],
1884 
            dir_nodes,
1885 
            reuse,
1886 
            contributors: BTreeSet::new(),
1887 
            resolves: false,
1888 
            attrs: crate::attributes::Attributes::default(),
1889 
            blobs: HashMap::new(),
f7510b63 Andy McCall ↶ 1890 
            resolve: HashSet::new(),
dfb23a3a Andy McCall ↶ 1891 
            node_seed: None,
a87c7b9d Andy McCall ↶ 1892 
            dead_dirs: None,
75167672 Andy McCall 1893 
        }
98286406 Andy McCall ↶ 1894 
    }
1895
cdb5beba Andy McCall ↶ 1896 
    fn with_attributes(mut self, attrs: crate::attributes::Attributes) -> Self {
1897 
        self.attrs = attrs;
1898 
        self
1899 
    }
1900
1901 
    /// Whether a file is opaque: forced by `binary`, forced text by `text`
1902 
    /// only when it has no NUL bytes, else sniffed.
b7f102fc Andy McCall ↶ 1903 
    /// The blob for an opaque entry: the cached one, else stored now.
75167672 Andy McCall 1904 
    fn blob_of(
1905 
        &mut self,
1906 
        repo: &Repo,
1907 
        path: &str,
1908 
        e: &FsEntry,
1909 
        nocompress: bool,
1910 
    ) -> Result<ObjectRef> {
b7f102fc Andy McCall ↶ 1911 
        let b = match e.blob {
1912 
            Some(b) => b,
1913 
            None => repo.store_blob_for(&e.content, nocompress)?,
1914 
        };
1915 
        self.blobs.insert(path.to_string(), b);
1916 
        Ok(b)
1917 
    }
1918
cdb5beba Andy McCall ↶ 1919 
    fn opaque_for(&self, path: &str, e: &FsEntry) -> bool {
b7f102fc Andy McCall ↶ 1920 
        if e.blob.is_some() {
1921 
            return true;
1922 
        }
4dee277c Andy McCall ↶ 1923 
        if e.kind == NodeKind::Symlink || e.kind == NodeKind::Subrepo {
cdb5beba Andy McCall ↶ 1924 
            return true;
1925 
        }
1926 
        match self.attrs.lookup(path).binary {
1927 
            Some(true) => true,
1928 
            Some(false) => is_binary(&e.content),
1929 
            None => is_binary(&e.content),
1930 
        }
1931 
    }
1932
1933 
    /// Text content as stored: `\r\n` normalized for `eol=` files.
40a40bb7 Andy McCall ↶ 1934 
    fn stored_text(
1935 
        &self,
1936 
        path: &str,
1937 
        content: &std::sync::Arc<Vec<u8>>,
1938 
    ) -> std::sync::Arc<Vec<u8>> {
75167672 Andy McCall 1939 
        if self.attrs.lookup(path).eol.is_some() {
40a40bb7 Andy McCall ↶ 1940 
            std::sync::Arc::new(crate::attributes::normalize_eol(content))
75167672 Andy McCall 1941 
        } else {
40a40bb7 Andy McCall ↶ 1942 
            content.clone()
dfb23a3a Andy McCall ↶ 1943 
        }
1944 
    }
1945
1946 
    /// The identifier of a node added at `path`: reused when asked, derived
1947 
    /// from the seed when there is one, random otherwise.
1948 
    fn new_node(&self, path: &str, kind: NodeKind) -> NodeId {
1949 
        if let Some(n) = self.reused_node(path, kind) {
1950 
            return n;
75167672 Andy McCall 1951 
        }
dfb23a3a Andy McCall ↶ 1952 
        match &self.node_seed {
1953 
            Some(seed) => seeded_node(seed, path, kind),
1954 
            None => NodeId::random(),
1955 
        }
cdb5beba Andy McCall ↶ 1956 
    }
1957
98286406 Andy McCall ↶ 1958 
    fn reused_node(&self, path: &str, kind: NodeKind) -> Option<NodeId> {
75167672 Andy McCall 1959 
        self.reuse
1960 
            .get(path)
1961 
            .filter(|(_, k)| *k == kind)
1962 
            .map(|(n, _)| *n)
98286406 Andy McCall ↶ 1963 
    }
1964
a87c7b9d Andy McCall ↶ 1965 
    /// A dead directory last placed at (`parent`, `name`) in the base.
1966 
    fn revivable_dir(
1967 
        &mut self,
1968 
        parent: NodeId,
1969 
        name: &str,
1970 
    ) -> Option<(NodeId, crate::tree::OpKey)> {
1971 
        let base = self.base;
1972 
        self.dead_dirs
1973 
            .get_or_insert_with(|| base.tree().dead_dirs())
1974 
            .get(&(parent, name.to_string()))
1975 
            .copied()
1976 
    }
1977
98286406 Andy McCall ↶ 1978 
    fn ensure_dir(&mut self, path: &str) -> NodeId {
1979 
        if let Some(n) = self.dir_nodes.get(path) {
1980 
            return *n;
1981 
        }
1982 
        let mut parent = NodeId::ROOT;
1983 
        let mut prefix = String::new();
1984 
        for comp in path.split('/') {
1985 
            if !prefix.is_empty() {
1986 
                prefix.push('/');
1987 
            }
1988 
            prefix.push_str(comp);
a87c7b9d Andy McCall ↶ 1989 
            let known = self.dir_nodes.get(&prefix).copied();
1990 
            let revive = match known {
1991 
                Some(_) => None,
1992 
                None if self.node_seed.is_some() => self.revivable_dir(parent, comp),
1993 
                None => None,
1994 
            };
1995 
            parent = match (known, revive) {
1996 
                (Some(n), _) => n,
1997 
                (None, Some((node, old))) => {
1998 
                    // Git has no identity for a directory: one that comes
1999 
                    // back where it was is the same directory, brought back
2000 
                    // with a move, so lines of history that placed files in
2001 
                    // it before and after agree (oxygen#30).
2002 
                    self.tree_ops.push(TreeOp::Move {
2003 
                        node,
2004 
                        old: OpRef {
2005 
                            change: old.0,
2006 
                            index: old.1,
2007 
                        },
2008 
                        parent,
2009 
                        name: comp.to_string(),
2010 
                    });
2011 
                    self.dir_nodes.insert(prefix.clone(), node);
2012 
                    node
2013 
                }
2014 
                (None, None) => {
dfb23a3a Andy McCall ↶ 2015 
                    let node = self.new_node(&prefix, NodeKind::Dir);
75167672 Andy McCall 2016 
                    self.tree_ops.push(TreeOp::AddNode {
2017 
                        node,
2018 
                        kind: NodeKind::Dir,
2019 
                        mode: Mode::default(),
2020 
                        parent,
2021 
                        name: comp.to_string(),
2022 
                    });
98286406 Andy McCall ↶ 2023 
                    self.dir_nodes.insert(prefix.clone(), node);
2024 
                    node
2025 
                }
2026 
            };
2027 
        }
2028 
        parent
2029 
    }
2030
2031 
    fn add_path(&mut self, repo: &Repo, path: &str, e: &FsEntry) -> Result<()> {
2032 
        let (dir, name) = split_path(path);
2033 
        let parent = self.ensure_dir(dir);
dfb23a3a Andy McCall ↶ 2034 
        let node = self.new_node(path, e.kind);
cdb5beba Andy McCall ↶ 2035 
        let opaque = self.opaque_for(path, e);
2036 
        let nocompress = self.attrs.lookup(path).nocompress;
75167672 Andy McCall 2037 
        self.tree_ops.push(TreeOp::AddNode {
2038 
            node,
2039 
            kind: e.kind,
2040 
            mode: Mode {
2041 
                exec: e.exec,
2042 
                opaque,
2043 
            },
2044 
            parent,
2045 
            name: name.to_string(),
2046 
        });
98286406 Andy McCall ↶ 2047 
        if opaque {
b7f102fc Andy McCall ↶ 2048 
            let blob = self.blob_of(repo, path, e, nocompress)?;
75167672 Andy McCall 2049 
            self.edits.push(Edit::Replace {
2050 
                node,
2051 
                old: None,
2052 
                new: Some(blob),
2053 
            });
98286406 Andy McCall ↶ 2054 
        } else if !e.content.is_empty() {
cdb5beba Andy McCall ↶ 2055 
            let content = self.stored_text(path, &e.content);
98286406 Andy McCall ↶ 2056 
            self.edits.push(Edit::Insert {
2057 
                node,
2058 
                after: crate::objects::AtomRef::Start,
2059 
                before: crate::objects::AtomRef::End,
40a40bb7 Andy McCall ↶ 2060 
                lines: crate::lines::Lines::split_shared(content),
98286406 Andy McCall ↶ 2061 
            });
2062 
        }
75167672 Andy McCall 2063 
        self.statuses.push(PathStatus {
2064 
            path: path.to_string(),
2065 
            status: ChangeStatus::Added,
2066 
        });
98286406 Andy McCall ↶ 2067 
        Ok(())
2068 
    }
2069
6e723b81 Andy McCall ↶ 2070 
    /// Move the node at `old` to `new` and apply `e`'s content to it.
75167672 Andy McCall 2071 
    fn move_path(
2072 
        &mut self,
2073 
        repo: &Repo,
2074 
        old: &str,
2075 
        new: &str,
2076 
        e: &FsEntry,
2077 
        expected: &crate::state::FileState,
2078 
    ) -> Result<()> {
6e723b81 Andy McCall ↶ 2079 
        let entry = &self.base_snapshot.tree.entries[old];
2080 
        let (dir, name) = split_path(new);
2081 
        let parent = self.ensure_dir(dir);
75167672 Andy McCall 2082 
        self.tree_ops.push(TreeOp::Move {
2083 
            node: expected.node,
2084 
            old: op_ref(entry.placement),
2085 
            parent,
2086 
            name: name.to_string(),
2087 
        });
6e723b81 Andy McCall ↶ 2088 
        self.update_path(repo, old, e, expected)?;
2089 
        // update_path reports under the old path; the rename is what the user sees.
2090 
        self.statuses.retain(|s| s.path != old);
75167672 Andy McCall 2091 
        self.statuses.push(PathStatus {
2092 
            path: new.to_string(),
2093 
            status: ChangeStatus::Renamed,
2094 
        });
6e723b81 Andy McCall ↶ 2095 
        Ok(())
a87c7b9d Andy McCall ↶ 2096 
    }
2097
2098 
    /// For a Git import: a node the commit keeps is in one place, the one
2099 
    /// its tree names, so any other live placement it has in the base goes;
2100 
    /// and a node the tree cannot show at all (an orphan) goes too. Such a
2101 
    /// placement is out of sight, under a directory another line of history
2102 
    /// removed, where no diff of the tree would ever reach it (oxygen#30).
2103 
    fn retire_stray_placements(&mut self) {
2104 
        let mut retired: HashSet<(ChangeHash, u32)> = HashSet::new();
2105 
        let mut placed: BTreeSet<NodeId> = BTreeSet::new();
2106 
        for op in &self.tree_ops {
2107 
            match op {
2108 
                TreeOp::Move { node, old, .. } => {
2109 
                    retired.insert((old.change, old.index));
2110 
                    placed.insert(*node);
2111 
                }
2112 
                TreeOp::RemoveNode { placement, .. } => {
2113 
                    retired.insert((placement.change, placement.index));
2114 
                }
2115 
                TreeOp::AddNode { .. } | TreeOp::SetMode { .. } => {}
2116 
            }
2117 
        }
2118 
        // Nodes kept where they were: what the base's tree view shows and
2119 
        // this change neither moves nor removes.
2120 
        let mut kept: HashMap<NodeId, (ChangeHash, u32)> = HashMap::new();
2121 
        for e in self.base_snapshot.tree.entries.values() {
2122 
            if !retired.contains(&e.placement) {
2123 
                kept.insert(e.node, e.placement);
2124 
            }
2125 
        }
2126 
        // Only a node with several live placements can have a stray one,
2127 
        // and the tree view names each as a conflict.
2128 
        let multi: BTreeSet<NodeId> = self
2129 
            .base_snapshot
2130 
            .tree
2131 
            .conflicts
2132 
            .iter()
2133 
            .filter_map(|c| match c {
2134 
                crate::tree::TreeConflict::MultiPlacement { node, .. } => Some(*node),
2135 
                _ => None,
2136 
            })
2137 
            .collect();
2138 
        let mut extra = Vec::new();
2139 
        // A node whose only placements are under a directory another line
2140 
        // removed (an orphan) is nowhere the tree can show, and Git's tree
2141 
        // has no such path: it goes.
2142 
        for c in &self.base_snapshot.tree.conflicts {
2143 
            let crate::tree::TreeConflict::Orphan { node, .. } = c else {
2144 
                continue;
2145 
            };
2146 
            if kept.contains_key(node) || placed.contains(node) {
2147 
                continue;
2148 
            }
2149 
            for (k, _) in self.base.tree().live_placements(node) {
2150 
                if retired.insert(k) {
2151 
                    extra.push(TreeOp::RemoveNode {
2152 
                        node: *node,
2153 
                        placement: op_ref(k),
2154 
                    });
2155 
                }
2156 
            }
2157 
        }
2158 
        for node in placed
2159 
            .iter()
2160 
            .chain(multi.iter().filter(|n| kept.contains_key(*n)))
2161 
        {
2162 
            for (k, _) in self.base.tree().live_placements(node) {
2163 
                if retired.contains(&k) || kept.get(node) == Some(&k) {
2164 
                    continue;
2165 
                }
2166 
                retired.insert(k);
2167 
                extra.push(TreeOp::RemoveNode {
2168 
                    node: *node,
2169 
                    placement: op_ref(k),
2170 
                });
2171 
            }
2172 
        }
2173 
        if !extra.is_empty() {
2174 
            self.resolves = true;
2175 
            self.tree_ops.extend(extra);
2176 
        }
6e723b81 Andy McCall ↶ 2177 
    }
2178
98286406 Andy McCall ↶ 2179 
    fn remove_path(&mut self, path: &str, expected: &crate::state::FileState) {
2180 
        let entry = &self.base_snapshot.tree.entries[path];
75167672 Andy McCall 2181 
        self.tree_ops.push(TreeOp::RemoveNode {
2182 
            node: expected.node,
2183 
            placement: op_ref(entry.placement),
2184 
        });
98286406 Andy McCall ↶ 2185 
        if path.contains(".oxy-conflict-") || expected.is_conflicted() {
2186 
            self.resolves = true;
2187 
        }
75167672 Andy McCall 2188 
        self.statuses.push(PathStatus {
2189 
            path: path.to_string(),
2190 
            status: ChangeStatus::Removed,
2191 
        });
98286406 Andy McCall ↶ 2192 
    }
2193
75167672 Andy McCall 2194 
    fn update_path(
2195 
        &mut self,
2196 
        repo: &Repo,
2197 
        path: &str,
2198 
        e: &FsEntry,
2199 
        expected: &crate::state::FileState,
2200 
    ) -> Result<()> {
98286406 Andy McCall ↶ 2201 
        if expected.kind != e.kind {
2202 
            self.remove_path(path, expected);
2203 
            self.statuses.pop();
2204 
            self.add_path(repo, path, e)?;
2205 
            self.statuses.pop();
75167672 Andy McCall 2206 
            self.statuses.push(PathStatus {
2207 
                path: path.to_string(),
2208 
                status: ChangeStatus::Modified,
2209 
            });
98286406 Andy McCall ↶ 2210 
            return Ok(());
2211 
        }
2212 
        let entry = &self.base_snapshot.tree.entries[path];
2213 
        let node = expected.node;
2214 
        let mode_atom = entry.mode_atom.map(op_ref);
cc7a0056 Andy McCall ↶ 2215 
        if e.unchanged {
2216 
            // Known equal to the base's unconflicted rendering (spec
2217 
            // §12.3); only the executable bit can differ.
2218 
            if e.exec != expected.mode.exec {
2219 
                if let Some(old) = mode_atom {
2220 
                    self.tree_ops.push(TreeOp::SetMode {
2221 
                        node,
2222 
                        old,
2223 
                        mode: Mode {
2224 
                            exec: e.exec,
2225 
                            opaque: false,
2226 
                        },
2227 
                    });
2228 
                    self.statuses.push(PathStatus {
2229 
                        path: path.to_string(),
2230 
                        status: ChangeStatus::ModeChanged,
2231 
                    });
2232 
                }
2233 
            }
2234 
            return Ok(());
2235 
        }
98286406 Andy McCall ↶ 2236 
        let mut status: Option<ChangeStatus> = None;
cdb5beba Andy McCall ↶ 2237 
        let wants_opaque = self.opaque_for(path, e);
2238 
        let nocompress = self.attrs.lookup(path).nocompress;
2239 
        let disk_text = self.stored_text(path, &e.content);
98286406 Andy McCall ↶ 2240 
        match &expected.content {
2241 
            FileContent::Dir => {}
75167672 Andy McCall 2242 
            FileContent::Text {
2243 
                bytes,
2244 
                materialized,
2245 
            } => {
98286406 Andy McCall ↶ 2246 
                if materialized.is_conflicted() {
40a40bb7 Andy McCall ↶ 2247 
                    if bytes == &*disk_text {
98286406 Andy McCall ↶ 2248 
                        return Ok(());
2249 
                    }
2250 
                    if has_conflict_markers(&e.content) {
75167672 Andy McCall 2251 
                        self.statuses.push(PathStatus {
2252 
                            path: path.to_string(),
2253 
                            status: ChangeStatus::ConflictEdited,
2254 
                        });
98286406 Andy McCall ↶ 2255 
                        return Ok(());
2256 
                    }
2257 
                    // Resolution (spec §9.6): diff against the unconflicted lines
2258 
                    // with each region as a gap, then retire every region atom.
2259 
                    // Whatever the author kept from a region is re-inserted as
2260 
                    // new atoms, which leaves the graph totally ordered.
2261 
                    let regions = self.base.conflict_regions(&node);
cdb5beba Andy McCall ↶ 2262 
                    let mut edits = text_edits(node, &regions.plain, &disk_text);
98286406 Andy McCall ↶ 2263 
                    if !regions.region_atoms.is_empty() {
75167672 Andy McCall 2264 
                        edits.insert(
2265 
                            0,
2266 
                            Edit::Delete {
2267 
                                node,
2268 
                                atoms: ranges(&regions.region_atoms),
2269 
                            },
2270 
                        );
98286406 Andy McCall ↶ 2271 
                    }
2272 
                    self.edits.extend(edits);
2273 
                    self.contributors.extend(regions.contributors);
2274 
                    self.resolves = true;
2275 
                    if e.exec != expected.mode.exec {
2276 
                        if let Some(old) = mode_atom {
75167672 Andy McCall 2277 
                            self.tree_ops.push(TreeOp::SetMode {
2278 
                                node,
2279 
                                old,
2280 
                                mode: Mode {
2281 
                                    exec: e.exec,
2282 
                                    opaque: false,
2283 
                                },
2284 
                            });
98286406 Andy McCall ↶ 2285 
                        }
2286 
                    }
75167672 Andy McCall 2287 
                    self.statuses.push(PathStatus {
2288 
                        path: path.to_string(),
2289 
                        status: ChangeStatus::Resolved,
2290 
                    });
98286406 Andy McCall ↶ 2291 
                    return Ok(());
2292 
                }
cdb5beba Andy McCall ↶ 2293 
                if wants_opaque {
2294 
                    // Text → opaque (spec §7.5), by content or by attribute.
2295 
                    if let Some(old) = mode_atom {
75167672 Andy McCall 2296 
                        self.tree_ops.push(TreeOp::SetMode {
2297 
                            node,
2298 
                            old,
2299 
                            mode: Mode {
2300 
                                exec: e.exec,
2301 
                                opaque: true,
2302 
                            },
2303 
                        });
cdb5beba Andy McCall ↶ 2304 
                    }
2305 
                    let live: Vec<_> = repo_live_keys(self.base, &node);
2306 
                    if !live.is_empty() {
75167672 Andy McCall 2307 
                        self.edits.push(Edit::Delete {
2308 
                            node,
2309 
                            atoms: ranges(&live),
2310 
                        });
cdb5beba Andy McCall ↶ 2311 
                    }
b7f102fc Andy McCall ↶ 2312 
                    let blob = self.blob_of(repo, path, e, nocompress)?;
75167672 Andy McCall 2313 
                    self.edits.push(Edit::Replace {
2314 
                        node,
2315 
                        old: None,
2316 
                        new: Some(blob),
2317 
                    });
cdb5beba Andy McCall ↶ 2318 
                    status = Some(ChangeStatus::Modified);
40a40bb7 Andy McCall ↶ 2319 
                } else if bytes != &*disk_text {
2306a4d2 Andy McCall ↶ 2320 
                    let mut laps = crate::timing::Laps::start();
2321 
                    // The base's rendering holds its live atoms in order,
2322 
                    // one per line (it is not conflicted here).
2323 
                    let keys = materialized.live_atoms();
2324 
                    let lines = crate::diff::split_lines(bytes);
2325 
                    let edits = if keys.len() == lines.len() {
2326 
                        crate::diff::text_edits_of(node, &keys, &lines, &disk_text)
2327 
                    } else {
2328 
                        text_edits(node, &self.base.live_lines(&node), &disk_text)
2329 
                    };
2330 
                    laps.lap("build: text diff");
cdb5beba Andy McCall ↶ 2331 
                    if !edits.is_empty() {
2332 
                        self.edits.extend(edits);
98286406 Andy McCall ↶ 2333 
                        status = Some(ChangeStatus::Modified);
2334 
                    }
2335 
                }
cdb5beba Andy McCall ↶ 2336 
                let switched_to_opaque = wants_opaque;
98286406 Andy McCall ↶ 2337 
                if !switched_to_opaque && e.exec != expected.mode.exec {
2338 
                    if let Some(old) = mode_atom {
75167672 Andy McCall 2339 
                        self.tree_ops.push(TreeOp::SetMode {
2340 
                            node,
2341 
                            old,
2342 
                            mode: Mode {
2343 
                                exec: e.exec,
2344 
                                opaque: false,
2345 
                            },
2346 
                        });
98286406 Andy McCall ↶ 2347 
                        status.get_or_insert(ChangeStatus::ModeChanged);
2348 
                    }
2349 
                }
2350 
            }
2351 
            FileContent::Opaque { blobs } => {
b7f102fc Andy McCall ↶ 2352 
                let new_ref = e.blob.unwrap_or_else(|| Repo::blob_ref(&e.content));
2353 
                if e.kind == NodeKind::File && wants_opaque {
2354 
                    // Unchanged or replaced, the file stays opaque: remember its blob.
2355 
                    self.blobs.insert(path.to_string(), new_ref);
f7510b63 Andy McCall ↶ 2356 
                }
2357 
                if blobs.len() > 1 && self.resolve.contains(path) && e.kind == expected.kind {
2358 
                    // Settle the replace conflict (spec §9.3): replace every
2359 
                    // live candidate with the chosen blob, depending on each
2360 
                    // change that made one live, so all are superseded.
2361 
                    let chosen = self.blob_of(repo, path, e, nocompress)?;
2362 
                    for b in blobs {
2363 
                        self.edits.push(Edit::Replace {
2364 
                            node,
2365 
                            old: Some(*b),
2366 
                            new: Some(chosen),
2367 
                        });
2368 
                    }
2369 
                    self.contributors
2370 
                        .extend(self.base.blob_contributors(&node, blobs));
2371 
                    self.resolves = true;
2372 
                    self.statuses.push(PathStatus {
2373 
                        path: path.to_string(),
2374 
                        status: ChangeStatus::Resolved,
2375 
                    });
2376 
                    return Ok(());
b7f102fc Andy McCall ↶ 2377 
                }
98286406 Andy McCall ↶ 2378 
                if blobs.len() > 1 {
2379 
                    if !blobs.contains(&new_ref) {
75167672 Andy McCall 2380 
                        self.statuses.push(PathStatus {
2381 
                            path: path.to_string(),
2382 
                            status: ChangeStatus::ConflictEdited,
2383 
                        });
98286406 Andy McCall ↶ 2384 
                    }
2385 
                    return Ok(());
2386 
                }
2387 
                let current = blobs.first().copied();
2388 
                if current != Some(new_ref) {
cdb5beba Andy McCall ↶ 2389 
                    if e.kind == NodeKind::File && !wants_opaque {
98286406 Andy McCall ↶ 2390 
                        // Opaque → text (spec §7.5).
2391 
                        if let Some(old) = mode_atom {
75167672 Andy McCall 2392 
                            self.tree_ops.push(TreeOp::SetMode {
2393 
                                node,
2394 
                                old,
2395 
                                mode: Mode {
2396 
                                    exec: e.exec,
2397 
                                    opaque: false,
2398 
                                },
2399 
                            });
98286406 Andy McCall ↶ 2400 
                        }
75167672 Andy McCall 2401 
                        self.edits.push(Edit::Replace {
2402 
                            node,
2403 
                            old: current,
2404 
                            new: None,
2405 
                        });
98286406 Andy McCall ↶ 2406 
                        if !e.content.is_empty() {
2407 
                            self.edits.push(Edit::Insert {
2408 
                                node,
2409 
                                after: crate::objects::AtomRef::Start,
2410 
                                before: crate::objects::AtomRef::End,
01a47cd7 Andy McCall ↶ 2411 
                                lines: crate::lines::Lines::split(&e.content),
98286406 Andy McCall ↶ 2412 
                            });
2413 
                        }
2414 
                    } else {
b7f102fc Andy McCall ↶ 2415 
                        let blob = self.blob_of(repo, path, e, nocompress)?;
75167672 Andy McCall 2416 
                        self.edits.push(Edit::Replace {
2417 
                            node,
2418 
                            old: current,
2419 
                            new: Some(blob),
2420 
                        });
98286406 Andy McCall ↶ 2421 
                    }
2422 
                    status = Some(ChangeStatus::Modified);
2423 
                } else if e.kind == NodeKind::File && e.exec != expected.mode.exec {
2424 
                    if let Some(old) = mode_atom {
75167672 Andy McCall 2425 
                        self.tree_ops.push(TreeOp::SetMode {
2426 
                            node,
2427 
                            old,
2428 
                            mode: Mode {
2429 
                                exec: e.exec,
2430 
                                opaque: true,
2431 
                            },
2432 
                        });
98286406 Andy McCall ↶ 2433 
                        status = Some(ChangeStatus::ModeChanged);
2434 
                    }
2435 
                }
2436 
            }
2437 
        }
2438 
        if let Some(s) = status {
75167672 Andy McCall 2439 
            self.statuses.push(PathStatus {
2440 
                path: path.to_string(),
2441 
                status: s,
2442 
            });
98286406 Andy McCall ↶ 2443 
        }
2444 
        Ok(())
2445 
    }
2446 
}
2447
2448 
fn repo_live_keys(base: &State, node: &NodeId) -> Vec<crate::graph::AtomKey> {
2449 
    base.live_lines(node).into_iter().map(|(k, _)| k).collect()
2450 
}
2451
2452 
/// The changes a change's scope references (spec §8.1): introducers of every
2453 
/// atom, placement, and mode it touches, and of every node it operates on.
2454 
pub fn referenced_changes(change: &Change, base: &State) -> BTreeSet<ChangeHash> {
2455 
    let mut out = BTreeSet::new();
2456 
    let opref = |r: &OpRef, out: &mut BTreeSet<ChangeHash>| {
2457 
        if !r.change.is_zero() {
2458 
            out.insert(r.change);
2459 
        }
2460 
    };
2461 
    let mut nodes: Vec<NodeId> = Vec::new();
2462 
    for op in &change.tree_ops {
2463 
        match op {
2464 
            TreeOp::AddNode { parent, .. } => nodes.push(*parent),
2465 
            TreeOp::RemoveNode { node, placement } => {
2466 
                nodes.push(*node);
2467 
                opref(placement, &mut out);
2468 
            }
75167672 Andy McCall 2469 
            TreeOp::Move {
2470 
                node, old, parent, ..
2471 
            } => {
98286406 Andy McCall ↶ 2472 
                nodes.push(*node);
2473 
                nodes.push(*parent);
2474 
                opref(old, &mut out);
2475 
            }
2476 
            TreeOp::SetMode { node, old, .. } => {
2477 
                nodes.push(*node);
2478 
                opref(old, &mut out);
2479 
            }
2480 
        }
2481 
    }
2482 
    for e in &change.edits {
2483 
        nodes.push(e.node());
2484 
        match e {
2485 
            Edit::Insert { after, before, .. } => {
2486 
                for r in [after, before] {
2487 
                    if let crate::objects::AtomRef::Atom { change, .. } = r {
2488 
                        if !change.is_zero() {
2489 
                            out.insert(*change);
2490 
                        }
2491 
                    }
2492 
                }
2493 
            }
2494 
            Edit::Delete { atoms, .. } => {
62794ecc Andy McCall ↶ 2495 
                // Deleting an atom also depends on whoever inserted the live
2496 
                // atoms right after it: the author saw those insertions, and
2497 
                // without the dependency spec §9.1 would call the deletion
2498 
                // concurrent with them (a delete/insert conflict).
2499 
                let graph = base.file(&e.node());
98286406 Andy McCall ↶ 2500 
                for r in atoms {
2501 
                    if !r.change.is_zero() {
2502 
                        out.insert(r.change);
2503 
                    }
62794ecc Andy McCall ↶ 2504 
                    if let Some(g) = graph {
2505 
                        for i in r.from..r.to {
2506 
                            out.extend(
2507 
                                g.live_successor_changes(&(r.change, i))
2508 
                                    .into_iter()
2509 
                                    .filter(|c| !c.is_zero()),
2510 
                            );
2511 
                        }
2512 
                    }
98286406 Andy McCall ↶ 2513 
                }
2514 
            }
62794ecc Andy McCall ↶ 2515 
            // Replacing a blob depends on the change that made it current,
2516 
            // as deleting a line depends on the line's introducer.
2517 
            Edit::Replace {
2518 
                node,
2519 
                old: Some(old),
2520 
                ..
2521 
            } => {
2522 
                out.extend(
2523 
                    base.live_replaces(node)
2524 
                        .into_iter()
2525 
                        .filter(|(c, b)| b == old && !c.is_zero())
2526 
                        .map(|(c, _)| c),
2527 
                );
2528 
            }
98286406 Andy McCall ↶ 2529 
            Edit::Replace { .. } => {}
2530 
        }
2531 
    }
2532 
    for n in nodes {
2533 
        if let Some(h) = base.tree().introducer(&n) {
2534 
            out.insert(h);
2535 
        }
2536 
    }
2537 
    out
2538 
}
2539
2540 
/// Paths of the nodes a change adds on top of `base_snapshot`.
75167672 Andy McCall 2541 
pub fn added_node_paths(
2542 
    change: &Change,
2543 
    base_snapshot: &Snapshot,
2544 
) -> HashMap<String, (NodeId, NodeKind)> {
98286406 Andy McCall ↶ 2545 
    let by_node = base_snapshot.tree.by_node();
2546 
    let mut new_names: HashMap<NodeId, (NodeId, String, NodeKind)> = HashMap::new();
2547 
    for op in &change.tree_ops {
75167672 Andy McCall 2548 
        if let TreeOp::AddNode {
2549 
            node,
2550 
            parent,
2551 
            name,
2552 
            kind,
2553 
            ..
2554 
        } = op
2555 
        {
98286406 Andy McCall ↶ 2556 
            new_names.insert(*node, (*parent, name.clone(), *kind));
2557 
        }
2558 
    }
2559 
    let mut out = HashMap::new();
2560 
    for (node, (_, _, kind)) in &new_names {
2561 
        if let Some(path) = path_of_node(node, &by_node, &new_names) {
2562 
            out.insert(path, (*node, *kind));
2563 
        }
2564 
    }
2565 
    out
2566 
}
2567
2568 
fn path_of_node(
2569 
    n: &NodeId,
2570 
    by_node: &HashMap<NodeId, &crate::tree::TreeEntry>,
2571 
    new_names: &HashMap<NodeId, (NodeId, String, NodeKind)>,
2572 
) -> Option<String> {
2573 
    if let Some(e) = by_node.get(n) {
2574 
        return Some(e.path.clone());
2575 
    }
2576 
    let mut parts = Vec::new();
2577 
    let mut cur = *n;
2578 
    loop {
2579 
        if cur.is_root() {
2580 
            break;
2581 
        }
2582 
        if let Some(e) = by_node.get(&cur) {
2583 
            if !e.path.is_empty() {
2584 
                parts.push(e.path.clone());
2585 
            }
2586 
            break;
2587 
        }
2588 
        let (parent, name, _) = new_names.get(&cur)?;
2589 
        parts.push(name.clone());
2590 
        cur = *parent;
2591 
    }
2592 
    parts.reverse();
2593 
    Some(parts.join("/"))
2594 
}
2595
2596 
/// Render a change's operations with line content, using `base` for deleted lines.
2597 
pub fn render_change(change: &Change, base: &State, base_snapshot: &Snapshot) -> String {
2598 
    let by_node = base_snapshot.tree.by_node();
2599 
    let mut new_names: HashMap<NodeId, (NodeId, String, NodeKind)> = HashMap::new();
2600 
    for op in &change.tree_ops {
75167672 Andy McCall 2601 
        if let TreeOp::AddNode {
2602 
            node,
2603 
            parent,
2604 
            name,
2605 
            kind,
2606 
            ..
2607 
        } = op
2608 
        {
98286406 Andy McCall ↶ 2609 
            new_names.insert(*node, (*parent, name.clone(), *kind));
2610 
        }
2611 
    }
75167672 Andy McCall 2612 
    let path_of = |n: &NodeId| -> String {
2613 
        path_of_node(n, &by_node, &new_names).unwrap_or_else(|| format!("<node {}>", n.short(8)))
2614 
    };
98286406 Andy McCall ↶ 2615
2616 
    let mut out = String::new();
2617 
    for op in &change.tree_ops {
2618 
        match op {
75167672 Andy McCall 2619 
            TreeOp::AddNode {
2620 
                node, kind, mode, ..
2621 
            } => {
2622 
                out.push_str(&format!(
2623 
                    "A {} ({:?}{}{})\n",
2624 
                    path_of(node),
2625 
                    kind,
2626 
                    if mode.exec { ", exec" } else { "" },
2627 
                    if mode.opaque { ", opaque" } else { "" }
2628 
                ));
98286406 Andy McCall ↶ 2629 
            }
2630 
            TreeOp::RemoveNode { node, .. } => out.push_str(&format!("D {}\n", path_of(node))),
75167672 Andy McCall 2631 
            TreeOp::Move { node, name, .. } => {
2632 
                out.push_str(&format!("R {} -> {}\n", path_of(node), name))
2633 
            }
98286406 Andy McCall ↶ 2634 
            TreeOp::SetMode { node, mode, .. } => {
75167672 Andy McCall 2635 
                out.push_str(&format!(
2636 
                    "M {} mode: exec={} opaque={}\n",
2637 
                    path_of(node),
2638 
                    mode.exec,
2639 
                    mode.opaque
2640 
                ));
98286406 Andy McCall ↶ 2641 
            }
2642 
        }
2643 
    }
2644 
    let mut last_node: Option<NodeId> = None;
2645 
    for e in &change.edits {
2646 
        let n = e.node();
2647 
        if last_node != Some(n) {
2648 
            out.push_str(&format!("--- {}\n", path_of(&n)));
2649 
            last_node = Some(n);
2650 
        }
2651 
        match e {
2652 
            Edit::Insert { lines, .. } => {
01a47cd7 Andy McCall ↶ 2653 
                for l in lines.iter() {
98286406 Andy McCall ↶ 2654 
                    out.push('+');
2655 
                    out.push_str(&String::from_utf8_lossy(l));
2656 
                    if !l.ends_with(b"\n") {
2657 
                        out.push('\n');
2658 
                    }
2659 
                }
2660 
            }
2661 
            Edit::Delete { atoms, .. } => {
2662 
                for r in atoms {
2663 
                    for i in r.from..r.to {
75167672 Andy McCall 2664 
                        let content = base
2665 
                            .file(&n)
2666 
                            .and_then(|g| g.content(&(r.change, i)))
2667 
                            .unwrap_or(b"<unknown>\n");
98286406 Andy McCall ↶ 2668 
                        out.push('-');
2669 
                        out.push_str(&String::from_utf8_lossy(content));
2670 
                        if !content.ends_with(b"\n") {
2671 
                            out.push('\n');
2672 
                        }
2673 
                    }
2674 
                }
2675 
            }
2676 
            Edit::Replace { old, new, .. } => {
2677 
                out.push_str(&format!(
2678 
                    "  opaque content {} -> {}\n",
2679 
                    old.map(|o| o.short(12)).unwrap_or_else(|| "none".into()),
2680 
                    new.map(|o| o.short(12)).unwrap_or_else(|| "none".into())
2681 
                ));
2682 
            }
2683 
        }
2684 
    }
2685 
    out
2686 
}
6e723b81 Andy McCall ↶ 2687
2688 
/// Pair removed files with added files of the same kind whose contents are
2689 
/// at least `RENAME_THRESHOLD` percent alike, best matches first. Beyond
2690 
/// `RENAME_LIMIT` candidate pairs only identical contents are paired.
2691 
const RENAME_THRESHOLD: u32 = 50;
2692 
const RENAME_LIMIT: usize = 10_000;
2306a4d2 Andy McCall ↶ 2693
23ff1288 Andy McCall ↶ 2694 
/// How a change is built beyond its entries: for a Git import, the seed
2695 
/// its new nodes' identifiers derive from; and, when it is built from part
2696 
/// of the tree, whether the new tree has anything under a directory.
2697 
#[derive(Default)]
2698 
struct Scope<'a> {
2699 
    seed: Option<[u8; 32]>,
2306a4d2 Andy McCall ↶ 2700 
    dir_needed: Option<&'a dyn Fn(&str) -> bool>,
2701 
}
6e723b81 Andy McCall ↶ 2702
75167672 Andy McCall 2703 
fn detect_renames(
2704 
    base_snapshot: &Snapshot,
2705 
    fs_entries: &BTreeMap<String, FsEntry>,
2706 
    in_scope: impl Fn(&str) -> bool,
2707 
) -> Vec<(String, String)> {
6e723b81 Andy McCall ↶ 2708 
    let removed: Vec<(&String, &crate::state::FileState)> = base_snapshot
2709 
        .files
2710 
        .iter()
75167672 Andy McCall 2711 
        .filter(|(p, f)| {
2712 
            f.kind != NodeKind::Dir
2713 
                && !fs_entries.contains_key(*p)
2714 
                && in_scope(p)
2715 
                && !f.is_conflicted()
2716 
        })
2717 
        .collect();
2718 
    let added: Vec<(&String, &FsEntry)> = fs_entries
2719 
        .iter()
2720 
        .filter(|(p, e)| e.kind != NodeKind::Dir && !base_snapshot.files.contains_key(*p))
6e723b81 Andy McCall ↶ 2721 
        .collect();
2722 
    if removed.is_empty() || added.is_empty() {
2723 
        return vec![];
2724 
    }
2725 
    let exact_only = removed.len() * added.len() > RENAME_LIMIT;
2726 
    let old_content = |f: &crate::state::FileState| -> Option<Vec<u8>> {
2727 
        match &f.content {
2728 
            FileContent::Text { bytes, .. } => Some(bytes.clone()),
2729 
            _ => None,
2730 
        }
2731 
    };
2732 
    let mut scored: Vec<(u32, usize, usize)> = Vec::new();
2733 
    for (ri, (_, f)) in removed.iter().enumerate() {
2734 
        let old = old_content(f);
2735 
        let old_blob = match &f.content {
2736 
            FileContent::Opaque { blobs } if blobs.len() == 1 => Some(blobs[0]),
2737 
            _ => None,
2738 
        };
2739 
        for (ai, (_, e)) in added.iter().enumerate() {
2740 
            if e.kind != f.kind {
2741 
                continue;
2742 
            }
2743 
            let score = match (&old, old_blob) {
2744 
                (Some(o), _) => {
2745 
                    if exact_only {
40a40bb7 Andy McCall ↶ 2746 
                        if *o == *e.content {
75167672 Andy McCall 2747 
                            100
2748 
                        } else {
2749 
                            0
2750 
                        }
6e723b81 Andy McCall ↶ 2751 
                    } else {
2752 
                        similarity(o, &e.content)
2753 
                    }
2754 
                }
b7f102fc Andy McCall ↶ 2755 
                (None, Some(b)) if e.blob.unwrap_or_else(|| Repo::blob_ref(&e.content)) == b => 100,
6e723b81 Andy McCall ↶ 2756 
                _ => 0,
2757 
            };
2758 
            if score >= RENAME_THRESHOLD {
2759 
                scored.push((score, ri, ai));
2760 
            }
2761 
        }
2762 
    }
75167672 Andy McCall 2763 
    scored.sort_by(|a, b| {
2764 
        b.0.cmp(&a.0)
2765 
            .then(removed[a.1].0.cmp(removed[b.1].0))
2766 
            .then(added[a.2].0.cmp(added[b.2].0))
2767 
    });
6e723b81 Andy McCall ↶ 2768 
    let mut used_r = vec![false; removed.len()];
2769 
    let mut used_a = vec![false; added.len()];
2770 
    let mut out = Vec::new();
2771 
    for (_, ri, ai) in scored {
2772 
        if used_r[ri] || used_a[ai] {
2773 
            continue;
2774 
        }
2775 
        used_r[ri] = true;
2776 
        used_a[ai] = true;
2777 
        out.push((removed[ri].0.clone(), added[ai].0.clone()));
2778 
    }
2779 
    out
2780 
}
2781
2782 
/// Percentage of the larger file's bytes found in lines the two share
2783 
/// (multiset intersection of lines), like Git's similarity index.
2784 
pub fn similarity(a: &[u8], b: &[u8]) -> u32 {
2785 
    if a == b {
2786 
        return 100;
2787 
    }
2788 
    if a.is_empty() || b.is_empty() {
2789 
        return 0;
2790 
    }
2791 
    let mut counts: HashMap<&[u8], usize> = HashMap::new();
2792 
    for l in split_lines(a) {
2793 
        *counts.entry(l).or_default() += 1;
2794 
    }
2795 
    let mut shared = 0usize;
2796 
    for l in split_lines(b) {
2797 
        if let Some(n) = counts.get_mut(l) {
2798 
            if *n > 0 {
2799 
                *n -= 1;
2800 
                shared += l.len();
2801 
            }
2802 
        }
2803 
    }
2804 
    (shared * 100 / a.len().max(b.len())) as u32
d616faf5 Andy McCall ↶ 2805 
}
2806
2807 
/// Two maps side by side in key order: each key of either, with its value
2808 
/// in each. Linear, with no lookups, for maps of a whole tree.
2809 
fn join<'a, A, B>(
2810 
    a: &'a BTreeMap<String, A>,
2811 
    b: &'a BTreeMap<String, B>,
2812 
) -> impl Iterator<Item = (&'a String, Option<&'a A>, Option<&'a B>)> {
2813 
    let (mut a, mut b) = (a.iter().peekable(), b.iter().peekable());
2814 
    std::iter::from_fn(move || match (a.peek(), b.peek()) {
2815 
        (None, None) => None,
2816 
        (Some(_), None) => a.next().map(|(k, v)| (k, Some(v), None)),
2817 
        (None, Some(_)) => b.next().map(|(k, v)| (k, None, Some(v))),
2818 
        (Some((ka, _)), Some((kb, _))) => match ka.cmp(kb) {
2819 
            std::cmp::Ordering::Less => a.next().map(|(k, v)| (k, Some(v), None)),
2820 
            std::cmp::Ordering::Greater => b.next().map(|(k, v)| (k, None, Some(v))),
2821 
            std::cmp::Ordering::Equal => {
2822 
                let (k, va) = a.next()?;
2823 
                let (_, vb) = b.next()?;
2824 
                Some((k, Some(va), Some(vb)))
2825 
            }
2826 
        },
2827 
    })
2828 
}
2829
2830 
#[cfg(test)]
2831 
mod join_tests {
2832 
    use super::*;
2833
2834 
    #[test]
2835 
    fn join_pairs_every_key_in_order() {
2836 
        let a: BTreeMap<String, u8> = [("a", 1), ("b/c", 2), ("d", 3)]
2837 
            .into_iter()
2838 
            .map(|(k, v)| (k.to_string(), v))
2839 
            .collect();
2840 
        let b: BTreeMap<String, char> = [("b", 'x'), ("b/c", 'y'), ("e", 'z')]
2841 
            .into_iter()
2842 
            .map(|(k, v)| (k.to_string(), v))
2843 
            .collect();
2844 
        let got: Vec<(String, Option<u8>, Option<char>)> = join(&a, &b)
2845 
            .map(|(k, x, y)| (k.clone(), x.copied(), y.copied()))
2846 
            .collect();
2847 
        let want = vec![
2848 
            ("a".to_string(), Some(1), None),
2849 
            ("b".to_string(), None, Some('x')),
2850 
            ("b/c".to_string(), Some(2), Some('y')),
2851 
            ("d".to_string(), Some(3), None),
2852 
            ("e".to_string(), None, Some('z')),
2853 
        ];
2854 
        assert_eq!(got, want);
2855 
    }
6e723b81 Andy McCall ↶ 2856 
}