OXYGENHUB
◆ v0.2.0 oxygen / crates / oxy-core / src / repo / mod.rs
83.4 KiB · Rust · last changed The operation log says what each operation did; op restore, op revert and --at-op; commands say where they left you (closes #51, closes #52, closes #53) 1 month ago source blame history raw
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//! A repository on disk: the `.oxy` directory, one workspace, the operation
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//! log, and the working-copy change (spec §12, §13.1).
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//!
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//! Not yet implemented from the spec: packs, checkpoints, multiple
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//! workspaces, multi-signer policy updates, and the `objects`/`checkpoint`
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//! endpoints. A repository without a policy is unverified and accepts
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//! unsigned pushes; with one, everything received is checked (spec §14.5). Changes are signed individually when `core.sign` is
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//! `change`; the default `seal` leaves them unsigned until push exists.
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use crate::attest::{Attest, AttestBody};
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use crate::diff::{ranges, split_lines, text_edits};
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use crate::hash::{hash_object, ChangeHash, KeyId, ObjectRef, ObjectType};
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use crate::identity::{verify as verify_signature, Domain, Identity, SecretKey, Signature};
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use crate::ids::{ChangeId, NodeId, WorkspaceId};
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use crate::objects::{
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    Blob, Change, ChangeKind, Edit, Hlc, Mode, NodeKind, OpRef, StateObject, TreeOp,
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};
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use crate::oplog::{Format1Op, Op, View, SNAPSHOT_SUFFIX};
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use crate::protocol::{
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    open_remote, Bundle, RefResult, RefUpdate, RefsResponse, RemoteOptions, RemoteRef,
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    SignedAttest, SignedPolicy,
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};
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use crate::state::{FileContent, Snapshot, State};
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use crate::store::{Store, StoreError};
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#[allow(unused_imports)]
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use crate::subrepo::Pin;
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use crate::tree::OpKey;
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use rand::RngCore;
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use std::collections::{BTreeMap, BTreeSet, HashMap, HashSet};
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use std::fs;
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use std::io::Write;
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use std::path::{Path, PathBuf};
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pub const OXY_DIR: &str = ".oxy";
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pub const FORMAT_LINE: &str = "oxy repository format 2\n";
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const FORMAT1_LINE: &str = "oxy repository format 1\n";
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const BINARY_SNIFF: usize = 8 * 1024;
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/// Loose objects tolerated before a commit packs them (spec §13.4).
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pub const AUTOPACK_THRESHOLD: usize = 4096;
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#[derive(Debug, thiserror::Error)]
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pub enum RepoError {
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    #[error("io: {0}")]
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    Io(#[from] std::io::Error),
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    #[error(transparent)]
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    Store(#[from] StoreError),
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    #[error(transparent)]
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    Object(#[from] crate::objects::ObjectError),
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    #[error(transparent)]
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    State(#[from] crate::state::StateError),
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    #[error("{0}")]
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    Msg(String),
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    /// The operation would leave a conflict where none may be (a rebased
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    /// change cannot hold one); the caller may offer another way.
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    #[error("{0}")]
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    Conflicted(String),
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}
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pub type Result<T> = std::result::Result<T, RepoError>;
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fn fail<T>(s: impl Into<String>) -> Result<T> {
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    Err(RepoError::Msg(s.into()))
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}
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mod bookmarks;
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mod checkout;
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mod checkpoint;
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mod config;
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mod doctor;
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mod fsck;
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mod gc;
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mod git;
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mod history;
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mod hooks;
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mod hosted;
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mod identity;
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mod inspect;
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mod ops;
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mod policy;
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mod prompt;
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mod receipts;
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mod snapshot;
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mod subrepos;
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mod sync;
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mod tags;
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#[cfg(test)]
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mod tests;
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mod walk;
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mod workspace;
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pub use bookmarks::{remote_bookmark, BookmarkInfo, MergeReport, RemoteOnlyBookmark, StateGap};
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pub use checkout::CheckoutReport;
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pub use config::{parse_size, read_config_file, Config};
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pub use doctor::{Check, DoctorReport, Health};
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pub use fsck::{FsckReport, Problem, Severity};
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pub use gc::GcReport;
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pub use git::{GitExportReport, GitImportReport, GitVerifyReport};
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pub use hooks::{json_array, json_str, HookOutcome};
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pub use hosted::FileEdit;
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pub use identity::{Rotation, SignatureStatus};
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pub use inspect::{BisectStep, BlameLine, Description};
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pub use ops::{RestoreReport, RevertReport, ViewChange};
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pub use policy::PolicyUpdate;
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pub use prompt::{PromptInfo, DEFAULT_PROMPT_FORMAT, GLYPH_PROMPT_FORMAT};
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pub use receipts::ReceiptInfo;
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pub use snapshot::{
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    added_node_paths, diff_files_of, has_conflict_markers, is_binary, referenced_changes,
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    render_change, render_hunks, similarity, ChangeStatus, DiffHunk, FileDiff, Hunk, PathStatus,
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    Selection, SnapshotResult,
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};
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pub use subrepos::{SubrepoInfo, SubrepoSync};
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pub use sync::{FetchReport, PullReport, PushReport, RefUpdated};
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pub use tags::TagInfo;
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pub use workspace::{FileLock, SnapshotLock, WorkingCopyLock, WorkspaceInfo};
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/// The file name under which per-bookmark or per-tag data is kept: `/`
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/// (and `%`) escaped, so `feature/x` is one file beside `feature` rather
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/// than a directory that would clash with it.
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pub(crate) fn name_file(name: &str) -> String {
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    name.replace('%', "%25").replace('/', "%2F")
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}
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/// The name a [`name_file`] file name stands for.
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pub(crate) fn file_name_to_name(file: &str) -> String {
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    file.replace("%2F", "/").replace("%25", "%")
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}
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fn write_atomic(path: &Path, data: &[u8]) -> Result<()> {
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    Ok(crate::durable::write_atomic(path, data)?)
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}
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/// Replace a cache file: whole or not at all, but without waiting for the
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/// disk. A cache checks its own bytes when read, so one a crash leaves
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/// short or stale is rebuilt rather than trusted.
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/// How many changes a state index may fall behind its working copy before
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/// it is written again; until then each load replays them.
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const INDEX_REPLAY_LIMIT: usize = 16;
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/// The changes whose encodings are kept for building graphs: a batch of
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/// files often takes inline text from a few changes in turn.
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const CHANGE_CACHE_COUNT: usize = 4;
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const CHANGE_CACHE_BYTES: usize = 512 << 20;
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/// How many state indexes a workspace keeps.
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const STATE_INDEXES_KEPT: usize = 2;
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const INDEX_REPLAY_TIME: std::time::Duration = std::time::Duration::from_millis(50);
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pub(crate) fn write_cache(path: &Path, data: &[u8]) -> Result<()> {
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    let tmp = path.with_extension(format!("tmp-{}", std::process::id()));
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    fs::write(&tmp, data)?;
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    fs::rename(&tmp, path)?;
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    Ok(())
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}
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pub struct LogEntry {
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    pub hash: ChangeHash,
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    /// Metadata from the state; the full change may be absent in a shallow repository.
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    pub change: crate::state::ChangeMeta,
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    pub is_working_copy: bool,
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    pub is_head: bool,
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}
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/// A text file's base graph key, by path, as a walk asks for it.
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pub(crate) type KeyOf<'a> = dyn Fn(&str) -> Option<[u8; 32]> + Sync + 'a;
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/// A file as found on disk or in an imported tree.
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#[derive(Clone)]
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pub(crate) struct FsEntry {
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    pub kind: NodeKind,
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    pub exec: bool,
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    /// File content, or a symlink's target. Empty when `blob` is set.
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    /// Shared, so a new file's insert holds it without a copy.
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    pub content: std::sync::Arc<Vec<u8>>,
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    /// The stored blob of an opaque file whose size and mtime are unchanged
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    /// since the last manifest (spec §12.3 stat cache); the content was not
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    /// read.
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    pub blob: Option<ObjectRef>,
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    /// BLAKE3 of the content, carried over from the manifest when the stat
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    /// is unchanged, so the manifest can be rewritten without rehashing.
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    pub content_hash: Option<[u8; 32]>,
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    /// A text file known equal to the base's rendering without reading it:
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    /// its stat matches the manifest and the manifest recorded it equal to
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    /// a base file graph with the same key (spec §12.3). `content` is empty.
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    pub unchanged: bool,
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    /// The base graph key this file equals, for the next manifest.
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    pub graph_key: Option<[u8; 32]>,
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    /// Size and mtime already known to be current (a checkout leaving the
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    /// file as it was), so the manifest need not stat it again.
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    pub stat: Option<(u64, u128)>,
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}
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impl FsEntry {
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    pub(crate) fn new(kind: NodeKind, exec: bool, content: Vec<u8>) -> FsEntry {
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        FsEntry {
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            kind,
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            exec,
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            content: std::sync::Arc::new(content),
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            blob: None,
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            content_hash: None,
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            unchanged: false,
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            graph_key: None,
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            stat: None,
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        }
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    }
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}
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pub struct Repo {
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    /// Oxygen-pinned subrepos skipped by the running Git export.
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    pub(crate) git_export_skipped: std::cell::Cell<usize>,
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    /// The manifest as last read, with the file identity it was read from,
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    /// so one command parses it once (see `read_manifest`).
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    pub(crate) manifest_cache: std::cell::RefCell<Option<prompt::CachedManifest>>,
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    /// A listing of the working copy left by a failed clean check, for the
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    /// snapshot that follows it to reuse; taken by the next walk and
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    /// dropped whenever the manifest is written.
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    pub(crate) listing_cache: std::cell::RefCell<Option<walk::Listing>>,
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    /// The nested repositories the last walk left out, being neither
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    /// registered nor tracked subrepos (oxygen#43).
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    pub(crate) untracked_nested: std::cell::RefCell<Vec<String>>,
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    root: PathBuf,
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    oxy: PathBuf,
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    store: Store,
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    workspace: WorkspaceId,
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    /// A hosted repository with no working copy (spec §12.2, hub spec §4.1).
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    bare: bool,
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    keys_dir: PathBuf,
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    user_config: PathBuf,
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    pub config: Config,
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    /// What the working copy's file system can represent (spec §7.7).
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    platform: crate::portable::Platform,
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    /// The encodings of the changes last read for their inline inserts,
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    /// oldest first.
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    last_change: std::cell::RefCell<Vec<(ChangeHash, std::sync::Arc<Vec<u8>>)>>,
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    /// `--at-op`: read the repository as it was after this operation;
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    /// recording an operation is refused.
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    at_op: Option<ObjectRef>,
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}
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/// Marker file of a bare repository, inside `.oxy/`.
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const BARE_MARKER: &str = "bare";
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/// Marker of a hosted repository that has no id yet: the first push binds
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/// it to the pusher's id (spec §16.1).
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const UNBOUND_MARKER: &str = "unbound";
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/// The user's oxy directory: `$OXY_HOME`, else `$XDG_CONFIG_HOME/oxy`, else
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/// `~/.config/oxy`. It holds `config.toml` (spec §19) and `keys/`.
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pub fn default_home() -> PathBuf {
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    if let Ok(h) = std::env::var("OXY_HOME") {
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        return PathBuf::from(h);
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    }
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    if let Ok(x) = std::env::var("XDG_CONFIG_HOME") {
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        return PathBuf::from(x).join("oxy");
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    }
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    // Windows has no HOME as a rule: the roaming profile's application
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    // data, as Windows programs keep theirs.
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    #[cfg(windows)]
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    if let Some(d) = std::env::var_os("APPDATA").or_else(|| std::env::var_os("USERPROFILE")) {
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        return PathBuf::from(d).join("oxy");
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    }
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    let home = std::env::var("HOME").unwrap_or_else(|_| ".".into());
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    PathBuf::from(home).join(".config").join("oxy")
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}
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pub fn default_keys_dir() -> PathBuf {
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    default_home().join("keys")
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}
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pub fn default_user_config() -> PathBuf {
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    default_home().join("config.toml")
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}
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/// Where `create_identity` records the author.
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#[derive(Clone, Copy, Debug, PartialEq, Eq)]
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pub enum IdentityScope {
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    /// The user file: every repository of this user signs with it.
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    User,
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    /// This repository only.
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    Repo,
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}
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impl Repo {
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    // ------------------------------------------------------------ lifecycle
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    pub fn init(root: &Path) -> Result<Repo> {
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        let mut id = [0u8; 16];
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        rand::rngs::OsRng.fill_bytes(&mut id);
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        Self::init_with_id(root, id)
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    }
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    /// Initialize a repository with a given repository ID (clones share the
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    /// ID of their origin, spec §14.4).
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    pub fn init_with_id(root: &Path, id: [u8; 16]) -> Result<Repo> {
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        fs::create_dir_all(root)?;
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        let root = root.canonicalize().unwrap_or_else(|_| root.to_path_buf());
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        let oxy = root.join(OXY_DIR);
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        if oxy.exists() {
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            return fail(format!("{} is already an oxy repository", root.display()));
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        }
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        fs::create_dir_all(oxy.join("ops"))?;
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        write_atomic(&oxy.join("format"), FORMAT_LINE.as_bytes())?;
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        write_atomic(&oxy.join("id"), hex::encode(id).as_bytes())?;
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        let config = Config::load(Some(&default_user_config()), &oxy.join("config"))?;
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        config.save(&oxy.join("config"))?;
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        let workspace = WorkspaceId::random();
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        write_atomic(&oxy.join("workspace"), workspace.to_hex().as_bytes())?;
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        let store = Store::open(oxy.join("objects"))?;
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        let repo = Repo {
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            last_change: Default::default(),
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            at_op: None,
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            git_export_skipped: Default::default(),
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            manifest_cache: Default::default(),
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            listing_cache: Default::default(),
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            untracked_nested: Default::default(),
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            root,
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            oxy,
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            store,
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            workspace,
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            bare: false,
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            keys_dir: default_keys_dir(),
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            platform: crate::portable::Platform::current(),
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            user_config: default_user_config(),
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            config,
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        };
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        repo.register_workspace(&workspace, &repo.root)?;
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        let wc = repo.new_working_copy(vec![], "");
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        let wc_hash = repo.store.put_change(&wc)?;
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        let mut view = View::default();
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        view.bookmarks.insert(
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            repo.config.bookmark.clone(),
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            repo.store.put_state(&StateObject::new(vec![]))?,
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        );
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        view.workspaces.insert(workspace, wc_hash);
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        repo.record_op(&[], "oxy init", view)?;
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        Ok(repo)
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    }
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    /// Create a bare repository: an object store, operation log and
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    /// references with no workspace and no working copy, for hosting
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    /// (hub spec §4.1). `root` holds `.oxy/` and nothing else.
339 
    pub fn init_bare(root: &Path) -> Result<Repo> {
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        let mut id = [0u8; 16];
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        rand::rngs::OsRng.fill_bytes(&mut id);
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        Self::init_bare_with_id(root, id)
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    }
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    pub fn init_bare_with_id(root: &Path, id: [u8; 16]) -> Result<Repo> {
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        fs::create_dir_all(root)?;
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        let root = root.canonicalize().unwrap_or_else(|_| root.to_path_buf());
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        let oxy = root.join(OXY_DIR);
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        if oxy.exists() {
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            return fail(format!("{} is already an oxy repository", root.display()));
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        }
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        fs::create_dir_all(oxy.join("ops"))?;
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        write_atomic(&oxy.join("format"), FORMAT_LINE.as_bytes())?;
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        write_atomic(&oxy.join("id"), hex::encode(id).as_bytes())?;
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        write_atomic(&oxy.join(BARE_MARKER), b"")?;
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        let config = Config::load(Some(&default_user_config()), &oxy.join("config"))?;
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        config.save(&oxy.join("config"))?;
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        let store = Store::open(oxy.join("objects"))?;
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        let repo = Repo {
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            last_change: Default::default(),
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            at_op: None,
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            git_export_skipped: Default::default(),
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            manifest_cache: Default::default(),
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            listing_cache: Default::default(),
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            untracked_nested: Default::default(),
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            root,
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            oxy,
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            store,
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            workspace: WorkspaceId::ZERO,
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            bare: true,
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            keys_dir: default_keys_dir(),
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            platform: crate::portable::Platform::current(),
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            user_config: default_user_config(),
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            config,
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        };
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        let mut view = View::default();
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        view.bookmarks.insert(
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            repo.config.bookmark.clone(),
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            repo.store.put_state(&StateObject::new(vec![]))?,
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        );
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        repo.record_op(&[], "oxy init --bare", view)?;
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        Ok(repo)
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    }
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    /// A bare repository with no id yet. Its `id()` is all zero until the
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    /// first push binds it (`bind_id`), so an existing repository can be
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    /// pushed to a freshly created hosted one and keep its identity.
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    pub fn init_bare_unbound(root: &Path) -> Result<Repo> {
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        let repo = Self::init_bare_with_id(root, [0; 16])?;
390 
        fs::remove_file(repo.oxy.join("id"))?;
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        write_atomic(&repo.oxy.join(UNBOUND_MARKER), b"")?;
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        Ok(repo)
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    }
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    pub fn is_unbound(&self) -> bool {
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        self.oxy.join(UNBOUND_MARKER).is_file()
397 
    }
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    /// Give an unbound repository its id.
400 
    pub fn bind_id(&self, id: [u8; 16]) -> Result<()> {
401 
        if !self.is_unbound() {
402 
            return fail("this repository already has an id");
403 
        }
404 
        if id == [0; 16] {
405 
            return fail("a repository id cannot be all zero");
406 
        }
407 
        write_atomic(&self.oxy.join("id"), hex::encode(id).as_bytes())?;
408 
        fs::remove_file(self.oxy.join(UNBOUND_MARKER))?;
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        Ok(())
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    }
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    /// Whether this repository has no working copy (`init_bare`).
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    pub fn is_bare(&self) -> bool {
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        self.bare
415 
    }
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    /// Open the repository containing `start` (searching upwards).
418 
    pub fn open(start: &Path) -> Result<Repo> {
419 
        let start = start.canonicalize()?;
420 
        let mut dir: Option<&Path> = Some(&start);
421 
        while let Some(d) = dir {
422 
            let oxy = d.join(OXY_DIR);
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            if oxy.is_file() {
424 
                // A secondary workspace (spec §12.2): the file points at the repository.
425 
                let text = fs::read_to_string(&oxy)?;
426 
                let Some((shared, workspace)) = workspace::parse_workspace_file(&text) else {
427 
                    return fail(format!("{} is not a valid workspace file", oxy.display()));
428 
                };
429 
                let format = fs::read_to_string(shared.join("format"))?;
430 
                if format != FORMAT_LINE {
431 
                    return fail(format!("unsupported repository format: {}", format.trim()));
432 
                }
433 
                let config = Config::load(Some(&default_user_config()), &shared.join("config"))?;
434 
                let store = Store::open(shared.join("objects"))?;
75167672 Andy McCall 435 
                let mut repo = Repo {
519c7c06 Andy McCall ↶ 436 
                    last_change: Default::default(),
98a1620a Andy McCall ↶ 437 
                    at_op: None,
75167672 Andy McCall 438 
                    git_export_skipped: Default::default(),
d0990c2b Andy McCall ↶ 439 
                    manifest_cache: Default::default(),
76740263 Andy McCall ↶ 440 
                    listing_cache: Default::default(),
d4dbab97 Andy McCall ↶ 441 
                    untracked_nested: Default::default(),
75167672 Andy McCall 442 
                    root: d.to_path_buf(),
443 
                    oxy: shared,
444 
                    store,
445 
                    workspace,
446 
                    bare: false,
447 
                    keys_dir: default_keys_dir(),
c863c7a7 Andy McCall ↶ 448 
                    platform: crate::portable::Platform::current(),
75167672 Andy McCall 449 
                    user_config: default_user_config(),
450 
                    config,
451 
                };
7b9809e6 Andy McCall ↶ 452 
                repo.apply_workspace_bookmark();
453 
                return Ok(repo);
4e88e774 Andy McCall ↶ 454 
            }
98286406 Andy McCall ↶ 455 
            if oxy.is_dir() {
456 
                let format = fs::read_to_string(oxy.join("format"))?;
457 
                let config = Config::load(Some(&default_user_config()), &oxy.join("config"))?;
e02bf0cd Andy McCall ↶ 458 
                let bare = oxy.join(BARE_MARKER).is_file();
459 
                let workspace = if bare {
460 
                    WorkspaceId::ZERO
461 
                } else {
75167672 Andy McCall 462 
                    WorkspaceId::from_hex(fs::read_to_string(oxy.join("workspace"))?.trim())
463 
                        .ok_or_else(|| RepoError::Msg("corrupt .oxy/workspace".into()))?
e02bf0cd Andy McCall ↶ 464 
                };
98286406 Andy McCall ↶ 465 
                let store = Store::open(oxy.join("objects"))?;
75167672 Andy McCall 466 
                let mut repo = Repo {
519c7c06 Andy McCall ↶ 467 
                    last_change: Default::default(),
98a1620a Andy McCall ↶ 468 
                    at_op: None,
75167672 Andy McCall 469 
                    git_export_skipped: Default::default(),
d0990c2b Andy McCall ↶ 470 
                    manifest_cache: Default::default(),
76740263 Andy McCall ↶ 471 
                    listing_cache: Default::default(),
d4dbab97 Andy McCall ↶ 472 
                    untracked_nested: Default::default(),
75167672 Andy McCall 473 
                    root: d.to_path_buf(),
474 
                    oxy,
475 
                    store,
476 
                    workspace,
477 
                    bare,
478 
                    keys_dir: default_keys_dir(),
c863c7a7 Andy McCall ↶ 479 
                    platform: crate::portable::Platform::current(),
75167672 Andy McCall 480 
                    user_config: default_user_config(),
481 
                    config,
482 
                };
e02bf0cd Andy McCall ↶ 483 
                if !bare {
484 
                    repo.apply_workspace_bookmark();
485 
                }
98286406 Andy McCall ↶ 486 
                if format == FORMAT1_LINE {
487 
                    repo.migrate_format1()?;
488 
                } else if format != FORMAT_LINE {
489 
                    return fail(format!("unsupported repository format: {}", format.trim()));
490 
                }
491 
                return Ok(repo);
492 
            }
493 
            dir = d.parent();
494 
        }
75167672 Andy McCall 495 
        fail(format!(
3e5772cc Andy McCall ↶ 496 
            "no oxy repository found at or above {}; start one with `oxy init` or `oxy clone URL`",
75167672 Andy McCall 497 
            start.display()
498 
        ))
98286406 Andy McCall ↶ 499 
    }
500
501 
    /// Rewrite a format-1 operation log, whose bookmarks were head lists,
502 
    /// into format 2, where each bookmark names a `state` object.
503 
    fn migrate_format1(&self) -> Result<()> {
504 
        let hex = fs::read_to_string(self.oxy.join("ops").join("head"))?;
75167672 Andy McCall 505 
        let head = ObjectRef::from_hex(hex.trim())
506 
            .ok_or_else(|| RepoError::Msg("corrupt .oxy/ops/head".into()))?;
98286406 Andy McCall ↶ 507 
        // Collect the chain root-first.
508 
        let mut chain: Vec<Format1Op> = Vec::new();
509 
        let mut cur = Some(head);
510 
        while let Some(r) = cur {
511 
            let op = Op::decode_format1(&self.store.get_typed(&r, ObjectType::Op)?)?;
512 
            cur = op.parents.first().copied();
513 
            chain.push(op);
514 
        }
515 
        chain.reverse();
516 
        let mut new_parent: Option<ObjectRef> = None;
517 
        for old in chain {
518 
            let mut view = View::default();
519 
            for (name, heads) in &old.view.bookmarks {
75167672 Andy McCall 520 
                view.bookmarks.insert(
521 
                    name.clone(),
522 
                    self.store.put_state(&StateObject::new(heads.clone()))?,
523 
                );
98286406 Andy McCall ↶ 524 
            }
525 
            view.workspaces = old.view.workspaces.clone();
75167672 Andy McCall 526 
            let op = Op {
527 
                parents: new_parent.into_iter().collect(),
528 
                hlc: old.hlc,
529 
                command: old.command,
530 
                view,
531 
            };
98286406 Andy McCall ↶ 532 
            new_parent = Some(self.store.put(ObjectType::Op, &op.encode())?);
533 
        }
75167672 Andy McCall 534 
        write_atomic(
535 
            &self.oxy.join("ops").join("head"),
536 
            new_parent.unwrap().to_hex().as_bytes(),
537 
        )?;
98286406 Andy McCall ↶ 538 
        write_atomic(&self.oxy.join("format"), FORMAT_LINE.as_bytes())?;
539 
        Ok(())
d02e545d Andy McCall ↶ 540 
    }
541
542 
    /// Pack automatically once many loose objects have accumulated.
543 
    pub(crate) fn maybe_autopack(&self) -> Result<()> {
544 
        if self.store.loose_count()? > AUTOPACK_THRESHOLD {
545 
            self.store.pack_loose()?;
135212de Andy McCall ↶ 546 
            self.store.merge_packs()?;
d02e545d Andy McCall ↶ 547 
        }
548 
        Ok(())
549 
    }
550
98286406 Andy McCall ↶ 551 
    /// The repository ID (spec §14.4). Repositories made before IDs existed get one on first use.
552 
    pub fn id(&self) -> Result<[u8; 16]> {
75167672 Andy McCall 553 
        if self.is_unbound() {
554 
            return Ok([0; 16]);
555 
        }
98286406 Andy McCall ↶ 556 
        let path = self.oxy.join("id");
557 
        match fs::read_to_string(&path) {
75167672 Andy McCall 558 
            Ok(h) => hex::decode(h.trim())
559 
                .ok()
560 
                .and_then(|v| v.try_into().ok())
561 
                .ok_or_else(|| RepoError::Msg("corrupt .oxy/id".into())),
98286406 Andy McCall ↶ 562 
            Err(e) if e.kind() == std::io::ErrorKind::NotFound => {
563 
                let mut id = [0u8; 16];
564 
                rand::rngs::OsRng.fill_bytes(&mut id);
565 
                write_atomic(&path, hex::encode(id).as_bytes())?;
566 
                Ok(id)
567 
            }
568 
            Err(e) => Err(e.into()),
569 
        }
570 
    }
571
572 
    pub fn root(&self) -> &Path {
573 
        &self.root
574 
    }
575 
    pub fn store(&self) -> &Store {
576 
        &self.store
577 
    }
578 
    pub fn workspace(&self) -> WorkspaceId {
579 
        self.workspace
580 
    }
581
582 
    /// Use a different user directory for keys and the user config file
583 
    /// (tests, or `$OXY_HOME`). Reloads the effective configuration.
c863c7a7 Andy McCall ↶ 584 
    /// Act as if the working copy were on another platform's file system
585 
    /// (tests of Windows and macOS behaviour on any host).
586 
    pub fn with_platform(mut self, platform: crate::portable::Platform) -> Repo {
587 
        self.platform = platform;
588 
        self
589 
    }
590
591 
    pub fn platform(&self) -> crate::portable::Platform {
592 
        self.platform
593 
    }
594
98286406 Andy McCall ↶ 595 
    pub fn with_home(mut self, dir: impl Into<PathBuf>) -> Repo {
596 
        let dir = dir.into();
597 
        self.keys_dir = dir.join("keys");
598 
        self.user_config = dir.join("config.toml");
599 
        if let Ok(c) = Config::load(Some(&self.user_config), &self.oxy.join("config")) {
600 
            self.config = c;
601 
        }
7b9809e6 Andy McCall ↶ 602 
        self.apply_workspace_bookmark();
98286406 Andy McCall ↶ 603 
        self
604 
    }
605
7b9809e6 Andy McCall ↶ 606 
    /// The workspace's current bookmark (spec §10.1) overrides the
607 
    /// configured default when `oxy bookmark switch` has recorded one.
608 
    fn apply_workspace_bookmark(&mut self) {
75167672 Andy McCall 609 
        if let Ok(b) = fs::read_to_string(
610 
            self.oxy
611 
                .join("workspaces")
612 
                .join(self.workspace.to_hex())
613 
                .join("bookmark"),
614 
        ) {
7b9809e6 Andy McCall ↶ 615 
            let b = b.trim();
616 
            if !b.is_empty() {
617 
                self.config.bookmark = b.to_string();
618 
            }
619 
        }
620 
    }
621
98286406 Andy McCall ↶ 622 
    pub fn user_config_path(&self) -> &Path {
623 
        &self.user_config
624 
    }
625
626 
    /// Set a key in the user file and refresh the effective configuration.
627 
    pub fn set_user_config(&mut self, key: &str, value: &str) -> Result<()> {
628 
        Config::set_user(&self.user_config, key, value)?;
629 
        self.config = Config::load(Some(&self.user_config), &self.oxy.join("config"))?;
630 
        Ok(())
631 
    }
632
633 
    pub fn save_config(&self) -> Result<()> {
634 
        self.config.save(&self.oxy.join("config"))
635 
    }
636
637 
    fn author(&self) -> KeyId {
638 
        self.config.author_key.unwrap_or(ObjectRef::ZERO)
639 
    }
640 
}
641
642 
impl Repo {
643 
    fn new_working_copy(&self, deps: Vec<ChangeHash>, message: &str) -> Change {
644 
        let mut c = Change {
6f8aeb99 Andy McCall ↶ 645 
            version: crate::objects::CHANGE_VERSION,
98286406 Andy McCall ↶ 646 
            change_id: ChangeId::random(),
647 
            deps,
648 
            author: self.author(),
649 
            hlc: Hlc::now(),
650 
            message: message.into(),
651 
            tree_ops: vec![],
652 
            edits: vec![],
653 
            kind: ChangeKind::WorkingCopy,
654 
        };
655 
        c.normalize();
656 
        c
657 
    }
658
659 
    // ------------------------------------------------------------ operation log
660
661 
    pub fn head_op(&self) -> Result<(ObjectRef, Op)> {
98a1620a Andy McCall ↶ 662 
        if let Some(r) = self.at_op {
663 
            return Ok((r, Op::decode(&self.store.get_typed(&r, ObjectType::Op)?)?));
664 
        }
98286406 Andy McCall ↶ 665 
        let hex = fs::read_to_string(self.oxy.join("ops").join("head"))?;
75167672 Andy McCall 666 
        let r = ObjectRef::from_hex(hex.trim())
667 
            .ok_or_else(|| RepoError::Msg("corrupt .oxy/ops/head".into()))?;
98286406 Andy McCall ↶ 668 
        let op = Op::decode(&self.store.get_typed(&r, ObjectType::Op)?)?;
669 
        Ok((r, op))
670 
    }
671
672 
    pub fn view(&self) -> Result<View> {
673 
        Ok(self.head_op()?.1.view)
674 
    }
675
676 
    fn record_op(&self, parents: &[ObjectRef], command: &str, view: View) -> Result<ObjectRef> {
98a1620a Andy McCall ↶ 677 
        if self.at_op.is_some() {
678 
            return fail(
679 
                "--at-op shows the repository as it was; this command would change it (run it without --at-op)",
680 
            );
681 
        }
75167672 Andy McCall 682 
        let op = Op {
683 
            parents: parents.to_vec(),
684 
            hlc: Hlc::now(),
685 
            command: command.into(),
686 
            view,
687 
        };
98286406 Andy McCall ↶ 688 
        let r = self.store.put(ObjectType::Op, &op.encode())?;
4dcb8c09 Andy McCall ↶ 689 
        // The head is the commit point: everything it names must be on disk first.
690 
        self.store.flush()?;
19555025 Andy McCall ↶ 691 
        // Compare and swap under a short lock (spec §12.1): when another
692 
        // process recorded an operation since this one read the head, the
693 
        // two are merged instead of one overwriting the other.
694 
        let _lock = self.lock_ops()?;
695 
        let current = match parents.first() {
696 
            // The first operation (init): there is no head yet.
697 
            None => None,
698 
            Some(_) => Some(self.head_ref()?),
699 
        };
700 
        let Some(current) = current.filter(|c| Some(c) != parents.first()) else {
701 
            write_atomic(&self.oxy.join("ops").join("head"), r.to_hex().as_bytes())?;
702 
            return Ok(r);
703 
        };
704 
        let base = match parents.first() {
705 
            Some(p) => Op::decode(&self.store.get_typed(p, ObjectType::Op)?)?.view,
706 
            None => View::default(),
707 
        };
708 
        let theirs = Op::decode(&self.store.get_typed(&current, ObjectType::Op)?)?.view;
709 
        let merged = Op {
710 
            parents: vec![current, r],
711 
            hlc: Hlc::now(),
712 
            command: format!("{command} (merged with a concurrent operation)"),
713 
            view: self.merge_views(&base, &op.view, &theirs)?,
714 
        };
715 
        let m = self.store.put(ObjectType::Op, &merged.encode())?;
716 
        self.store.flush()?;
717 
        write_atomic(&self.oxy.join("ops").join("head"), m.to_hex().as_bytes())?;
718 
        Ok(m)
719 
    }
720
721 
    /// The operation head's lock, held only while the head pointer moves.
722 
    fn lock_ops(&self) -> Result<FileLock> {
723 
        fs::create_dir_all(self.oxy.join("ops"))?;
724 
        FileLock::acquire(
725 
            self.oxy.join("ops").join("lock"),
726 
            "another oxy process holds the operation log",
727 
        )
728 
    }
729
730 
    fn head_ref(&self) -> Result<ObjectRef> {
731 
        let hex = fs::read_to_string(self.oxy.join("ops").join("head"))?;
732 
        ObjectRef::from_hex(hex.trim())
733 
            .ok_or_else(|| RepoError::Msg("corrupt .oxy/ops/head".into()))
734 
    }
735
736 
    /// Three-way merge of two views that both started from `base` (spec
737 
    /// §12.1). A reference only one side changed takes that side's value.
738 
    /// When both changed it differently: a bookmark keeps both sides'
6caacfff Andy McCall ↶ 739 
    /// heads (it may then have several), a change beats a deletion, a
740 
    /// workspace changed by both is an error (only one of them matches the
741 
    /// files on disk), and otherwise this process's value wins for remote
19555025 Andy McCall ↶ 742 
    /// references and the policy, the first value for a tag (tags never
743 
    /// move).
744 
    fn merge_views(&self, base: &View, ours: &View, theirs: &View) -> Result<View> {
745 
        fn pick<K: Ord + Clone, V: Clone + PartialEq>(
746 
            b: &BTreeMap<K, V>,
747 
            o: &BTreeMap<K, V>,
748 
            t: &BTreeMap<K, V>,
749 
            mut both: impl FnMut(&V, &V) -> Result<V>,
750 
        ) -> Result<BTreeMap<K, V>> {
751 
            let keys: BTreeSet<&K> = b.keys().chain(o.keys()).chain(t.keys()).collect();
752 
            let mut out = BTreeMap::new();
753 
            for k in keys {
754 
                let (bv, ov, tv) = (b.get(k), o.get(k), t.get(k));
755 
                let v = if ov == tv || tv == bv {
756 
                    ov.cloned()
757 
                } else if ov == bv {
758 
                    tv.cloned()
759 
                } else {
760 
                    match (ov, tv) {
761 
                        (Some(x), Some(y)) => Some(both(x, y)?),
762 
                        (Some(x), None) | (None, Some(x)) => Some(x.clone()),
763 
                        (None, None) => None,
764 
                    }
765 
                };
766 
                if let Some(v) = v {
767 
                    out.insert(k.clone(), v);
768 
                }
769 
            }
770 
            Ok(out)
771 
        }
772 
        let bookmarks = pick(
773 
            &base.bookmarks,
774 
            &ours.bookmarks,
775 
            &theirs.bookmarks,
776 
            |x, y| {
777 
                let mut heads = self.store.get_state(x)?.heads;
778 
                heads.extend(self.store.get_state(y)?.heads);
779 
                let heads = self.load_state(&heads)?.maximal(&heads);
780 
                Ok(self.store.put_state(&StateObject::new(heads))?)
781 
            },
782 
        )?;
6caacfff Andy McCall ↶ 783 
        // Two operations that both replaced one workspace's working copy
784 
        // cannot both be right: the files on disk match only one of them.
785 
        // The working-copy lock keeps this from happening; should it happen
786 
        // anyway, this operation is not recorded.
19555025 Andy McCall ↶ 787 
        let workspaces = pick(
788 
            &base.workspaces,
789 
            &ours.workspaces,
790 
            &theirs.workspaces,
6caacfff Andy McCall ↶ 791 
            |_, _| {
792 
                fail(
793 
                    "another oxy process changed this working copy at the same time; \
794 
                     this command was not recorded: check `oxy status` and run it again",
795 
                )
796 
            },
19555025 Andy McCall ↶ 797 
        )?;
798 
        let tags = pick(&base.tags, &ours.tags, &theirs.tags, |_, y| Ok(*y))?;
799 
        let empty = BTreeMap::new();
800 
        let names: BTreeSet<&String> = base
801 
            .remotes
802 
            .keys()
803 
            .chain(ours.remotes.keys())
804 
            .chain(theirs.remotes.keys())
805 
            .collect();
806 
        let mut remotes = BTreeMap::new();
807 
        for n in names {
808 
            let m = pick(
809 
                base.remotes.get(n).unwrap_or(&empty),
810 
                ours.remotes.get(n).unwrap_or(&empty),
811 
                theirs.remotes.get(n).unwrap_or(&empty),
812 
                |x, _| Ok(*x),
813 
            )?;
814 
            if !m.is_empty() {
815 
                remotes.insert(n.clone(), m);
816 
            }
817 
        }
818 
        let policy = if ours.policy == theirs.policy || theirs.policy == base.policy {
819 
            ours.policy
820 
        } else if ours.policy == base.policy {
821 
            theirs.policy
822 
        } else {
823 
            ours.policy.or(theirs.policy)
824 
        };
825 
        self.store.flush()?;
826 
        Ok(View {
827 
            bookmarks,
828 
            workspaces,
829 
            remotes,
830 
            policy,
831 
            tags,
832 
        })
98286406 Andy McCall ↶ 833 
    }
834
835 
    pub fn op_log(&self) -> Result<Vec<(ObjectRef, Op)>> {
836 
        let mut out = Vec::new();
837 
        let (mut r, mut op) = self.head_op()?;
838 
        loop {
839 
            let next = op.parents.first().copied();
840 
            out.push((r, op));
841 
            match next {
842 
                Some(p) => {
843 
                    r = p;
844 
                    op = Op::decode(&self.store.get_typed(&r, ObjectType::Op)?)?;
845 
                }
846 
                None => break,
847 
            }
848 
        }
849 
        Ok(out)
850 
    }
851
852 
    /// Undo the last user command (spec §12.1). Operations that only recorded
853 
    /// a working-copy snapshot are skipped, since the files are still on disk
98a1620a Andy McCall ↶ 854 
    /// and the next snapshot recreates them, and a command's own checkout
855 
    /// (`… (checkout)`) goes with the command. When the working copy is
856 
    /// clean and was clean after the operation undone to, its files follow
857 
    /// too, since nothing on disk can be lost; otherwise they stay as they
858 
    /// are (an undone commit's edits come back as uncommitted work).
98286406 Andy McCall ↶ 859 
    pub fn undo(&self) -> Result<Op> {
6caacfff Andy McCall ↶ 860 
        let _wc = self.lock_working_copy()?;
98a1620a Andy McCall ↶ 861 
        let clean_now =
862 
            self.clean_by_manifest()? || self.snapshot_status("oxy undo")?.statuses.is_empty();
19555025 Andy McCall ↶ 863 
        let (read_head, mut op) = self.head_op()?;
98a1620a Andy McCall ↶ 864 
        let wc_now = op.view.workspaces.get(&self.workspace).copied();
865 
        let up = |op: Op| -> Result<Option<Op>> {
866 
            match op.parents.first() {
867 
                Some(p) => Ok(Some(Op::decode(&self.store.get_typed(p, ObjectType::Op)?)?)),
868 
                None => Ok(None),
869 
            }
870 
        };
871 
        loop {
872 
            while op.is_snapshot() {
873 
                match up(op.clone())? {
874 
                    Some(p) => op = p,
875 
                    None => break,
876 
                }
877 
            }
878 
            if !op.command.ends_with(" (checkout)") {
75167672 Andy McCall 879 
                break;
98a1620a Andy McCall ↶ 880 
            }
881 
            match up(op.clone())? {
882 
                Some(p) => op = p,
883 
                None => break,
884 
            }
98286406 Andy McCall ↶ 885 
        }
886 
        let Some(parent) = op.parents.first() else {
887 
            return fail("nothing to undo");
888 
        };
889 
        let parent_op = Op::decode(&self.store.get_typed(parent, ObjectType::Op)?)?;
98a1620a Andy McCall ↶ 890 
        {
891 
            let _lock = self.lock_ops()?;
892 
            if self.head_ref()? != read_head {
893 
                return fail("another oxy command ran while undoing; run undo again");
894 
            }
895 
            write_atomic(
896 
                &self.oxy.join("ops").join("head"),
897 
                parent.to_hex().as_bytes(),
898 
            )?;
19555025 Andy McCall ↶ 899 
        }
135212de Andy McCall ↶ 900 
        self.drop_manifest();
98a1620a Andy McCall ↶ 901 
        if let Some(then) = parent_op.view.workspaces.get(&self.workspace) {
902 
            if clean_now && Some(*then) != wc_now {
903 
                let wc = self.store.get_change(then)?;
904 
                if wc.edits.is_empty() && wc.tree_ops.is_empty() {
905 
                    let base = self.load_state_history(&wc.deps)?.maximal(&wc.deps);
906 
                    // The files differ from the restored working copy by
907 
                    // exactly what the undone command did: nothing else is
908 
                    // on disk, as the working copy was clean.
909 
                    self.checkout(&base, true, "oxy undo (checkout)")?;
910 
                }
911 
            }
912 
        }
98286406 Andy McCall ↶ 913 
        Ok(parent_op)
914 
    }
915
916 
    /// The last operation that was not a snapshot.
917 
    pub fn last_command(&self) -> Result<Op> {
918 
        let (_, mut op) = self.head_op()?;
919 
        while op.is_snapshot() {
75167672 Andy McCall 920 
            let Some(parent) = op.parents.first() else {
921 
                break;
922 
            };
98286406 Andy McCall ↶ 923 
            op = Op::decode(&self.store.get_typed(parent, ObjectType::Op)?)?;
924 
        }
925 
        Ok(op)
926 
    }
927
928 
    // ------------------------------------------------------------ states
929
252e8cb2 Andy McCall ↶ 930 
    /// Load the dependency closure of `heads`, through a checkpoint when one applies.
98286406 Andy McCall ↶ 931 
    pub fn load_state(&self, heads: &[ChangeHash]) -> Result<State> {
252e8cb2 Andy McCall ↶ 932 
        if let Some(st) = self.load_state_checkpointed(heads)? {
933 
            return Ok(st);
934 
        }
935 
        self.load_state_full(heads)
936 
    }
937
e8d38e47 Andy McCall ↶ 938 
    /// The state of `heads` for its history (changes, tree, metadata) with
939 
    /// no file graph built: much cheaper than [`Repo::load_state`] for log
940 
    /// and friends. Build the graphs a command needs with
941 
    /// [`Repo::load_graphs_of`].
942 
    pub fn load_state_history(&self, heads: &[ChangeHash]) -> Result<State> {
943 
        if let Some(st) = self.load_state_checkpointed_as(heads, true)? {
944 
            return Ok(st);
945 
        }
946 
        self.load_state_replayed(heads, State::new_history_only())
947 
    }
948
949 
    /// Build these file graphs in a history-only state.
950 
    pub fn load_graphs_of(&self, state: &mut State, nodes: &[crate::ids::NodeId]) -> Result<()> {
a4fad5b0 Andy McCall ↶ 951 
        Ok(state.load_graphs(
952 
            nodes,
953 
            |refs| {
954 
                self.read_blobs(refs).map_err(|e| {
955 
                    crate::objects::ObjectError::Schema(format!("graph and text blobs: {e}"))
956 
                })
957 
            },
958 
            |h| self.change_bytes(h),
959 
        )?)
cc7a0056 Andy McCall ↶ 960 
    }
961
57d8dc05 Andy McCall ↶ 962 
    /// The graphs of `nodes` of a history-only state, built beside it (see
963 
    /// [`State::build_graphs_detached`]).
964 
    pub fn build_graphs_detached(
965 
        &self,
966 
        state: &State,
967 
        nodes: &[crate::ids::NodeId],
968 
    ) -> Result<HashMap<crate::ids::NodeId, crate::graph::FileGraph>> {
969 
        Ok(state
970 
            .build_graphs_detached(
971 
                nodes,
972 
                |refs| {
973 
                    self.read_blobs(refs).map_err(|e| {
974 
                        crate::objects::ObjectError::Schema(format!("graph and text blobs: {e}"))
975 
                    })
976 
                },
977 
                |h| self.change_bytes(h),
978 
            )?
979 
            .into_iter()
980 
            .collect())
981 
    }
982
091fef80 Andy McCall ↶ 983 
    /// The contents of texts [`State::single_text`] gave: blobs read in
984 
    /// one go, inline ones from their changes.
11e2b98a Andy McCall ↶ 985 
    pub fn single_texts(&self, texts: &[crate::objects::TextRef]) -> Result<Vec<Vec<u8>>> {
091fef80 Andy McCall ↶ 986 
        use crate::objects::TextRef;
987 
        let refs: Vec<ObjectRef> = texts
988 
            .iter()
989 
            .filter_map(|t| match t {
990 
                TextRef::Blob(r, _, _) => Some(*r),
991 
                TextRef::Inline { .. } => None,
992 
            })
993 
            .collect();
994 
        let mut blobs = self.read_blobs(&refs)?.into_iter();
995 
        let mut out = Vec::with_capacity(texts.len());
996 
        for t in texts {
997 
            let lines = match t {
998 
                TextRef::Blob(_, count, form) => {
999 
                    let content = blobs
1000 
                        .next()
1001 
                        .ok_or_else(|| RepoError::Msg("text blobs: wrong count".into()))?;
1002 
                    crate::objects::text_lines(&content, *count, *form)?
1003 
                }
1004 
                TextRef::Inline { change, start, end } => {
1005 
                    let bytes = self.change_bytes(change)?;
1006 
                    let range = bytes.get(*start as usize..*end as usize).ok_or_else(|| {
1007 
                        RepoError::Msg("an inline insert lies outside its change".into())
1008 
                    })?;
1009 
                    crate::objects::inline_lines(range)?
1010 
                }
1011 
            };
1012 
            out.push(lines.bytes().to_vec());
1013 
        }
1014 
        Ok(out)
1015 
    }
1016
cc7a0056 Andy McCall ↶ 1017 
    /// Build every graph a history-only state still lacks, making it full.
1018 
    pub fn load_all_graphs(&self, state: &mut State) -> Result<()> {
a4fad5b0 Andy McCall ↶ 1019 
        Ok(state.load_all_graphs(
1020 
            |refs| {
1021 
                self.read_blobs(refs).map_err(|e| {
1022 
                    crate::objects::ObjectError::Schema(format!("graph and text blobs: {e}"))
1023 
                })
1024 
            },
1025 
            |h| self.change_bytes(h),
1026 
        )?)
1027 
    }
1028
519c7c06 Andy McCall ↶ 1029 
    /// A change's encoding, for building graphs of its inline inserts. The
acadb5ed Andy McCall ↶ 1030 
    /// last few read are kept: a checkout building graphs a batch at a
1031 
    /// time reads the same large changes for every batch, often in turn.
a4fad5b0 Andy McCall ↶ 1032 
    fn change_bytes(
1033 
        &self,
1034 
        h: &ChangeHash,
519c7c06 Andy McCall ↶ 1035 
    ) -> std::result::Result<std::sync::Arc<Vec<u8>>, crate::objects::ObjectError> {
acadb5ed Andy McCall ↶ 1036 
        let mut cache = self.last_change.borrow_mut();
1037 
        if let Some(i) = cache.iter().position(|(k, _)| k == h) {
1038 
            let hit = cache.remove(i);
1039 
            let b = hit.1.clone();
1040 
            cache.push(hit);
1041 
            return Ok(b);
519c7c06 Andy McCall ↶ 1042 
        }
1043 
        let b = std::sync::Arc::new(self.store.get_typed(h, ObjectType::Change).map_err(|e| {
a4fad5b0 Andy McCall ↶ 1044 
            crate::objects::ObjectError::Schema(format!("change {}: {e}", h.short(12)))
519c7c06 Andy McCall ↶ 1045 
        })?);
acadb5ed Andy McCall ↶ 1046 
        cache.push((*h, b.clone()));
1047 
        // The last few, within a memory budget; the newest always stays.
1048 
        while cache.len() > CHANGE_CACHE_COUNT
1049 
            || (cache.len() > 1
1050 
                && cache.iter().map(|(_, b)| b.len()).sum::<usize>() > CHANGE_CACHE_BYTES)
1051 
        {
1052 
            cache.remove(0);
1053 
        }
519c7c06 Andy McCall ↶ 1054 
        Ok(b)
e8d38e47 Andy McCall ↶ 1055 
    }
1056
252e8cb2 Andy McCall ↶ 1057 
    /// Load the dependency closure of `heads` change by change.
1058 
    pub fn load_state_full(&self, heads: &[ChangeHash]) -> Result<State> {
e8d38e47 Andy McCall ↶ 1059 
        self.load_state_replayed(heads, State::new())
1060 
    }
1061
1062 
    fn load_state_replayed(&self, heads: &[ChangeHash], mut state: State) -> Result<State> {
86e1824f Andy McCall ↶ 1063 
        let history = state.is_history_only();
98286406 Andy McCall ↶ 1064 
        let mut stack: Vec<ChangeHash> = heads.to_vec();
1065 
        let mut seen: BTreeSet<ChangeHash> = BTreeSet::new();
0bdc3f91 Andy McCall ↶ 1066 
        {
1067 
            let _t = crate::timing::phase("load: read and add changes");
d0d52107 Andy McCall ↶ 1068 
            let (mut read, mut add, mut fetch) = (
1069 
                std::time::Duration::ZERO,
1070 
                std::time::Duration::ZERO,
1071 
                std::time::Duration::ZERO,
1072 
            );
0bdc3f91 Andy McCall ↶ 1073 
            while let Some(h) = stack.pop() {
f9466021 Andy McCall ↶ 1074 
                // A change the state holds brings its history with it.
1075 
                if !seen.insert(h) || state.contains(&h) {
0bdc3f91 Andy McCall ↶ 1076 
                    continue;
1077 
                }
1078 
                let t0 = std::time::Instant::now();
86e1824f Andy McCall ↶ 1079 
                // A history-only state reads text only for the graphs it
1080 
                // builds; either way the hash is the one asked for.
1081 
                let (c, texts) = if history {
d0d52107 Andy McCall ↶ 1082 
                    let bytes = self.store.get_typed(&h, ObjectType::Change)?;
1083 
                    fetch += t0.elapsed();
1084 
                    Change::decode_skeleton(&bytes, h)
1085 
                        .map_err(|e| crate::store::StoreError::Corrupt(h, e.to_string()))?
86e1824f Andy McCall ↶ 1086 
                } else {
1087 
                    (self.store.get_change(&h)?, Vec::new())
1088 
                };
0bdc3f91 Andy McCall ↶ 1089 
                read += t0.elapsed();
1090 
                stack.extend(c.deps.iter().copied());
1091 
                let t1 = std::time::Instant::now();
86e1824f Andy McCall ↶ 1092 
                state.add_known(h, c, texts);
0bdc3f91 Andy McCall ↶ 1093 
                add += t1.elapsed();
98286406 Andy McCall ↶ 1094 
            }
0bdc3f91 Andy McCall ↶ 1095 
            crate::timing::record("load:   of which reading", read);
d0d52107 Andy McCall ↶ 1096 
            crate::timing::record("load:     of which fetching", fetch);
0bdc3f91 Andy McCall ↶ 1097 
            crate::timing::record("load:   of which applying", add);
98286406 Andy McCall ↶ 1098 
        }
0bdc3f91 Andy McCall ↶ 1099 
        let _t = crate::timing::phase("load: validate");
98286406 Andy McCall ↶ 1100 
        state.validate()?;
1101 
        Ok(state)
1102 
    }
1103
1104 
    pub fn working_copy(&self) -> Result<(ChangeHash, Change)> {
e02bf0cd Andy McCall ↶ 1105 
        if self.bare {
1106 
            return fail("this is a bare repository: it has no working copy");
1107 
        }
98286406 Andy McCall ↶ 1108 
        let view = self.view()?;
1109 
        let h = *view
1110 
            .workspaces
1111 
            .get(&self.workspace)
1112 
            .ok_or_else(|| RepoError::Msg("this workspace is not in the current view".into()))?;
1113 
        Ok((h, self.store.get_change(&h)?))
1114 
    }
1115
1116 
    /// Heads of a bookmark's state (spec §10.1).
1117 
    pub fn heads_of(&self, view: &View, bookmark: &str) -> Result<Vec<ChangeHash>> {
1118 
        match view.bookmarks.get(bookmark) {
1119 
            Some(st) => Ok(self.store.get_state(st)?.heads),
1120 
            None => Ok(vec![]),
1121 
        }
1122 
    }
1123
1124 
    pub fn bookmark_heads(&self) -> Result<Vec<ChangeHash>> {
1125 
        self.heads_of(&self.view()?, &self.config.bookmark)
1126 
    }
1127
1128 
    // ------------------------------------------------------------ blobs
1129
1130 
    fn blob_for(content: &[u8]) -> Blob {
6f8aeb99 Andy McCall ↶ 1131 
        Blob::of(content)
98286406 Andy McCall ↶ 1132 
    }
1133
1134 
    pub fn blob_ref(content: &[u8]) -> ObjectRef {
1135 
        Self::blob_for(content).hash()
1136 
    }
1137
1138 
    pub fn store_blob(&self, content: &[u8]) -> Result<ObjectRef> {
1139 
        for c in crate::chunk::chunks(content) {
1140 
            self.store.put_chunk(c)?;
1141 
        }
75167672 Andy McCall 1142 
        Ok(self
1143 
            .store
1144 
            .put(ObjectType::Blob, &Self::blob_for(content).encode())?)
98286406 Andy McCall ↶ 1145 
    }
1146
afaba5f1 Andy McCall ↶ 1147 
    /// Read many blobs at once (checkpoint graphs): the blob objects, then
1148 
    /// all their chunks, are read in parallel; a blob the store lacks goes
1149 
    /// through [`Repo::read_blob`], which may fetch it lazily.
1150 
    pub fn read_blobs(&self, refs: &[ObjectRef]) -> Result<Vec<Vec<u8>>> {
1151 
        let mut blobs: Vec<Option<Blob>> = Vec::with_capacity(refs.len());
1152 
        for (r, got) in refs.iter().zip(self.store.get_many(refs)) {
1153 
            blobs.push(match got {
1154 
                Ok((ObjectType::Blob, body)) => Some(Blob::decode(&body)?),
1155 
                Ok((ty, _)) => return fail(format!("{} is a {ty:?}, not a blob", r.short(12))),
1156 
                Err(crate::store::StoreError::NotFound(_)) => None,
1157 
                Err(e) => return Err(e.into()),
1158 
            });
1159 
        }
1160 
        let chunk_refs: Vec<ObjectRef> = blobs
1161 
            .iter()
1162 
            .flatten()
1163 
            .flat_map(|b| b.chunks.iter().copied())
1164 
            .collect();
1165 
        let mut chunks = self.store.get_many(&chunk_refs).into_iter();
1166 
        let mut out = Vec::with_capacity(refs.len());
1167 
        for (r, blob) in refs.iter().zip(blobs) {
1168 
            match blob {
1169 
                None => out.push(self.read_blob(r)?),
1170 
                Some(b) => {
1171 
                    let mut content = Vec::with_capacity(b.length as usize);
1172 
                    for c in &b.chunks {
1173 
                        match chunks.next() {
1174 
                            Some(Ok((ObjectType::Chunk, body))) => content.extend(body),
1175 
                            Some(Ok(_)) => return fail(format!("{} is not a chunk", c.short(12))),
1176 
                            Some(Err(e)) => return Err(e.into()),
1177 
                            None => return fail("chunk list ended early"),
1178 
                        }
1179 
                    }
1180 
                    out.push(content);
1181 
                }
1182 
            }
1183 
        }
1184 
        Ok(out)
1185 
    }
1186
b3c5a59a Andy McCall ↶ 1187 
    /// Read a blob's content, fetching it from the remote that withheld it
1188 
    /// when it is lazily absent (spec §13.5).
98286406 Andy McCall ↶ 1189 
    pub fn read_blob(&self, r: &ObjectRef) -> Result<Vec<u8>> {
b3c5a59a Andy McCall ↶ 1190 
        if !self.store.has(r) && self.lazy_remote(r).is_some() {
1191 
            self.fetch_lazy_blob(r)?;
1192 
        }
98286406 Andy McCall ↶ 1193 
        let blob = Blob::decode(&self.store.get_typed(r, ObjectType::Blob)?)?;
1194 
        let mut out = Vec::with_capacity(blob.length as usize);
1195 
        for c in &blob.chunks {
1196 
            out.extend(self.store.get_typed(c, ObjectType::Chunk)?);
1197 
        }
1198 
        Ok(out)
1199 
    }
1200
1201 
    // ------------------------------------------------------------ working copy
1202
cdb5beba Andy McCall ↶ 1203 
    /// Attributes from the `.oxyattributes` files in the working directory.
1204 
    pub fn disk_attributes(&self) -> crate::attributes::Attributes {
f9466021 Andy McCall ↶ 1205 
        // Nested repositories and ignored paths are left out, as in a walk.
1206 
        let listing = walk::list(&self.root, &|p: &str| is_attributes(p)).unwrap_or_default();
1207 
        let files: Vec<(String, Vec<u8>)> = listing
1208 
            .files
1209 
            .into_iter()
1210 
            .filter_map(|(rel, path, _)| Some((rel, fs::read(path).ok()?)))
1211 
            .collect();
75167672 Andy McCall 1212 
        crate::attributes::Attributes::from_files(
1213 
            files.iter().map(|(p, c)| (p.as_str(), c.as_slice())),
1214 
        )
cdb5beba Andy McCall ↶ 1215 
    }
1216
d4dbab97 Andy McCall ↶ 1217 
    /// Folders holding a repository of their own that the last look at the
1218 
    /// working copy left out, not being subrepos (oxygen#43).
1219 
    pub fn untracked_nested(&self) -> Vec<String> {
1220 
        self.untracked_nested.borrow().clone()
1221 
    }
1222
cdb5beba Andy McCall ↶ 1223 
    /// Attributes from a materialized state's `.oxyattributes` files.
1224 
    pub fn state_attributes(snapshot: &Snapshot) -> crate::attributes::Attributes {
75167672 Andy McCall 1225 
        crate::attributes::Attributes::from_files(snapshot.files.iter().filter_map(|(p, f)| {
1226 
            match &f.content {
1227 
                FileContent::Text { bytes, .. }
1228 
                    if p == ".oxyattributes" || p.ends_with("/.oxyattributes") =>
1229 
                {
1230 
                    Some((p.as_str(), bytes.as_slice()))
1231 
                }
1232 
                _ => None,
1233 
            }
cdb5beba Andy McCall ↶ 1234 
        }))
1235 
    }
1236
1237 
    /// Store a blob, raw when the path is `nocompress`.
1238 
    pub fn store_blob_for(&self, content: &[u8], nocompress: bool) -> Result<ObjectRef> {
1239 
        if !nocompress {
1240 
            return self.store_blob(content);
1241 
        }
1242 
        for c in crate::chunk::chunks(content) {
1243 
            self.store.put_chunk_nocompress(c)?;
1244 
        }
75167672 Andy McCall 1245 
        Ok(self
1246 
            .store
1247 
            .put(ObjectType::Blob, &Self::blob_for(content).encode())?)
cdb5beba Andy McCall ↶ 1248 
    }
1249
f9575918 Andy McCall ↶ 1250 
    /// This workspace's state index (oxygen#41): its working copy's base,
1251 
    /// saved so a snapshot reads it rather than replaying history.
638fb214 Andy McCall ↶ 1252 
    /// The state index of the state with these heads: this workspace keeps
1253 
    /// the last few it used, named by their heads, so moving between two
1254 
    /// states finds both.
1255 
    fn state_index_path(&self, heads: &[ChangeHash]) -> PathBuf {
1256 
        let mut heads = heads.to_vec();
1257 
        heads.sort();
1258 
        let mut h = blake3::Hasher::new();
1259 
        for c in &heads {
1260 
            h.update(&c.0);
1261 
        }
1262 
        self.oxy.join("index").join(format!(
1263 
            "{}{}",
1264 
            self.state_index_prefix(),
1265 
            &h.finalize().to_hex()[..16]
1266 
        ))
f9575918 Andy McCall ↶ 1267 
    }
1268
638fb214 Andy McCall ↶ 1269 
    fn state_index_prefix(&self) -> String {
1270 
        format!("state-{}-", self.workspace.to_hex())
1271 
    }
1272
1273 
    /// This workspace's state indexes, newest first.
1274 
    fn state_indexes(&self) -> Vec<PathBuf> {
1275 
        let prefix = self.state_index_prefix();
1276 
        let mut found: Vec<(std::time::SystemTime, PathBuf)> = fs::read_dir(self.oxy.join("index"))
1277 
            .into_iter()
1278 
            .flatten()
1279 
            .flatten()
1280 
            .filter(|e| e.file_name().to_string_lossy().starts_with(&prefix))
1281 
            .filter_map(|e| Some((e.metadata().ok()?.modified().ok()?, e.path())))
1282 
            .collect();
1283 
        found.sort_by_key(|f| std::cmp::Reverse(f.0));
1284 
        found.into_iter().map(|(_, p)| p).collect()
1285 
    }
1286
f9575918 Andy McCall ↶ 1287 
    /// The history-only state of `deps` (as [`Repo::load_state_history`]),
1288 
    /// from this workspace's state index when it holds that history: every
1289 
    /// one of `deps` is in it and their heads are its heads. Otherwise it
1290 
    /// is loaded from history and indexed for next time.
1291 
    pub fn load_state_indexed(&self, deps: &[ChangeHash]) -> Result<State> {
638fb214 Andy McCall ↶ 1292 
        if let Some((st, heads)) = self.read_state_index(deps) {
f9466021 Andy McCall ↶ 1293 
            let mut have = st.maximal(deps);
1294 
            have.sort();
1295 
            if deps.iter().all(|d| st.contains(d)) && have == heads {
1296 
                #[cfg(test)]
1297 
                assert_eq!(
1298 
                    st.write_index(),
1299 
                    self.load_state_history(deps)?.write_index(),
1300 
                    "a state index holds the state history gives"
1301 
                );
1302 
                return Ok(st);
1303 
            }
1304 
            // An index a few changes behind (a commit, a pull since): add
1305 
            // what it lacks, as long as all it holds is history of `deps`.
1306 
            // Anything amiss (a change beyond a shallow boundary) takes the
1307 
            // long way instead.
1308 
            let (indexed, started) = (st.len(), std::time::Instant::now());
1309 
            if let Ok(st) = self.load_state_replayed(deps, st) {
1310 
                let mut all = deps.to_vec();
1311 
                all.extend(heads.iter().copied());
1312 
                let (mut within, mut want) = (st.maximal(&all), st.maximal(deps));
1313 
                within.sort();
1314 
                want.sort();
1315 
                if within == want {
1316 
                    #[cfg(test)]
1317 
                    self.assert_same_state(&st, &self.load_state_history(deps)?);
1318 
                    // Writing the index costs far more than replaying a
1319 
                    // few small changes: it is rewritten once it falls
1320 
                    // behind, or when replaying took long (large changes).
1321 
                    if st.len() - indexed > INDEX_REPLAY_LIMIT
1322 
                        || started.elapsed() > INDEX_REPLAY_TIME
1323 
                    {
1324 
                        self.write_state_index(deps, &st);
1325 
                    }
1326 
                    return Ok(st);
1327 
                }
1328 
            }
f9575918 Andy McCall ↶ 1329 
        }
1330 
        let st = self.load_state_history(deps)?;
1331 
        self.write_state_index(deps, &st);
1332 
        Ok(st)
f9466021 Andy McCall ↶ 1333 
    }
1334
1335 
    /// Two history-only states hold the same changes and render the same
1336 
    /// files. Their indexes may differ: one loaded from a checkpoint keeps
1337 
    /// the checkpoint's graphs as the bases of its files' histories.
1338 
    #[cfg(test)]
1339 
    fn assert_same_state(&self, a: &State, b: &State) {
1340 
        let ids = |s: &State| s.changes().map(|(h, _)| *h).collect::<BTreeSet<_>>();
1341 
        assert_eq!(ids(a), ids(b), "the same changes");
1342 
        let files = |s: &State| {
1343 
            let mut s = s.clone();
1344 
            self.load_all_graphs(&mut s).unwrap();
1345 
            s.materialize().files
1346 
        };
1347 
        assert_eq!(files(a), files(b), "the same files");
f9575918 Andy McCall ↶ 1348 
    }
1349
4cce912a Andy McCall ↶ 1350 
    /// The state index file: its heads, a hash of its changes block and one
1351 
    /// of the rest, then the body [`State::write_index`] gives, whose first
1352 
    /// block is the changes. Hashed in two parts so the log can read and
1353 
    /// check the changes alone.
638fb214 Andy McCall ↶ 1354 
    /// The index of `deps` if there is one, else the newest, which the
1355 
    /// caller may bring up to date.
1356 
    fn read_state_index(&self, deps: &[ChangeHash]) -> Option<(State, Vec<ChangeHash>)> {
f9575918 Andy McCall ↶ 1357 
        let _t = crate::timing::phase("load: state index");
638fb214 Andy McCall ↶ 1358 
        let exact = self.state_index_path(deps);
1359 
        let bytes = match fs::read(&exact) {
1360 
            Ok(b) => {
1361 
                // Used now: the newest, so the last to be dropped.
1362 
                let _ = fs::File::options()
1363 
                    .write(true)
1364 
                    .open(&exact)
1365 
                    .and_then(|f| f.set_modified(std::time::SystemTime::now()));
1366 
                b
1367 
            }
1368 
            Err(_) => fs::read(self.state_indexes().first()?).ok()?,
1369 
        };
f9575918 Andy McCall ↶ 1370 
        let mut r = crate::flat::Reader::new(&bytes);
1371 
        let mut heads = Vec::new();
1372 
        for _ in 0..r.count().ok()? {
1373 
            heads.push(r.object().ok()?);
1374 
        }
4cce912a Andy McCall ↶ 1375 
        let (changes_sum, rest_sum) = (r.object().ok()?, r.object().ok()?);
1376 
        let body = &bytes[4 + 32 * heads.len() + 64..];
1377 
        let split = 4 + r.count().ok()?;
1378 
        // Checked whole, so a part decoded later (the tree's maps, a
1379 
        // file's history) can trust its bytes.
1380 
        let (changes, rest) = (body.get(..split)?, body.get(split..)?);
05059d43 Andy McCall ↶ 1381 
        let mut h = blake3::Hasher::new();
4cce912a Andy McCall ↶ 1382 
        h.update_rayon(rest);
1383 
        if *blake3::hash(changes).as_bytes() != changes_sum.0
1384 
            || *h.finalize().as_bytes() != rest_sum.0
1385 
        {
f9575918 Andy McCall ↶ 1386 
            return None;
1387 
        }
f9466021 Andy McCall ↶ 1388 
        Some((State::read_index(body).ok()?, heads))
4cce912a Andy McCall ↶ 1389 
    }
1390
1391 
    /// The changes of this workspace's state index (the closure of its
1392 
    /// heads), read without the rest of the index.
1393 
    pub(crate) fn read_state_index_changes(
1394 
        &self,
1395 
    ) -> Option<std::collections::HashMap<ChangeHash, std::sync::Arc<crate::state::ChangeMeta>>>
1396 
    {
1397 
        use std::io::Read;
1398 
        let _t = crate::timing::phase("load: state index changes");
638fb214 Andy McCall ↶ 1399 
        let mut f = fs::File::open(self.state_indexes().first()?).ok()?;
4cce912a Andy McCall ↶ 1400 
        let mut word = [0u8; 4];
1401 
        f.read_exact(&mut word).ok()?;
1402 
        let n = u32::from_le_bytes(word) as usize;
1403 
        let mut head = vec![0u8; 32 * n + 64 + 4];
1404 
        f.read_exact(&mut head).ok()?;
1405 
        let sum = &head[32 * n..32 * n + 32];
1406 
        let len = u32::from_le_bytes(head[32 * n + 64..].try_into().unwrap()) as usize;
1407 
        let mut changes = vec![0u8; 4 + len];
1408 
        changes[..4].copy_from_slice(&head[32 * n + 64..]);
1409 
        f.read_exact(&mut changes[4..]).ok()?;
1410 
        if blake3::hash(&changes).as_bytes() != sum {
1411 
            return None;
1412 
        }
1413 
        State::read_index_changes(&changes[4..]).ok()
f9575918 Andy McCall ↶ 1414 
    }
1415
1416 
    /// Save `st`, the history-only state of `deps`, as this workspace's
1417 
    /// state index; quietly nothing when it cannot be (it is only a cache).
1418 
    pub(crate) fn write_state_index(&self, deps: &[ChangeHash], st: &State) {
1419 
        let _t = crate::timing::phase("write: state index");
f9466021 Andy McCall ↶ 1420 
        let encoding = crate::timing::phase("write:   of which encoding");
f9575918 Andy McCall ↶ 1421 
        let Some(body) = st.write_index() else {
1422 
            return;
1423 
        };
f9466021 Andy McCall ↶ 1424 
        drop(encoding);
3f1b8fe2 Andy McCall ↶ 1425 
        #[cfg(test)]
1426 
        assert_eq!(
1427 
            State::read_index(&body).ok().and_then(|s| s.write_index()),
1428 
            Some(body.clone()),
1429 
            "a state index reads back as written"
1430 
        );
f9575918 Andy McCall ↶ 1431 
        let mut heads = st.maximal(deps);
1432 
        heads.sort();
1433 
        let mut w = crate::flat::Writer::default();
1434 
        w.count(heads.len());
1435 
        for h in &heads {
1436 
            w.object(h);
1437 
        }
4cce912a Andy McCall ↶ 1438 
        let split = 4 + u32::from_le_bytes(body[..4].try_into().unwrap()) as usize;
1439 
        w.fixed(blake3::hash(&body[..split]).as_bytes());
05059d43 Andy McCall ↶ 1440 
        let mut sum = blake3::Hasher::new();
4cce912a Andy McCall ↶ 1441 
        sum.update_rayon(&body[split..]);
05059d43 Andy McCall ↶ 1442 
        w.fixed(sum.finalize().as_bytes());
f9575918 Andy McCall ↶ 1443 
        w.fixed(&body);
638fb214 Andy McCall ↶ 1444 
        let path = self.state_index_path(&heads);
f9466021 Andy McCall ↶ 1445 
        let _ = fs::create_dir_all(self.oxy.join("index"));
1446 
        let _ = write_cache(&path, &w.0);
638fb214 Andy McCall ↶ 1447 
        // The last two used: the index of a state moved away from stays for
1448 
        // a move back. Older ones (and the unnamed one of before) go.
1449 
        for old in self.state_indexes().iter().skip(STATE_INDEXES_KEPT) {
1450 
            let _ = fs::remove_file(old);
1451 
        }
1452 
        let _ = fs::remove_file(
1453 
            self.oxy
1454 
                .join("index")
1455 
                .join(format!("state-{}", self.workspace.to_hex())),
1456 
        );
f9575918 Andy McCall ↶ 1457 
    }
1458
cdb5beba Andy McCall ↶ 1459 
    fn locks_dir(&self) -> PathBuf {
1460 
        self.oxy.join("locks")
1461 
    }
1462
1463 
    /// Whether `path` is locked locally for editing (spec §18, advisory).
1464 
    pub fn is_locked(&self, path: &str) -> bool {
1465 
        self.locks_dir().join(path.replace('/', "%2F")).exists()
1466 
    }
1467
1468 
    /// Take the advisory local lock on a `lockable` file and make it writable.
1469 
    pub fn lock_path(&self, path: &str) -> Result<()> {
1470 
        let attrs = self.disk_attributes();
1471 
        if !attrs.lookup(path).lockable {
1472 
            return fail(format!("{path} is not marked lockable in .oxyattributes"));
1473 
        }
1474 
        fs::create_dir_all(self.locks_dir())?;
75167672 Andy McCall 1475 
        write_atomic(
1476 
            &self.locks_dir().join(path.replace('/', "%2F")),
1477 
            std::process::id().to_string().as_bytes(),
1478 
        )?;
cdb5beba Andy McCall ↶ 1479 
        set_readonly(&self.root.join(path), false)?;
1480 
        Ok(())
1481 
    }
1482
1483 
    /// Release the local lock and make the file read-only again.
1484 
    pub fn unlock_path(&self, path: &str) -> Result<()> {
1485 
        let _ = fs::remove_file(self.locks_dir().join(path.replace('/', "%2F")));
1486 
        if self.root.join(path).exists() {
1487 
            set_readonly(&self.root.join(path), true)?;
1488 
        }
1489 
        Ok(())
1490 
    }
1491
7421309f Andy McCall ↶ 1492 
    /// Whether a repository path is inside the sparse filter (spec §17).
1493 
    pub fn in_scope(&self, path: &str) -> bool {
75167672 Andy McCall 1494 
        self.config.sparse_paths.is_empty()
1495 
            || self
1496 
                .config
1497 
                .sparse_paths
1498 
                .iter()
1499 
                .any(|p| path == p || path.starts_with(&format!("{p}/")))
7421309f Andy McCall ↶ 1500 
    }
1501
98286406 Andy McCall ↶ 1502 
    fn walk_working_copy(&self) -> Result<BTreeMap<String, FsEntry>> {
696bbf29 Andy McCall ↶ 1503 
        self.walk_working_copy_with(None, &BTreeMap::new(), None)
4dee277c Andy McCall ↶ 1504 
    }
1505
b7f102fc Andy McCall ↶ 1506 
    /// Walk the working copy; with a manifest, a file whose size and mtime
cc7a0056 Andy McCall ↶ 1507 
    /// match it is not read: an opaque file yields its known blob, and a
1508 
    /// text file whose recorded graph key equals its base graph's key in
1509 
    /// `keys` (path → key) is marked unchanged; other text files are read
1510 
    /// but keep their known hash. Files modified within two seconds of the
1511 
    /// manifest are never trusted (a racy stat).
1512 
    ///
1513 
    /// `.oxyattributes` files are always read, since their content is
1514 
    /// needed; and when any of them is not known unchanged (added, removed,
1515 
    /// edited, or changed in the base), no text file is taken as unchanged,
1516 
    /// because attributes decide how a file compares with the base.
9ac1fbe2 Andy McCall ↶ 1517 
    ///
1518 
    /// `.oxyignore` applies to untracked paths only: every path in `tracked`
1519 
    /// (the base state's files) that exists on disk is included even when
1520 
    /// an ignore rule matches it, as in Git.
75167672 Andy McCall 1521 
    fn walk_working_copy_with(
1522 
        &self,
1523 
        cache: Option<&prompt::Manifest>,
1524 
        tracked: &BTreeMap<String, (NodeKind, Option<ObjectRef>)>,
992467d3 Andy McCall ↶ 1525 
        keys: Option<&KeyOf>,
75167672 Andy McCall 1526 
    ) -> Result<BTreeMap<String, FsEntry>> {
36e51aa8 Andy McCall ↶ 1527 
        let mut out: BTreeMap<String, FsEntry>;
76740263 Andy McCall ↶ 1528 
        let sparse = &self.config.sparse_paths;
8b276e01 Andy McCall ↶ 1529 
        let in_scope = |p: &str| {
1530 
            sparse.is_empty()
1531 
                || sparse
1532 
                    .iter()
1533 
                    .any(|s| p == s || p.starts_with(&format!("{s}/")))
1534 
        };
76740263 Andy McCall ↶ 1535 
        let walk_phase = crate::timing::phase("walk:   of which listing");
1536 
        let walk::Listing {
1537 
            files,
1538 
            symlinks,
1539 
            nested,
1540 
        } = match self.listing_cache.take() {
1541 
            Some(l) => l,
d4dbab97 Andy McCall ↶ 1542 
            // Ignore rules apply to untracked paths only, so the base's
1543 
            // files are not matched against them (an added file is: a rule
1544 
            // written after it was snapshotted leaves it out again).
1545 
            None => walk::list_knowing(&self.root, &in_scope, &|p: &str| tracked.contains_key(p))?,
76740263 Andy McCall ↶ 1546 
        };
cc7a0056 Andy McCall ↶ 1547 
        let keys = keys.filter(|k| {
1548 
            let on_disk: HashSet<&str> = files.iter().map(|(r, _, _)| r.as_str()).collect();
1549 
            let attrs_unchanged =
1550 
                files
1551 
                    .iter()
1552 
                    .filter(|(r, _, _)| is_attributes(r))
1553 
                    .all(|(rel, _, meta)| {
1554 
                        stat_cached(rel, meta, cache)
992467d3 Andy McCall ↶ 1555 
                            .is_some_and(|e| e.graph.is_some() && e.graph == k(rel))
cc7a0056 Andy McCall ↶ 1556 
                    });
1557 
            let none_removed = tracked
1558 
                .keys()
1559 
                .filter(|r| is_attributes(r))
1560 
                .all(|r| on_disk.contains(r.as_str()));
1561 
            attrs_unchanged && none_removed
1562 
        });
76740263 Andy McCall ↶ 1563 
        drop(walk_phase);
1564 
        let _read_phase = crate::timing::phase("walk:   of which stat and compare");
e7ddd552 Andy McCall ↶ 1565 
        // Reading files is most of a walk's cost; do it in parallel.
1566 
        {
1567 
            use rayon::prelude::*;
36e51aa8 Andy McCall ↶ 1568 
            let mut read: Vec<(String, FsEntry)> = files
e7ddd552 Andy McCall ↶ 1569 
                .par_iter()
1570 
                .map(|(rel, path, meta)| {
992467d3 Andy McCall ↶ 1571 
                    // A key is worked out only for a file the manifest
1572 
                    // knows with the same stat and a key of its own.
cc7a0056 Andy McCall ↶ 1573 
                    let key = keys
1574 
                        .filter(|_| !is_attributes(rel))
992467d3 Andy McCall ↶ 1575 
                        .filter(|_| {
1576 
                            stat_cached(rel, meta, cache).is_some_and(|e| e.graph.is_some())
1577 
                        })
1578 
                        .and_then(|k| k(rel));
1966f5db Andy McCall ↶ 1579 
                    Ok((rel.clone(), read_file_entry(rel, path, meta, cache, key)?))
e7ddd552 Andy McCall ↶ 1580 
                })
1581 
                .collect::<Result<Vec<_>>>()?;
36e51aa8 Andy McCall ↶ 1582 
            for (rel, e) in read.iter_mut() {
e7ddd552 Andy McCall ↶ 1583 
                // A cached blob the store lost (gc, a partial clone): read the file after all.
1584 
                if e.content.is_empty() && e.blob.is_some_and(|b| !self.store.has(&b)) {
36e51aa8 Andy McCall ↶ 1585 
                    e.content = std::sync::Arc::new(fs::read(self.root.join(rel.as_str()))?);
e7ddd552 Andy McCall ↶ 1586 
                    e.blob = None;
1587 
                }
36e51aa8 Andy McCall ↶ 1588 
            }
1589 
            // The listing is in path order, so the map is built without
1590 
            // searching.
1591 
            out = read.into_iter().collect();
1592 
            for (rel, target) in symlinks {
1593 
                out.insert(rel, FsEntry::new(NodeKind::Symlink, false, target));
98286406 Andy McCall ↶ 1594 
            }
1595 
        }
76740263 Andy McCall ↶ 1596 
        drop(_read_phase);
1597 
        let _rest = crate::timing::phase("walk:   of which subrepos and hidden");
4dee277c Andy McCall ↶ 1598 
        // Nested repositories (spec §7.8): registered in `.oxymodules` or
1599 
        // already tracked as subrepo nodes, they contribute their pin;
1600 
        // unregistered ones are left alone.
1601 
        let modules = self.modules_on_disk();
1602 
        let removed = self.removed_subrepos();
1603 
        for rel in &removed {
1604 
            if tracked.get(rel).map(|(k, _)| *k) != Some(NodeKind::Subrepo) {
1605 
                self.clear_removed_subrepo(rel);
1606 
            }
1607 
        }
d4dbab97 Andy McCall ↶ 1608 
        let mut untracked_nested = Vec::new();
76740263 Andy McCall ↶ 1609 
        for dir in nested {
4dee277c Andy McCall ↶ 1610 
            let rel = self.rel_path(&dir);
1611 
            if !self.in_scope(&rel) || removed.contains(&rel) {
1612 
                continue;
1613 
            }
1614 
            let registered = modules.entries.get(&rel);
75167672 Andy McCall 1615 
            if registered.is_none() && tracked.get(&rel).map(|(k, _)| *k) != Some(NodeKind::Subrepo)
1616 
            {
d4dbab97 Andy McCall ↶ 1617 
                untracked_nested.push(rel);
4dee277c Andy McCall ↶ 1618 
                continue;
1619 
            }
1620 
            let pin = subrepos::read_pin(&dir, registered.and_then(|m| m.bookmark.as_deref()))?;
1621 
            out.insert(rel, FsEntry::new(NodeKind::Subrepo, false, pin.encode()));
1622 
        }
d4dbab97 Andy McCall ↶ 1623 
        untracked_nested.sort();
1624 
        *self.untracked_nested.borrow_mut() = untracked_nested;
9ac1fbe2 Andy McCall ↶ 1625 
        // Tracked paths the ignore rules hid.
f57bf670 Andy McCall ↶ 1626 
        for (rel, (kind, blob)) in missing_from(tracked, &out) {
1627 
            if !self.in_scope(rel) {
9ac1fbe2 Andy McCall ↶ 1628 
                continue;
1629 
            }
1630 
            let path = self.root.join(rel);
4dee277c Andy McCall ↶ 1631 
            if *kind == NodeKind::Subrepo {
1632 
                if removed.contains(rel) {
1633 
                    continue;
1634 
                }
75167672 Andy McCall 1635 
                let present =
1636 
                    path.is_dir() && (path.join(OXY_DIR).exists() || path.join(".git").exists());
4dee277c Andy McCall ↶ 1637 
                if present {
75167672 Andy McCall 1638 
                    let pin = subrepos::read_pin(
1639 
                        &path,
1640 
                        modules.entries.get(rel).and_then(|m| m.bookmark.as_deref()),
1641 
                    )?;
1642 
                    out.insert(
1643 
                        rel.clone(),
1644 
                        FsEntry::new(NodeKind::Subrepo, false, pin.encode()),
1645 
                    );
4dee277c Andy McCall ↶ 1646 
                } else if let Some(b) = blob {
1647 
                    // Not cloned (or emptied): the pin stays as recorded, as a
1648 
                    // Git gitlink does when its directory is absent.
75167672 Andy McCall 1649 
                    out.insert(
1650 
                        rel.clone(),
1651 
                        FsEntry {
1652 
                            blob: Some(*b),
cc7a0056 Andy McCall ↶ 1653 
                            ..FsEntry::new(NodeKind::Subrepo, false, vec![])
75167672 Andy McCall 1654 
                        },
1655 
                    );
4dee277c Andy McCall ↶ 1656 
                }
1657 
                continue;
1658 
            }
75167672 Andy McCall 1659 
            let Ok(meta) = fs::symlink_metadata(&path) else {
1660 
                continue;
1661 
            };
9ac1fbe2 Andy McCall ↶ 1662 
            let ft = meta.file_type();
1663 
            if ft.is_symlink() {
1664 
                let target = fs::read_link(&path)?;
75167672 Andy McCall 1665 
                out.insert(
1666 
                    rel.clone(),
1667 
                    FsEntry::new(
1668 
                        NodeKind::Symlink,
1669 
                        false,
1670 
                        target.to_string_lossy().as_bytes().to_vec(),
1671 
                    ),
1672 
                );
9ac1fbe2 Andy McCall ↶ 1673 
            } else if ft.is_file() {
1674 
                let e = self.file_entry(rel, &path, &meta, cache)?;
1675 
                out.insert(rel.clone(), e);
1676 
            }
1677 
        }
98286406 Andy McCall ↶ 1678 
        Ok(out)
1679 
    }
9ac1fbe2 Andy McCall ↶ 1680
1681 
    /// The entry for one regular file, read or served from the stat cache.
75167672 Andy McCall 1682 
    fn file_entry(
1683 
        &self,
1684 
        rel: &str,
1685 
        path: &Path,
1686 
        meta: &fs::Metadata,
1687 
        cache: Option<&prompt::Manifest>,
1688 
    ) -> Result<FsEntry> {
696bbf29 Andy McCall ↶ 1689 
        let mut e = read_file_entry(rel, path, meta, cache, None)?;
e7ddd552 Andy McCall ↶ 1690 
        if e.content.is_empty() && e.blob.is_some_and(|b| !self.store.has(&b)) {
40a40bb7 Andy McCall ↶ 1691 
            e.content = std::sync::Arc::new(fs::read(path)?);
e7ddd552 Andy McCall ↶ 1692 
            e.blob = None;
1693 
        }
1694 
        Ok(e)
9ac1fbe2 Andy McCall ↶ 1695 
    }
1696
4dee277c Andy McCall ↶ 1697 
    /// The non-directory paths of a snapshot with their kinds, for the
1698 
    /// walker's `tracked` set.
75167672 Andy McCall 1699 
    pub(crate) fn tracked_kinds(
1700 
        snapshot: &Snapshot,
1701 
    ) -> BTreeMap<String, (NodeKind, Option<ObjectRef>)> {
4dee277c Andy McCall ↶ 1702 
        snapshot
1703 
            .files
1704 
            .iter()
1705 
            .filter(|(_, f)| f.kind != NodeKind::Dir)
1706 
            .map(|(p, f)| {
1707 
                let blob = match &f.content {
1708 
                    FileContent::Opaque { blobs } => blobs.first().copied(),
1709 
                    _ => None,
1710 
                };
1711 
                (p.clone(), (f.kind, blob))
1712 
            })
1713 
            .collect()
1714 
    }
1715
1716 
    /// A path under the root as a `/`-separated relative string.
1717 
    pub(crate) fn rel_path(&self, path: &Path) -> String {
75167672 Andy McCall 1718 
        path.strip_prefix(&self.root)
1719 
            .unwrap_or(path)
1720 
            .components()
1721 
            .map(|c| c.as_os_str().to_string_lossy().to_string())
1722 
            .collect::<Vec<_>>()
1723 
            .join("/")
9ac1fbe2 Andy McCall ↶ 1724 
    }
98286406 Andy McCall ↶ 1725 
}
1726
1727 
impl Repo {
1728 
    /// Changes reachable from the bookmark and the working copy, newest first.
1729 
    pub fn log(&self) -> Result<Vec<LogEntry>> {
e02bf0cd Andy McCall ↶ 1730 
        let heads = self.bookmark_heads()?;
1731 
        if self.bare {
1732 
            return self.log_state(&heads);
1733 
        }
98286406 Andy McCall ↶ 1734 
        let (wc_hash, _) = self.working_copy()?;
e02bf0cd Andy McCall ↶ 1735 
        let mut all = heads.clone();
1736 
        all.push(wc_hash);
1737 
        let head_set: BTreeSet<ChangeHash> = heads.into_iter().collect();
252e8cb2 Andy McCall ↶ 1738 
        let mut entries: Vec<LogEntry> = Vec::new();
4d6c9c1b Andy McCall ↶ 1739 
        // A shallow clone knows changes beyond its boundary from a
1740 
        // checkpoint's metadata only: its log comes from the state.
1741 
        let metas = if self.is_shallow() {
1742 
            self.load_state_history(&all)?
1743 
                .changes()
1744 
                .map(|(h, m)| (*h, m.clone()))
1745 
                .collect()
1746 
        } else {
1747 
            self.metas_of(&all)?
1748 
        };
1749 
        for (h, meta) in metas {
75167672 Andy McCall 1750 
            entries.push(LogEntry {
4d6c9c1b Andy McCall ↶ 1751 
                hash: h,
1752 
                change: meta,
1753 
                is_working_copy: h == wc_hash,
1754 
                is_head: head_set.contains(&h),
75167672 Andy McCall 1755 
            });
252e8cb2 Andy McCall ↶ 1756 
        }
75167672 Andy McCall 1757 
        entries.sort_by(|a, b| {
1758 
            b.is_working_copy
1759 
                .cmp(&a.is_working_copy)
1760 
                .then(b.change.hlc.cmp(&a.change.hlc))
1761 
                .then(b.hash.cmp(&a.hash))
1762 
        });
98286406 Andy McCall ↶ 1763 
        Ok(entries)
1764 
    }
1765
119bbf50 Andy McCall ↶ 1766 
    /// A window of `log_state`: entries `offset..offset+limit` and the total
1767 
    /// count, for paginated views.
9d333fc9 Andy McCall ↶ 1768 
    pub fn log_window(
1769 
        &self,
1770 
        heads: &[ChangeHash],
1771 
        offset: usize,
1772 
        limit: usize,
1773 
    ) -> Result<(Vec<LogEntry>, usize)> {
119bbf50 Andy McCall ↶ 1774 
        let all = self.log_state(heads)?;
1775 
        let total = all.len();
1776 
        Ok((all.into_iter().skip(offset).take(limit).collect(), total))
1777 
    }
1778
e02bf0cd Andy McCall ↶ 1779 
    /// The log of the state with these heads, newest first, with no working
1780 
    /// copy involved (for hosted repositories and any explicit state).
1781 
    pub fn log_state(&self, heads: &[ChangeHash]) -> Result<Vec<LogEntry>> {
4d6c9c1b Andy McCall ↶ 1782 
        // The log needs change metadata only: neither graphs nor the tree.
1783 
        if self.is_shallow() {
1784 
            return Ok(self.log_of(&self.load_state_history(heads)?));
1785 
        }
1786 
        let metas = self.metas_of(heads)?;
1787 
        let depended: BTreeSet<ChangeHash> = metas
1788 
            .iter()
1789 
            .flat_map(|(_, m)| m.deps.iter().copied())
1790 
            .collect();
1791 
        let mut entries: Vec<LogEntry> = metas
1792 
            .into_iter()
1793 
            .map(|(h, meta)| LogEntry {
1794 
                hash: h,
1795 
                is_head: !depended.contains(&h),
1796 
                change: meta,
1797 
                is_working_copy: false,
1798 
            })
1799 
            .collect();
1800 
        entries.sort_by(|a, b| b.change.hlc.cmp(&a.change.hlc).then(b.hash.cmp(&a.hash)));
1801 
        Ok(entries)
1802 
    }
1803
1804 
    /// Every change of the state with these heads and its metadata, read
1805 
    /// without its operations ([`Store::get_change_meta`]). A change beyond
1806 
    /// a shallow clone's boundary is left out.
1807 
    pub fn metas_of(
1808 
        &self,
1809 
        heads: &[ChangeHash],
1810 
    ) -> Result<Vec<(ChangeHash, crate::state::ChangeMeta)>> {
1811 
        let boundary = self.boundary();
4cce912a Andy McCall ↶ 1812 
        // The state index holds the metadata of its heads' closure: a
1813 
        // change found there is not read from the store (a change object
1814 
        // can be as large as the tree it adds).
1815 
        let indexed = self.read_state_index_changes();
1816 
        let (mut stored, mut from_store) = (0usize, std::time::Duration::ZERO);
4d6c9c1b Andy McCall ↶ 1817 
        let mut seen: HashSet<ChangeHash> = HashSet::new();
1818 
        let mut stack: Vec<ChangeHash> = heads.to_vec();
1819 
        let mut out = Vec::new();
1820 
        while let Some(h) = stack.pop() {
1821 
            if !seen.insert(h) {
1822 
                continue;
1823 
            }
4cce912a Andy McCall ↶ 1824 
            if let Some(meta) = indexed.as_ref().and_then(|m| m.get(&h)) {
1825 
                #[cfg(test)]
1826 
                assert_eq!(
1827 
                    **meta,
1828 
                    self.store.get_change_meta(&h)?,
1829 
                    "the state index holds a change's metadata"
1830 
                );
1831 
                stack.extend(meta.deps.iter().copied());
1832 
                out.push((h, (**meta).clone()));
1833 
                continue;
1834 
            }
1835 
            let started = std::time::Instant::now();
4d6c9c1b Andy McCall ↶ 1836 
            let meta = match self.store.get_change_meta(&h) {
1837 
                Ok(m) => m,
1838 
                Err(crate::store::StoreError::NotFound(_)) if boundary.contains(&h) => continue,
1839 
                Err(e) => return Err(e.into()),
1840 
            };
4cce912a Andy McCall ↶ 1841 
            stored += 1;
1842 
            from_store += started.elapsed();
4d6c9c1b Andy McCall ↶ 1843 
            stack.extend(meta.deps.iter().copied());
1844 
            out.push((h, meta));
4cce912a Andy McCall ↶ 1845 
        }
1846 
        if stored > 0 && crate::timing::enabled() {
1847 
            eprintln!("timing metadata: {stored} changes read whole, {from_store:.2?}");
4d6c9c1b Andy McCall ↶ 1848 
        }
1849 
        Ok(out)
bc489b6c Andy McCall ↶ 1850 
    }
1851
1852 
    /// The log of a state already loaded, newest first.
83d61e80 Andy McCall ↶ 1853 
    /// The history of lines `first..=last` (1-based) of `path` in the
1854 
    /// state `heads` make (spec §27): every change that inserted or
1855 
    /// deleted one of their atoms, or an atom deleted from between them,
1856 
    /// newest first. Exact, as atoms keep their identity across edits.
1857 
    pub fn line_history(
1858 
        &self,
1859 
        heads: &[ChangeHash],
1860 
        path: &str,
1861 
        first: usize,
1862 
        last: usize,
1863 
    ) -> Result<Vec<LogEntry>> {
1864 
        if first == 0 || last < first {
1865 
            return fail(format!(
1866 
                "lines {first},{last}: expected FIRST,LAST from 1 with FIRST ≤ LAST"
1867 
            ));
1868 
        }
1869 
        let mut state = self.load_state_history(heads)?;
1870 
        let Some(node) = state.tree().view().entries.get(path).map(|e| e.node) else {
1871 
            return fail(format!("{path} is not in that state"));
1872 
        };
1873 
        self.load_graphs_of(&mut state, &[node])?;
1874 
        let live = state.live_lines(&node);
1875 
        if last > live.len() {
1876 
            return fail(format!(
1877 
                "{path} has {} lines; asked for {first},{last}",
1878 
                live.len()
1879 
            ));
1880 
        }
1881 
        let Some(g) = state.file(&node) else {
1882 
            return fail(format!("{path} is not a text file"));
1883 
        };
1884 
        let atoms = g.between(&live[first - 1].0, &live[last - 1].0);
1885 
        let touched = g.touching(&atoms);
1886 
        Ok(self
1887 
            .log_of(&state)
1888 
            .into_iter()
1889 
            .filter(|e| touched.contains(&e.hash))
1890 
            .collect())
1891 
    }
1892
bc489b6c Andy McCall ↶ 1893 
    pub fn log_of(&self, state: &crate::state::State) -> Vec<LogEntry> {
e02bf0cd Andy McCall ↶ 1894 
        let head_set: BTreeSet<ChangeHash> = state.heads().into_iter().collect();
1895 
        let mut entries: Vec<LogEntry> = state
1896 
            .changes()
75167672 Andy McCall 1897 
            .map(|(h, meta)| LogEntry {
1898 
                hash: *h,
1899 
                change: meta.clone(),
1900 
                is_working_copy: false,
1901 
                is_head: head_set.contains(h),
1902 
            })
e02bf0cd Andy McCall ↶ 1903 
            .collect();
1904 
        entries.sort_by(|a, b| b.change.hlc.cmp(&a.change.hlc).then(b.hash.cmp(&a.hash)));
bc489b6c Andy McCall ↶ 1905 
        entries
e02bf0cd Andy McCall ↶ 1906 
    }
1907
14edbaaf Andy McCall ↶ 1908 
    /// Resolve a spec to a set of heads: a bookmark's name, a remote's
1909 
    /// bookmark as `REMOTE/NAME`, a tag name, or a single change
1910 
    /// (`resolve_change`).
132b884b Andy McCall ↶ 1911 
    pub fn resolve_heads(&self, spec: &str) -> Result<Vec<ChangeHash>> {
7b9809e6 Andy McCall ↶ 1912 
        let view = self.view()?;
1913 
        if let Some(st) = view.bookmarks.get(spec) {
1914 
            return Ok(self.store.get_state(st)?.heads);
132b884b Andy McCall ↶ 1915 
        }
14edbaaf Andy McCall ↶ 1916 
        if let Some((_, _, st)) = remote_bookmark(&view, spec) {
1917 
            return Ok(self.store.get_state(&st)?.heads);
1918 
        }
132b884b Andy McCall ↶ 1919 
        if let Some(heads) = self.tag_heads(spec)? {
1920 
            return Ok(heads);
1921 
        }
1922 
        Ok(vec![self.resolve_change(spec)?])
1923 
    }
1924
6a81dbab Andy McCall ↶ 1925 
    /// Resolve a change by ChangeId prefix, `#hash` prefix, `@` (working
14edbaaf Andy McCall ↶ 1926 
    /// copy), bookmark, `REMOTE/NAME` or tag (the one head of its state).
98286406 Andy McCall ↶ 1927 
    pub fn resolve_change(&self, spec: &str) -> Result<ChangeHash> {
1928 
        if spec == "@" {
1929 
            return Ok(self.working_copy()?.0);
1930 
        }
14edbaaf Andy McCall ↶ 1931 
        let view = self.view()?;
1932 
        let named = match view.bookmarks.get(spec) {
6a81dbab Andy McCall ↶ 1933 
            Some(st) => Some(("bookmark", self.store.get_state(st)?.heads)),
14edbaaf Andy McCall ↶ 1934 
            None => match remote_bookmark(&view, spec) {
1935 
                Some((_, _, st)) => Some(("bookmark", self.store.get_state(&st)?.heads)),
1936 
                None => self.tag_heads(spec)?.map(|h| ("tag", h)),
1937 
            },
6a81dbab Andy McCall ↶ 1938 
        };
1939 
        if let Some((kind, heads)) = named {
7b9809e6 Andy McCall ↶ 1940 
            return match heads.len() {
1941 
                1 => Ok(heads[0]),
6a81dbab Andy McCall ↶ 1942 
                n => fail(format!("{kind} {spec} has {n} heads; name a change, or use it where a state is expected")),
7b9809e6 Andy McCall ↶ 1943 
            };
1944 
        }
98286406 Andy McCall ↶ 1945 
        if spec.is_empty() || spec == "#" {
1946 
            return fail("empty change specifier");
1947 
        }
1948 
        let entries = self.log()?;
1949 
        let matches: Vec<&LogEntry> = if let Some(hp) = spec.strip_prefix('#') {
75167672 Andy McCall 1950 
            entries
1951 
                .iter()
1952 
                .filter(|e| e.hash.starts_with_hex(hp))
1953 
                .collect()
98286406 Andy McCall ↶ 1954 
        } else {
75167672 Andy McCall 1955 
            entries
1956 
                .iter()
1957 
                .filter(|e| e.change.change_id.starts_with_hex(spec))
1958 
                .collect()
98286406 Andy McCall ↶ 1959 
        };
1960 
        match matches.len() {
1961 
            1 => Ok(matches[0].hash),
1962 
            0 => fail(format!("no change matches {spec:?}")),
1963 
            _ => {
1964 
                let ids: BTreeSet<ChangeId> = matches.iter().map(|e| e.change.change_id).collect();
1965 
                if ids.len() == 1 {
75167672 Andy McCall 1966 
                    fail(format!(
1967 
                        "change {spec} is divergent: {} variants",
1968 
                        matches.len()
1969 
                    ))
98286406 Andy McCall ↶ 1970 
                } else {
1971 
                    fail(format!("{spec:?} is ambiguous"))
1972 
                }
1973 
            }
1974 
        }
1975 
    }
1976
1977 
    /// Human-readable description of what a change does, with line content.
1978 
    pub fn describe_change(&self, hash: &ChangeHash) -> Result<String> {
1979 
        let change = self.store.get_change(hash)?;
8ab265dc Andy McCall ↶ 1980 
        let (base, base_snapshot) = self.change_base(&change)?;
98286406 Andy McCall ↶ 1981 
        Ok(render_change(&change, &base, &base_snapshot))
8ab265dc Andy McCall ↶ 1982 
    }
1983
1984 
    /// The base state of `change` (its dependencies) and its rendering, as
1985 
    /// much as showing the change needs: the whole tree, and the graphs and
1986 
    /// contents of the files the change edits. Other text files are left
1987 
    /// unrendered ([`Snapshot::unrendered`]).
1988 
    pub fn change_base(&self, change: &Change) -> Result<(State, Snapshot)> {
1989 
        let mut base = self.load_state_history(&change.deps)?;
1990 
        let edited: std::collections::HashSet<NodeId> =
1991 
            change.edits.iter().map(|e| e.node()).collect();
1992 
        let nodes: Vec<NodeId> = edited.iter().copied().collect();
1993 
        self.load_graphs_of(&mut base, &nodes)?;
1994 
        let skip: std::collections::HashSet<NodeId> = base
1995 
            .tree()
1996 
            .view()
1997 
            .entries
1998 
            .values()
1999 
            .filter(|e| e.kind == crate::objects::NodeKind::File && !edited.contains(&e.node))
2000 
            .map(|e| e.node)
2001 
            .collect();
2002 
        let snapshot = base.materialize_except(&skip);
2003 
        Ok((base, snapshot))
98286406 Andy McCall ↶ 2004 
    }
2005 
}
2006
2007 
fn remove_any(path: &Path) -> std::io::Result<()> {
2008 
    let m = fs::symlink_metadata(path)?;
75167672 Andy McCall 2009 
    if m.is_dir() {
2010 
        fs::remove_dir_all(path)
2011 
    } else {
2012 
        fs::remove_file(path)
2013 
    }
98286406 Andy McCall ↶ 2014 
}
2015
cdb5beba Andy McCall ↶ 2016 
fn set_readonly(path: &Path, readonly: bool) -> std::io::Result<()> {
2017 
    let mut perms = fs::metadata(path)?.permissions();
2018 
    perms.set_readonly(readonly);
2019 
    fs::set_permissions(path, perms)
2020 
}
2021
98286406 Andy McCall ↶ 2022 
#[cfg(unix)]
2023 
fn set_executable(path: &Path, exec: bool) -> std::io::Result<()> {
2024 
    use std::os::unix::fs::PermissionsExt;
2025 
    let mut perms = fs::metadata(path)?.permissions();
2026 
    let mode = perms.mode();
2027 
    let want = if exec { mode | 0o111 } else { mode & !0o111 };
2028 
    if want != mode {
2029 
        perms.set_mode(want);
2030 
        fs::set_permissions(path, perms)?;
2031 
    }
2032 
    Ok(())
2033 
}
2034 
#[cfg(not(unix))]
2035 
fn set_executable(_path: &Path, _exec: bool) -> std::io::Result<()> {
2036 
    Ok(())
2037 
}
2038
2039 
#[cfg(unix)]
2040 
fn is_executable(m: &fs::Metadata) -> bool {
2041 
    use std::os::unix::fs::PermissionsExt;
2042 
    m.permissions().mode() & 0o111 != 0
2043 
}
2044 
#[cfg(not(unix))]
2045 
fn is_executable(_m: &fs::Metadata) -> bool {
2046 
    false
2047 
}
2048
2049 
fn op_ref(k: OpKey) -> OpRef {
75167672 Andy McCall 2050 
    OpRef {
2051 
        change: k.0,
2052 
        index: k.1,
2053 
    }
98286406 Andy McCall ↶ 2054 
}
2055
2056 
fn split_path(path: &str) -> (&str, &str) {
2057 
    match path.rfind('/') {
2058 
        Some(i) => (&path[..i], &path[i + 1..]),
2059 
        None => ("", path),
2060 
    }
cc7a0056 Andy McCall ↶ 2061 
}
2062
2063 
/// Whether `rel` is an attributes file (spec §7.6).
2064 
fn is_attributes(rel: &str) -> bool {
2065 
    rel == ".oxyattributes" || rel.ends_with("/.oxyattributes")
98286406 Andy McCall ↶ 2066 
}
e7ddd552 Andy McCall ↶ 2067
cc7a0056 Andy McCall ↶ 2068 
/// The manifest entry for `rel` when its size and mtime match it outside
2069 
/// the racy window.
2070 
fn stat_cached<'m>(
2071 
    rel: &str,
2072 
    meta: &fs::Metadata,
2073 
    cache: Option<&'m prompt::Manifest>,
2074 
) -> Option<&'m prompt::ManifestEntry> {
2075 
    let m = cache?;
2076 
    let e = m.entries.get(rel)?;
2077 
    let mtime_ns = prompt::mtime_ns(meta);
2078 
    let racy = mtime_ns + 2_000_000_000 >= m.written_ns;
2079 
    (e.size == meta.len() && e.mtime_ns == mtime_ns && !racy).then_some(e)
2080 
}
2081
2082 
/// Read one working-copy file, or serve it from the stat cache (spec
2083 
/// §12.3). With a manifest whose stat for it is unchanged (and not racy),
2084 
/// an opaque file is not read at all (its stored blob stands in), and a
2085 
/// text file the manifest recorded equal to a base graph whose key is
2086 
/// `key`, the key the base has now, is not read either: equal keys mean
2087 
/// equal renderings, so it still equals the base. Touches no repository
2088 
/// state, so the walk runs it in parallel; the caller checks that a cached
2089 
/// blob is still in the store.
e7ddd552 Andy McCall ↶ 2090 
fn read_file_entry(
2091 
    rel: &str,
2092 
    path: &Path,
2093 
    meta: &fs::Metadata,
2094 
    cache: Option<&prompt::Manifest>,
1966f5db Andy McCall ↶ 2095 
    key: Option<[u8; 32]>,
e7ddd552 Andy McCall ↶ 2096 
) -> Result<FsEntry> {
2097 
    let exec = is_executable(meta);
8b276e01 Andy McCall ↶ 2098 
    let stat = Some((meta.len(), prompt::mtime_ns(meta)));
2099 
    let mut e = match stat_cached(rel, meta, cache) {
e7ddd552 Andy McCall ↶ 2100 
        Some(e) if e.blob.is_some() => FsEntry {
2101 
            blob: e.blob,
1966f5db Andy McCall ↶ 2102 
            content_hash: Some(e.hash),
cc7a0056 Andy McCall ↶ 2103 
            ..FsEntry::new(NodeKind::File, exec, vec![])
2104 
        },
1966f5db Andy McCall ↶ 2105 
        Some(e) if key.is_some() && e.graph == key => FsEntry {
2106 
            content_hash: Some(e.hash),
cc7a0056 Andy McCall ↶ 2107 
            unchanged: true,
1966f5db Andy McCall ↶ 2108 
            graph_key: e.graph,
cc7a0056 Andy McCall ↶ 2109 
            ..FsEntry::new(NodeKind::File, exec, vec![])
2110 
        },
2111 
        Some(e) => FsEntry {
1966f5db Andy McCall ↶ 2112 
            content_hash: Some(e.hash),
cc7a0056 Andy McCall ↶ 2113 
            ..FsEntry::new(NodeKind::File, exec, fs::read(path)?)
e7ddd552 Andy McCall ↶ 2114 
        },
2115 
        None => FsEntry::new(NodeKind::File, exec, fs::read(path)?),
8b276e01 Andy McCall ↶ 2116 
    };
2117 
    // The stat the manifest records: taken before the read, so a file that
2118 
    // changes meanwhile is read again next time.
2119 
    e.stat = stat;
2120 
    Ok(e)
e7ddd552 Andy McCall ↶ 2121 
}
f57bf670 Andy McCall ↶ 2122
2123 
/// Two maps side by side in key order: each key of either, with its value
2124 
/// in each. Linear, with no lookups, for maps of a whole tree.
2125 
pub(crate) fn join<'a, A, B>(
2126 
    a: &'a BTreeMap<String, A>,
2127 
    b: &'a BTreeMap<String, B>,
2128 
) -> impl Iterator<Item = (&'a String, Option<&'a A>, Option<&'a B>)> {
2129 
    let (mut a, mut b) = (a.iter().peekable(), b.iter().peekable());
2130 
    std::iter::from_fn(move || match (a.peek(), b.peek()) {
2131 
        (None, None) => None,
2132 
        (Some(_), None) => a.next().map(|(k, v)| (k, Some(v), None)),
2133 
        (None, Some(_)) => b.next().map(|(k, v)| (k, None, Some(v))),
2134 
        (Some((ka, _)), Some((kb, _))) => match ka.cmp(kb) {
2135 
            std::cmp::Ordering::Less => a.next().map(|(k, v)| (k, Some(v), None)),
2136 
            std::cmp::Ordering::Greater => b.next().map(|(k, v)| (k, None, Some(v))),
2137 
            std::cmp::Ordering::Equal => {
2138 
                let (k, va) = a.next()?;
2139 
                let (_, vb) = b.next()?;
2140 
                Some((k, Some(va), Some(vb)))
2141 
            }
2142 
        },
2143 
    })
2144 
}
2145
2146 
/// The entries of `a` whose keys `b` lacks, in key order: linear, with no
2147 
/// lookups.
2148 
pub(crate) fn missing_from<'a, A, B>(
2149 
    a: &'a BTreeMap<String, A>,
2150 
    b: &BTreeMap<String, B>,
2151 
) -> Vec<(&'a String, &'a A)> {
2152 
    let mut keys = b.keys().peekable();
2153 
    a.iter()
2154 
        .filter(|(k, _)| {
2155 
            while keys.next_if(|kb| *kb < *k).is_some() {}
2156 
            keys.peek() != Some(k)
2157 
        })
2158 
        .collect()
2159 
}