An issue's references: no line through the chips, each change once (closes #318) 8bb7baeb4557

- **An issue's references: no line through the chips, each change once (#318):** an opened "referenced by N changes" box drew the proposal timeline's vertical rule through its first column (the events shared its class); and a change was recorded again for every bookmark it was pushed on, and for every mention in its message, so one change filled several chips. Now one reference per change per issue or proposal, and the page shows each change once, including those recorded before.

/// Whether change `hash` (its short form) already references it (#318):

/// a change is recorded once, whichever bookmarks it is pushed on.

pub async fn referenced_by(pool: &Pool, issue_id: i64, hash: &str) -> sqlx::Result<bool> {

    let n: i64 = sqlx::query_scalar(

        "SELECT COUNT(*) FROM issue_events WHERE issue_id = $1 AND event = 'referenced by change' AND (detail = $2 OR detail LIKE $3)",

    )

    .bind(issue_id)

    .bind(hash)

    .bind(format!("{hash} %"))

    .fetch_one(pool)

    .await?;

    Ok(n > 0)

}

/// Whether change `hash` (its short form) already references it (#318):

/// a change is recorded once, whichever bookmarks it is pushed on.

pub async fn referenced_by(pool: &Pool, proposal_id: i64, hash: &str) -> sqlx::Result<bool> {

    let n: i64 = sqlx::query_scalar(

        "SELECT COUNT(*) FROM proposal_events WHERE proposal_id = $1 AND event = 'referenced by change' AND (detail = $2 OR detail LIKE $3)",

    )

    .bind(proposal_id)

    .bind(hash)

    .bind(format!("{hash} %"))

    .fetch_one(pool)

    .await?;

    Ok(n > 0)

}

    // Each change once, at its first reference (#318): before that was

    // recorded once, a change was recorded again for every bookmark.

    let mut seen = std::collections::HashSet::new();

                if !seen.insert(e.detail.split(' ').next().unwrap_or("").to_string()) {

                    continue;

                }

        let short = &hash[..12.min(hash.len())];

        let detail = format!("{short} on {bookmark}");

        // Once per change (#318): not again for a second mention, nor when

        // the change is pushed on another bookmark or landed.

        let mut named = render::refs::references(message);

        named.sort_unstable();

        named.dedup();

        for n in named {

                    if !idb::referenced_by(&app.db, i.id, short).await.unwrap_or(false) {

                        idb::add_event(&app.db, i.id, actor, "referenced by change", &detail).await.ok();

                    }

                    if !db::proposals::referenced_by(&app.db, p.id, short).await.unwrap_or(false) {

                        db::proposals::add_event(&app.db, p.id, actor, "referenced by change", &detail).await.ok();

                    }

    // #318: the same change pushed on another bookmark is no new reference.

    client.bookmark_create("again", None).unwrap();

    assert!(client.push_bookmark("origin", "again", false).unwrap().iter().all(|r| r.ok));

    tokio::time::sleep(std::time::Duration::from_millis(1500)).await;

    let recorded: i64 = sqlx::query_scalar("SELECT COUNT(*) FROM issue_events WHERE event = 'referenced by change' AND detail LIKE $1")

        .bind(format!("{short} %"))

        .fetch_one(&app.db)

        .await

        .unwrap();

    assert_eq!(recorded, 1, "once per change, whichever bookmarks it is on");

    // One recorded again for another bookmark before #318: shown once.

    sqlx::query("INSERT INTO issue_events (issue_id, at_ms, actor, event, detail) VALUES ($1, $2, 'andy', 'referenced by change', $3)")

        .bind(issue1.id)

        .bind(day + 4_000)

        .bind(format!("{:012x} on develop", 0xabc000))

        .execute(&app.db)

        .await

        .unwrap();

    assert_eq!(one.matches(&format!("change/{:012x}\"", 0xabc000)).count(), 1, "each change once");

    assert!(!one.contains("mute timeline"), "the events have no rule of their own (#318)");

    <p class="small mute tl-event">{{ e.actor }} {{ e.event }}{% if e.event.ends_with("by change") && !e.detail.is_empty() %}{% let hash = e.detail.split(' ').next().unwrap_or("") %} <a href="{{ repo.url }}/change/{{ hash }}"><code>{{ hash }}</code></a>{{ e.detail[hash.len()..] }}{% else if !e.detail.is_empty() %} {{ e.detail }}{% endif %} · <time title="{{ e.at_ms|when_i }}">{{ e.at_ms|ago_i }}</time></p>

    <details class="small mute tl-event refs-day"{% if *open %} open{% endif %}><summary>referenced by {{ events.len() }} changes on {{ day }}</summary>

/* An issue's events and its references by day: indented lines, without the

   proposal timeline's rule (.timeline::before drew one through the chips). */

.tl-event { margin: 0 0 8px 14px; }