boxmaker/docs/plans/M5d2/11-loopd-heartbeat-failed-last.md

M5d-2 task 11: a failed heartbeat still advances last_heartbeat

Branch: m5d2. Check it: git branch --show-current prints m5d2 and git status --short is empty; otherwise stop. Never switch branch. Commit subject: loopd: a failed heartbeat still advances last_heartbeat Log row: the Task cell is M5d2/11-loopd-heartbeat-failed-last.

First action. Run this before any Read of crate source. Do not ls crates/loopd/tests/. Do not Read tests/support/, session.rs, turn.rs, compact.rs, jobs.rs, or docs/implementer-log.md (except the first 12 lines at the log step). The quoted block is the only edit.

cp docs/plans/M5d2/files/crates/loopd/tests/scheduler_heartbeat_failed.rs crates/loopd/tests/

Goal

After run_turn and finish_turn on the standing heartbeat session, always set last_heartbeat = Some(now) and push TickWork::Heartbeat, including when the outcome is Err (M5d-2 review finding 1; task 06's "The turn" fact). A failed pulse must not be due again on the next 1 s tick.

An unreadable prompt still does not update last_heartbeat. A busy skip still does not. Cron Finished / Failed is unchanged.

Every place that changes

Place	What happens there
crates/loopd/src/scheduler.rs	after the heartbeat turn, bookkeeping is unconditional (edit H1)
crates/loopd/tests/scheduler_heartbeat_failed.rs	new, given
everything else	no change

Files

• Copy, from docs/plans/M5d2/files/ (the same path under it): the new test crates/loopd/tests/scheduler_heartbeat_failed.rs.
• Modify: crates/loopd/src/scheduler.rs, docs/implementer-log.md.
• Do not touch: any other file. Do not edit crates/loopd/tests/scheduler_heartbeat.rs.

Facts you need

• H1. In heartbeat, the quoted block is found exactly once. Replace it with the after block. finish_turn still runs. drop(held) still runs. Then last_heartbeat and Heartbeat, with no if outcome.is_ok().
• Unreadable prompt / Busy. Those return paths stay as they are. They never reach H1.
• Reply::fixture("bad_request") is HTTP 400. It is not retried. The given test does not sleep (T27).

The edit (H1)

In crates/loopd/src/scheduler.rs, this block (exactly once):

        let text = format!("It is {}.\n\n{file}", now.to_rfc3339());
        let mut emit = |_event: &TurnEvent| {};
        let outcome = run_turn(&mut session, &runtime, &text, None, &mut emit);
        let outcome = compact::finish_turn(
            &mut session,
            &runtime,
            &*ctx.memory,
            &text,
            None,
            &mut emit,
            outcome,
        );
        if outcome.is_ok() {
            self.last_heartbeat = Some(now);
            work.push(TickWork::Heartbeat);
        }
        drop(held);

becomes:

        let text = format!("It is {}.\n\n{file}", now.to_rfc3339());
        let mut emit = |_event: &TurnEvent| {};
        let outcome = run_turn(&mut session, &runtime, &text, None, &mut emit);
        let _ = compact::finish_turn(
            &mut session,
            &runtime,
            &*ctx.memory,
            &text,
            None,
            &mut emit,
            outcome,
        );
        drop(held);
        self.last_heartbeat = Some(now);
        work.push(TickWork::Heartbeat);

Steps

• 1. Copy the given test.

  cp docs/plans/M5d2/files/crates/loopd/tests/scheduler_heartbeat_failed.rs crates/loopd/tests/
  

• 2. See it fail. cargo test -p loopd --test scheduler_heartbeat_failed, timeout 600000 ms. Expected: one test fails, a_failed_heartbeat_turn_still_advances_last_heartbeat, with left: [] and right: [Heartbeat]. Every other loopd test target is untouched. Do not open the test to find out why.

• 3. Make H1. The before block is found exactly once. cargo fmt --all. cargo check -p loopd prints no error and no warning.

• 4. See it pass. cargo test -p loopd --test scheduler_heartbeat_failed --test scheduler_heartbeat: every test passes, 1 in scheduler_heartbeat_failed, 6 in scheduler_heartbeat.

• 5. Run the gate. cargo fmt --all, then make gate, timeout 600000 ms. Last line gate: ok. Test count 1575 (1574 before, plus 1). After gate: ok, do not add up test result: lines.

• 6. Log and commit. Task cell M5d2/11-loopd-heartbeat-failed-last. Read only the first 12 lines of docs/implementer-log.md; insert the row under the header. Stage with git add crates/loopd/src/scheduler.rs crates/loopd/tests/scheduler_heartbeat_failed.rs docs/implementer-log.md Cargo.lock, then commit as AGENTS.md says.

Done when

• make gate prints gate: ok with 1575 tests.
• git diff HEAD~1 --stat lists only crates/loopd/src/scheduler.rs, crates/loopd/tests/scheduler_heartbeat_failed.rs and the log.

Stop and report if

• The branch check fails; the before block is not found exactly once; step 2 differs (a different test fails, or it passes); cargo check warns; a test in scheduler_heartbeat fails; the gate's last line is not gate: ok; you edit the unreadable-prompt path; you change cron Finished / Failed.

What the given tests pin

A due heartbeat whose inference returns HTTP 400 still pushes Heartbeat and is not due again 30 s later (every_s 60). The existing six heartbeat tests stay green: every_s 0, busy skip, unreadable prompt, and a successful second tick before every_s.