fix: Compile no longer leaves Unity busy after finishing

[hatayama]

Summary

• uloop compile now recovers when Unity finishes compiling but the completion signal is missed.
• Follow-up commands such as get-logs no longer stay blocked behind a stale busy state.

User Impact

• Before this change, uloop compile could remain in progress indefinitely even after Unity had stopped compiling, and later commands could keep returning UNITY_SERVER_BUSY until the Editor was restarted.
• After this change, the compile request completes as indeterminate once Unity is no longer compiling and the finish signal still has not arrived, so agents can inspect logs or retry without restarting Unity.

Changes

• Watch the full compile lifecycle instead of only waiting for compile start.
• Preserve the existing compile-start timeout behavior while adding missed-finish recovery.
• Add focused EditMode coverage for missed completion, normal completion, and start-timeout paths.

Verification

• Packages/src/Cli~/dist/darwin-arm64/uloop compile --project-path "$(git rev-parse --show-toplevel)"
• Packages/src/Cli~/dist/darwin-arm64/uloop run-tests --test-mode EditMode --filter-type regex --filter-value ".*CompileLifecycleWatchdogTests.*" --project-path "$(git rev-parse --show-toplevel)"
• Packages/src/Cli~/dist/darwin-arm64/uloop compile --force-recompile --project-path "$(git rev-parse --show-toplevel)"
• Packages/src/Cli~/dist/darwin-arm64/uloop get-logs --project-path "$(git rev-parse --show-toplevel)"
• codex-review v3-beta --parallel-tests ...

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

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📥 Commits

Reviewing files that changed from the base of the PR and between cdc4c7f and 562d1b4.

📒 Files selected for processing (2)

• Assets/Tests/Editor/CompileLifecycleWatchdogTests.cs
• Packages/src/Editor/FirstPartyTools/Compile/CompileController.cs

🚧 Files skipped from review as they are similar to previous changes (2)

• Assets/Tests/Editor/CompileLifecycleWatchdogTests.cs
• Packages/src/Editor/FirstPartyTools/Compile/CompileController.cs

---

📝 Walkthrough

Walkthrough

Adds CompileLifecycleWatchdog (polling state machine) plus a new protocol constant, integrates it into CompileController to replace start-only polling, produces indeterminate results when finish callbacks are missed, and adds tests that validate start-timeout, missed-callback recovery, and fault propagation.

Changes

Compile Lifecycle Watchdog

Layer / File(s)	Summary
Timeout constant and watchdog state machine Packages/src/Editor/ToolContracts/UnityCliLoopConstants.cs, Packages/src/Editor/FirstPartyTools/Compile/CompileLifecycleWatchdog.cs	Adds COMPILE_FINISH_MISSED_CALLBACK_GRACE_MS = 500 and implements CompileLifecycleWatchdog with injected isEditorCompiling, isRequestCompleted, a poll-delay task, lifecycle callbacks, and WatchAsync that enforces start timeout, observes compile start, detects stopped-compiling → missed-completion after a grace window, and surfaces cancellation.
CompileController lifecycle integration Packages/src/Editor/FirstPartyTools/Compile/CompileController.cs	TryCompileAsync now starts WatchCompileLifecycleAsync (fire-and-forget). Adds watchdog wiring and fault handling, HandleCompileStoppedWithoutFinishEvent to abort with an indeterminate CompileResult, CreateIndeterminateCompileResult helper, and updates Cleanup() to reset _isCompiling and _isForceCompile.
Watchdog behavior tests Assets/Tests/Editor/CompileLifecycleWatchdogTests.cs	Adds CompileLifecycleWatchdogTests with async tests covering missed-callback recovery (grace window), no recovery when request completes after start, start-timeout when compile never starts, a test for polling task faults surfacing, and two private isCompiling suppliers (SequenceCompilationState, ConstantCompilationState).

Estimated code review effort

🎯 4 (Complex) | ⏱️ ~45 minutes

Possibly related PRs

• fix: Compile fails fast on asmdef and asmref import errors #1225: Modifies compile lifecycle/completion flow in CompileController.cs including cancellation/cleanup behavior and console-error asmdef/asmref handling.

🚥 Pre-merge checks | ✅ 4 | ❌ 1

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Docstring Coverage	⚠️ Warning	Docstring coverage is 11.54% which is insufficient. The required threshold is 80.00%.	Write docstrings for the functions missing them to satisfy the coverage threshold.

✅ Passed checks (4 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title clearly and specifically summarizes the main change: fixing a bug where compilation no longer leaves Unity in a busy state after finishing, which aligns directly with the PR's core objective of handling missed completion callbacks.
Description check	✅ Passed	The description is directly related to the changeset, clearly explaining the problem (missed completion signals leaving Unity busy), the solution (full lifecycle watching with missed-finish recovery), and user impact.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

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✨ Finishing Touches

📝 Generate docstrings

• Create stacked PR
• Commit on current branch

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch feature/hatayama/fix-compile-hang-recovery

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[coderabbitai]

Actionable comments posted: 1

🤖 Prompt for all review comments with AI agents

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

Inline comments:
In `@Packages/src/Editor/FirstPartyTools/Compile/CompileController.cs`:
- Line 165: The call in CompileController.cs currently fire-and-forgets
WatchCompileLifecycleAsync(ct), which lets CompileLifecycleWatchdog.WatchAsync
fault silently and prevents watchdog callbacks (e.g., AbortCompile*,
compilationFinished) from running; instead, capture the returned Task from
WatchCompileLifecycleAsync(ct) and attach an observed continuation (or await it
on a safe background Task) that catches exceptions, logs the error, and invokes
the appropriate abort/cleanup path (e.g., call the AbortCompile* methods or
signal compilationFinished) so faults don't leave the controller waiting;
reference WatchCompileLifecycleAsync, CompileLifecycleWatchdog.WatchAsync,
AbortCompile* and compilationFinished when adding this try/catch/continuation
handling.

🪄 Autofix (Beta)

Fix all unresolved CodeRabbit comments on this PR:

• Push a commit to this branch (recommended)
• Create a new PR with the fixes

---

ℹ️ Review info

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Configuration used: Path: .coderabbit.yaml

Review profile: CHILL

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📥 Commits

Reviewing files that changed from the base of the PR and between ba735f1 and d775c18.

⛔ Files ignored due to path filters (2)

• Assets/Tests/Editor/CompileLifecycleWatchdogTests.cs.meta is excluded by none and included by none
• Packages/src/Editor/FirstPartyTools/Compile/CompileLifecycleWatchdog.cs.meta is excluded by none and included by none

📒 Files selected for processing (4)

• Assets/Tests/Editor/CompileLifecycleWatchdogTests.cs
• Packages/src/Editor/FirstPartyTools/Compile/CompileController.cs
• Packages/src/Editor/FirstPartyTools/Compile/CompileLifecycleWatchdog.cs
• Packages/src/Editor/ToolContracts/UnityCliLoopConstants.cs

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2 issues found across 6 files

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Actionable comments posted: 0

[cubic-dev-ai]

1 issue found across 2 files (changes from recent commits).

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[coderabbitai]

Actionable comments posted: 0