test: run EVAL timeout tests under testing/synctest#128
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Wrap the context-deadline tests (TestContextTimeoutFiresOnTime, TestContextNoTimeout, the two future variants, TestTimeoutOnTryCatch) in synctest.Test so the time package uses a fake clock: deadlines fire deterministically (no wall-clock jitter) and instantly (no real wait). This lets TestTimeoutOnTryCatch drop back to a tight 500ms deadline — the value that was flaky under the real clock and which an earlier commit had widened to 2s to paper over the jitter. Verified 30x under full CPU load, all green, with and without -tags debugger. Also drops the redundant concurrent.Load setup in the future tests (newEnv already loads it). Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
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Summary
Wraps the EVAL context-deadline tests in
synctest.Test(Go 1.25+): inside the bubble thetimepackage uses a fake clock that only advances when every goroutine is durably blocked, so deadlines fire deterministically (no wall-clock jitter) and instantly (no real wait).Converted:
TestContextTimeoutFiresOnTime,TestContextNoTimeout,TestFutureContextTimeoutFiresOnTime,TestFutureContextNoTimeout,TestTimeoutOnTryCatch.The headline win:
TestTimeoutOnTryCatchgoes back to a tight 500ms deadline — the value that was flaky under the real clock, which an earlier commit had widened to 2s to mask the jitter. Under the fake clock thecatchhandler runs at zero fake time, so the timeout is caught deterministically. Also drops the redundantconcurrent.Loadsetup in the future tests (newEnvalready loads it), which was building an env the test then didn't use.Test plan
-tags debugger(the debugger build activates the EVAL hook path; synctest still works).🤖 Generated with Claude Code