ci(shorebird): stream child stdout/stderr from shard_runner#144
Merged
eseidel merged 2 commits intoshorebird/devfrom May 8, 2026
Merged
ci(shorebird): stream child stdout/stderr from shard_runner#144eseidel merged 2 commits intoshorebird/devfrom
eseidel merged 2 commits intoshorebird/devfrom
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`runChecked` used `Process.run`, which buffers stdout/stderr in memory and prints nothing until the process exits — and on success, prints nothing at all. That hid 30+ minutes of ninja, cargo, and gclient output per shard from the GitHub Actions log; only the [Step] start / [Step] complete prints from the runner itself made it through. The legacy bash build scripts streamed naturally, so this is a regression the sharded runner introduced. Switch `runChecked` to `Process.start` with inheritStdio so output goes live to the parent's stdio. The error path no longer needs to echo captured output (it already streamed) — the exception just notes the exit code and description. Add `runCapturingStdout` for the one place that actually parses child output (`gsutil ls` in lib/gcs.dart). It captures stdout while still streaming stderr, so failures still appear in the log live. Tests: 32/32 pass; dart analyze clean.
bdero
approved these changes
May 8, 2026
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Summary
runCheckedusedProcess.run, which buffers stdout/stderr in memoryand only emits anything on a non-zero exit — and on success, nothing at
all. The result: 30+ minutes of
ninja,cargo, andgclientoutputper shard never reached the GitHub Actions log. Only the runner's own
[Step] starting/[Step] completeprints made it through, so ahealthy shard looked like a frozen one.
The legacy
mac_build.sh/linux_build.shscripts streamed naturally(plain bash invocations of
\$NINJA -C ...), so this was a regressionthe sharded runner introduced.
Change
runCheckednow usesProcess.startwithProcessStartMode.inheritStdio,so child stdout/stderr go live to the parent's stdio (and thus the CI
log). On failure the exception just notes the exit code — captured
output is no longer included because it already streamed.
runCapturingStdoutfor the one place that actually parses childoutput (
gsutil lsinlib/gcs.dart). It captures stdout whilestill streaming stderr.
lib/gcs.dartupdated to use it.Test plan
dart analyzecleandart test(32/32 pass)_build_engine; verify ninja[N/M]progress lines and cargo per-target output appear live in the
GHA log