fix: skip stdin read when positional message provided#935
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`!process.stdin.isTTY` alone is too broad — it matches not just "someone piped input in" but also "the parent process inherited stdin from somewhere upstream and never closed its end." In the second case, `Bun.stdin.text()` waits forever for an EOF that never arrives. The process sits at 0% CPU with no session created, no log activity, no error — a silent hang. This surfaces in every subprocess invocation pattern that passes a positional message and inherits stdin: Claude Code's Bash tool, Python `subprocess.run(..., stdin=None)`, CI runners, plugin hosts that don't pin stdin to `/dev/null`. Downstream callers have been working around it with `stdio: "ignore"` on spawn (see e.g. altimate-opencode-plugin `plugins/altimate-code/index.ts:28`), but anything that forgets to do that still hits the wedge. Fix: only read stdin when no positional `message` was provided. Matches conventional CLI semantics (positional overrides stdin) and unblocks every subprocess caller. Pipe-only invocations without a positional arg continue to work unchanged. Closes #934
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📝 WalkthroughWalkthroughThe run command's stdin handling is now conditional: it reads from stdin only when the process is non-TTY and no positional message was provided, preventing hangs on inherited stdin file descriptors that never close. Added comments explain the guard behavior. ChangesConditional stdin read guard
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❌ Tests — Failures DetectedTypeScript — 15 failure(s)
Next StepPlease address the failing cases above and re-run verification. cc @sahrizvi |
2 participants
Closes #934
Summary
altimate-code run "<task>"hangs at 0% CPU forever when invoked as a subprocess from a context that inherits stdin without closing it (Claude Code's Bash tool, Pythonsubprocess.run, CI, plugin hosts that don't pin stdin to/dev/null). The cause is an over-broad guard atpackages/opencode/src/cli/cmd/run.ts:433:!process.stdin.isTTYmatches not just "someone piped input in" (the intended case) but also "stdin was inherited from a non-TTY parent that hasn't closed it" (the wedge case). In the second caseBun.stdin.text()waits forever for an EOF that never arrives.Fix
Only read stdin when no positional
messagewas provided:This matches conventional CLI semantics (positional argument overrides stdin —
tool "explicit arg"doesn't try to consume stdin;echo "task" | toolstill does) and unblocks every subprocess caller that passes a positional message, which is the dominant pattern in agent / skill / plugin invocations ofaltimate-code run.Downstream context
Downstream consumers have been working around the wedge by spawning altimate-code with
stdio: ["ignore", "pipe", "pipe"]— see altimate-opencode-pluginplugins/altimate-code/index.ts:28and its lineage comment at lines 177-182 explicitly referencing this bug. That workaround is fine for the plugin itself but doesn't protect any other caller (Claude Code's Bash tool, ad-hoc CI scripts, future plugins that forget). This PR is the proper fix at the source.Test plan
altimate-code-preview run "say hi" --yolo(built from a worktree with the same patch) returns in ~1.3s instead of hanging — has been running this way for ~9 days against real workloads.altimate-code run "say hi and exit" --yolofrom a Pythonsubprocess.run(..., stdin=None)parent — expect completion in seconds, not a hang.echo "hello task" | altimate-code run --yolostill reads stdin (no positional arg → guard's second conditionmessage.trim().length === 0is true → stdin is consumed).No new unit test added — there's no existing test for
cmd/run.ts, and the function is a CLI entry point that's awkward to mock at this granularity (needs spies onprocess.stdin.isTTYandBun.stdin.text()plus the surrounding setup). Happy to add one if reviewers prefer; the conditional itself is small enough that the diff is largely self-documenting.Risk
Very low. The change tightens an existing guard — any caller that should be reading stdin (no positional message) still does; the only behavior change is for callers that both pass a positional message and inherit non-TTY stdin, which is exactly the population that has been silently hanging.
Links
03-issues-and-fixes.mdIssue chore(deps): Bump @modelcontextprotocol/sdk from 1.25.2 to 1.26.0 in /packages/altimate-code #2 (in the plugin-skill-experiments deliverable)altimate-opencode-plugin/plugins/altimate-code/index.ts:28Summary by cubic
Prevented
altimate-code runfrom hanging by only reading stdin when no positional message is provided. Subprocess calls with inherited non‑TTY stdin now complete as expected while pipe-based input still works.messageis empty, updating guard inpackages/opencode/src/cli/cmd/run.ts.Bun.stdin.text()when called from tools like Pythonsubprocess.run, CI, or plugin hosts.echo "task" | altimate-code runstill reads stdin;altimate-code run "task"skips stdin.Written for commit a387257. Summary will update on new commits.
Summary by CodeRabbit