Files
sproutclaw/packages/coding-agent/test/suite/regressions/5303-bash-output-truncation.test.ts

80 lines
3.0 KiB
TypeScript

import type { ChildProcessByStdio } from "node:child_process";
import type { Readable } from "node:stream";
import { afterEach, describe, expect, it } from "vitest";
import { spawnProcess, waitForChildProcess } from "../../../src/utils/child-process.ts";
/**
* Regression test for https://github.com/earendil-works/pi/issues/5303
*
* waitForChildProcess armed a fixed 100ms timer on `exit` and destroyed the
* stdio streams when it fired. When a short-lived detached descendant kept the
* stdout pipe open, `close` never fired, so that timer was the only thing that
* resolved the wait, and any output written more than 100ms after exit was
* binned. In practice every git commit whose pre-commit hook runs lint-staged
* came back truncated mid-listr2 output, read by the model as a hang.
*
* The fix re-arms the grace on each chunk, so an actively writing pipe keeps us
* reading while a genuinely idle held-open handle still releases after the
* grace elapses. Both behaviours are covered below.
*/
describe.skipIf(process.platform === "win32")("issue #5303 bash output truncation past exit", () => {
let child: ChildProcessByStdio<null, Readable, Readable> | undefined;
afterEach(() => {
if (child?.pid) {
try {
process.kill(-child.pid, "SIGKILL");
} catch {
// Already gone.
}
}
child = undefined;
});
it("captures output emitted after exit while a detached child holds stdout open", async () => {
// The shell exits immediately, but a backgrounded subshell keeps the stdout
// pipe open and emits ticks every 50ms, the last well past the 100ms grace.
const command = 'printf "HEAD\\n"; ( for i in 1 2 3 4 5 6; do sleep 0.05; printf "TICK$i\\n"; done ) &';
child = spawnProcess("/bin/sh", ["-c", command], {
stdio: ["ignore", "pipe", "pipe"],
detached: true,
}) as ChildProcessByStdio<null, Readable, Readable>;
let output = "";
child.stdout.on("data", (chunk: Buffer) => {
output += chunk.toString();
});
const exitCode = await waitForChildProcess(child);
expect(exitCode).toBe(0);
expect(output).toContain("HEAD");
expect(output).toContain("TICK6");
});
it("resolves promptly when a detached child holds stdout open but stays quiet", async () => {
// The shell exits, but a backgrounded sleeper inherits the stdout pipe and
// keeps it open for a long time without writing. `close` never fires, so we
// must still release via the idle grace rather than hang on the open handle.
const command = 'printf "DONE\\n"; ( sleep 30 ) &';
child = spawnProcess("/bin/sh", ["-c", command], {
stdio: ["ignore", "pipe", "pipe"],
detached: true,
}) as ChildProcessByStdio<null, Readable, Readable>;
let output = "";
child.stdout.on("data", (chunk: Buffer) => {
output += chunk.toString();
});
const start = Date.now();
const exitCode = await waitForChildProcess(child);
const elapsed = Date.now() - start;
expect(exitCode).toBe(0);
expect(output).toContain("DONE");
// Must not wait for the 30s sleeper; the idle grace releases us in well under a second.
expect(elapsed).toBeLessThan(2000);
});
});