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📝 WalkthroughWalkthroughAdds a Stdio middleware context API and wires it into process creation; refactors POSIX and Win32 process factories from resource-based producers to generator-based factories that evaluate middleware in an evalScope, forward per-chunk stdio through the Stdio API, and expose per-process Changes
Sequence Diagram(s)mermaid Test->>+Proc: call createProcess(command, options) Estimated code review effort🎯 4 (Complex) | ⏱️ ~50 minutes Possibly related PRs
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Important Pre-merge checks failedPlease resolve all errors before merging. Addressing warnings is optional. ❌ Failed checks (1 error, 1 warning)
✅ Passed checks (2 passed)
✨ Finishing Touches📝 Generate docstrings
🧪 Generate unit tests (beta)
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Actionable comments posted: 7
🤖 Prompt for all review comments with AI agents
Verify each finding against the current code and only fix it if needed.
Inline comments:
In `@context-api/mod.ts`:
- Around line 62-63: Add an object constraint to the createApi generic and
remove the unsafe cast: change the function signature to declare A extends
object (i.e., createApi<A extends object>(...)) so null/undefined can't be
passed, and update the fields initialization to call Object.keys(handler)
without casting handler to object (you may still assert the result to (keyof
A)[] for typing). This touches the createApi function and the fields variable
where Object.keys(handler as object) is currently used.
In `@process/package.json`:
- Around line 41-43: The package.json's version field needs a semantic bump
because source/API changed: update the "version" value in process/package.json
(the package's top-level "version" field) from 0.7.4 to 0.8.0 (or appropriate
minor increment) and commit that change so the package version reflects the new
functionality and satisfies the repository's version-bump policy.
In `@process/README.md`:
- Around line 73-81: The example middleware is broken: the generator handler
stdout is missing the line parameter and the code writes to the local Process
object instead of Node's stdio. Update the handlers on process.around so they
accept the line argument (e.g., function* stdout(line) { ... } and function*
stderr(line) { ... }) and write to Node's global stdio (use
global.process.stdout.write(line) and global.process.stderr.write(line) or
otherwise reference the Node process object rather than the local variable) so
the example executes correctly; apply these changes to the stdout and stderr
handlers shown in the snippet.
In `@process/src/exec/posix.ts`:
- Around line 82-86: The stderr pump is calling stdioApi.operations.stdout and
thus bypassing the stderr middleware; update the generator started by spawn (the
block that awaits io.stderr.next()) to forward bytes to
stdioApi.operations.stderr instead of stdioApi.operations.stdout and ensure it
still calls stderr.send(next.value) so the stderr middleware and downstream
consumers receive the correct stderr bytes (refer to io.stderr.next,
stdioApi.operations.stdout → replace with stdioApi.operations.stderr, and
stderr.send).
In `@process/src/exec/win32.ts`:
- Around line 184-186: The returned object is exposing stdioApi.around unbound
so callers mutate the wrong context; bind stdioApi.around to evalScope before
returning so proc.around() runs in the same scope as
stdioApi.operations.stdout/stderr. Update the return to use the bound function
(e.g. const around = stdioApi.around.bind(evalScope) and return around as the
around property) referencing stdioApi.around and evalScope in the same scope
where pid is set.
- Around line 177-180: The current condition uses !childProcess.exitCode which
treats exitCode 0 as false and may erroneously force-kill a cleanly exited
process; change the guard to explicitly check childProcess.exitCode === null
before calling killTree(pid) so the force-kill path only runs while the child is
still running (update the conditional that references pid and
childProcess.exitCode in the win32.ts block that calls killTree).
In `@process/test/exec.test.ts`:
- Around line 306-340: Tests under the "io api" describe block are
non-deterministic because stdout and stderr are merged into one array and for
the inline variant the middleware is attached after the child has started; fix
by capturing stdout and stderr into separate buffers (e.g., stdoutArr and
stderrArr), assert each with join("") rather than relying on raw chunk
boundaries, and ensure you register the around middleware before spawning the
process (use stdioApi.around or attach proc.around prior to calling exec/spawn)
so the handlers see all output; update both the "allows redirecting stdio to
array" and "allows redirecting stdio inline" tests to follow this pattern and
use proc.expect() only after capturing is guaranteed.
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- Create a new PR with the fixes
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context-api/mod.tsprocess/README.mdprocess/package.jsonprocess/src/api.tsprocess/src/exec.tsprocess/src/exec/error.tsprocess/src/exec/posix.tsprocess/src/exec/types.tsprocess/src/exec/win32.tsprocess/test/exec.test.tsprocess/tsconfig.json
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| yield* process.around({ | ||
| *stdout() { | ||
| // it does this by default | ||
| process.stdout.write(line); | ||
| }, | ||
| *stderr(line) { | ||
| // it does this by default | ||
| process.stderr.write(line); | ||
| }, |
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Fix the middleware example: line is undefined and stream target is incorrect.
stdout() is missing the line arg, and process.stdout.write(...) refers to the local Process object, not Node’s writable stdio. The sample currently won’t execute as documented.
Suggested doc fix
await main(function* () {
- let process = yield* exec("npm install");
+ let proc = yield* exec("npm install");
- yield* process.around({
- *stdout() {
+ yield* proc.around({
+ *stdout(line) {
// it does this by default
- process.stdout.write(line);
+ globalThis.process.stdout.write(line);
},
*stderr(line) {
// it does this by default
- process.stderr.write(line);
+ globalThis.process.stderr.write(line);
},
});
// Wait for the process to complete
- yield* process.expect();
+ yield* proc.expect();
});📝 Committable suggestion
‼️ IMPORTANT
Carefully review the code before committing. Ensure that it accurately replaces the highlighted code, contains no missing lines, and has no issues with indentation. Thoroughly test & benchmark the code to ensure it meets the requirements.
Suggested change
| yield* process.around({ | |
| *stdout() { | |
| // it does this by default | |
| process.stdout.write(line); | |
| }, | |
| *stderr(line) { | |
| // it does this by default | |
| process.stderr.write(line); | |
| }, | |
| await main(function* () { | |
| let proc = yield* exec("npm install"); | |
| yield* proc.around({ | |
| *stdout(line) { | |
| // it does this by default | |
| globalThis.process.stdout.write(line); | |
| }, | |
| *stderr(line) { | |
| // it does this by default | |
| globalThis.process.stderr.write(line); | |
| }, | |
| }); | |
| // Wait for the process to complete | |
| yield* proc.expect(); | |
| }); |
🤖 Prompt for AI Agents
Verify each finding against the current code and only fix it if needed.
In `@process/README.md` around lines 73 - 81, The example middleware is broken:
the generator handler stdout is missing the line parameter and the code writes
to the local Process object instead of Node's stdio. Update the handlers on
process.around so they accept the line argument (e.g., function* stdout(line) {
... } and function* stderr(line) { ... }) and write to Node's global stdio (use
global.process.stdout.write(line) and global.process.stderr.write(line) or
otherwise reference the Node process object rather than the local variable) so
the example executes correctly; apply these changes to the stdout and stderr
handlers shown in the snippet.
There was a problem hiding this comment.
♻️ Duplicate comments (1)
process/package.json (1)
4-4:⚠️ Potential issue | 🟠 MajorVersion bump is required for this feature change.
The version field remains at
0.7.4despite this PR adding new functionality (process logging middleware and new dependencies). A semantic version bump is required.As per coding guidelines: ".policies/version-bump.md: If PR changes package source (non-test), include a semantic version bump in that package's
package.json."🤖 Prompt for AI Agents
Verify each finding against the current code and only fix it if needed. In `@process/package.json` at line 4, The package.json "version" field was not updated for this PR's new functionality; open the package.json and update the "version" value (the "version" key) to the next semantic version (e.g., bump 0.7.4 → 0.8.0 for a minor feature addition) so the package reflects the change and complies with .policies/version-bump.md; commit the updated package.json with the bumped version.
🤖 Prompt for all review comments with AI agents
Verify each finding against the current code and only fix it if needed.
Duplicate comments:
In `@process/package.json`:
- Line 4: The package.json "version" field was not updated for this PR's new
functionality; open the package.json and update the "version" value (the
"version" key) to the next semantic version (e.g., bump 0.7.4 → 0.8.0 for a
minor feature addition) so the package reflects the change and complies with
.policies/version-bump.md; commit the updated package.json with the bumped
version.
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♻️ Duplicate comments (1)
process/test/exec.test.ts (1)
307-323:⚠️ Potential issue | 🟠 Major
io apiassertions are still nondeterministic and currently failing CI.Line 322 and Line 340 assert exact merged stdout/stderr chunk order, which is not stable. Also, in Line 328-338 the inline middleware is attached after spawn, so early writes can race.
Proposed stabilization (assert per-stream content, not merged ordering)
- it("allows redirecting stdio to array", function* () { - let output: string[] = []; + it("allows redirecting stdio to array", function* () { + let stdout: string[] = []; + let stderr: string[] = []; yield* stdioApi.around({ *stdout([bytes]) { - output.push(bytes.toString()); + stdout.push(bytes.toString()); }, *stderr([bytes]) { - output.push(bytes.toString()); + stderr.push(bytes.toString()); }, }); let proc = yield* exec("node './fixtures/hello-world.js'", { cwd: import.meta.dirname, }); yield* proc.expect(); - expect(output).toEqual(["hello\n", "world\n", "boom\n"]); + expect(stdout.join("")).toEqual("hello\nworld\n"); + expect(stderr.join("")).toEqual("boom\n"); }); it("allows redirecting stdio inline", function* () { - let output: string[] = []; + let stdout: string[] = []; + let stderr: string[] = []; let proc = yield* exec("node './fixtures/hello-world.js'", { cwd: import.meta.dirname, }); yield* proc.around({ *stdout([bytes]) { - output.push(bytes.toString().trim()); + stdout.push(bytes.toString()); }, *stderr([bytes]) { - output.push(bytes.toString().trim()); + stderr.push(bytes.toString()); }, }); yield* proc.expect(); - expect(output).toEqual(["hello", "world", "boom"]); + expect(stdout.join("")).toContain("hello"); + expect(stdout.join("")).toContain("world"); + expect(stderr.join("")).toContain("boom"); });As per coding guidelines: ".policies/deterministic-tests.md - Assert on lifecycle invariants, not timing."
Also applies to: 325-340
🤖 Prompt for AI Agents
Verify each finding against the current code and only fix it if needed. In `@process/test/exec.test.ts` around lines 307 - 323, The test is nondeterministic because stdio middleware is attached after the child is spawned and it asserts merged stdout/stderr chunk ordering; move the stdioApi.around call to wrap/attach before calling exec so no early writes are missed (reference stdioApi.around and exec/ proc.expect), and change assertions to validate per-stream content (collect stdout chunks and stderr chunks separately inside the stdout/ stderr handlers) and assert each stream's concatenated/ordered content independently rather than relying on interleaved merged ordering.
🤖 Prompt for all review comments with AI agents
Verify each finding against the current code and only fix it if needed.
Duplicate comments:
In `@process/test/exec.test.ts`:
- Around line 307-323: The test is nondeterministic because stdio middleware is
attached after the child is spawned and it asserts merged stdout/stderr chunk
ordering; move the stdioApi.around call to wrap/attach before calling exec so no
early writes are missed (reference stdioApi.around and exec/ proc.expect), and
change assertions to validate per-stream content (collect stdout chunks and
stderr chunks separately inside the stdout/ stderr handlers) and assert each
stream's concatenated/ordered content independently rather than relying on
interleaved merged ordering.
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process/test/exec.test.ts (1)
306-342:⚠️ Potential issue | 🔴 CriticalFix the flaky
io apitests – chunk boundaries are non-deterministic.The pipeline failures confirm the issue: expecting
["hello", "world", "boom"]but receiving["hello\nworld", "boom"]. The tests assume eachconsole.log()produces a separate chunk, but OS buffering can batch multiple lines into a single chunk. Additionally, the "inline" variant registersproc.around()after the process has started, risking missed output.Recommended fixes:
- Capture raw bytes without per-chunk trimming
- Join all captured output at the end, then split by newlines for comparison
- Keep stdout and stderr in separate arrays to avoid interleaving ambiguity
- For the inline test, use the streaming-capture approach or accept that exact ordering of stdout vs stderr may vary
🐛 Proposed fix
describe("io api", () => { it("allows redirecting stdio to array", function* () { - let output: string[] = []; + let stdoutChunks: Buffer[] = []; + let stderrChunks: Buffer[] = []; yield* stdioApi.around({ *stdout([bytes]) { - output.push(bytes.toString().trim()); + stdoutChunks.push(bytes); }, *stderr([bytes]) { - output.push(bytes.toString().trim()); + stderrChunks.push(bytes); }, }); let proc = yield* exec("node './fixtures/hello-world.js'", { cwd: import.meta.dirname, }); yield* proc.expect(); - expect(output).toEqual(["hello", "world", "boom"]); + + const stdout = Buffer.concat(stdoutChunks).toString(); + const stderr = Buffer.concat(stderrChunks).toString(); + expect(stdout).toEqual("hello\nworld\n"); + expect(stderr).toEqual("boom\n"); }); it("allows redirecting stdio inline", function* () { - let output: string[] = []; + let stdoutChunks: Buffer[] = []; + let stderrChunks: Buffer[] = []; let proc = yield* exec("node './fixtures/hello-world.js'", { cwd: import.meta.dirname, }); yield* proc.around({ *stdout([bytes]) { - output.push(bytes.toString().trim()); + stdoutChunks.push(bytes); }, *stderr([bytes]) { - output.push(bytes.toString().trim()); + stderrChunks.push(bytes); }, }); yield* proc.expect(); - expect(output).toEqual(["hello", "world", "boom"]); + + const stdout = Buffer.concat(stdoutChunks).toString(); + const stderr = Buffer.concat(stderrChunks).toString(); + expect(stdout).toEqual("hello\nworld\n"); + expect(stderr).toEqual("boom\n"); }); });🤖 Prompt for AI Agents
Verify each finding against the current code and only fix it if needed. In `@process/test/exec.test.ts` around lines 306 - 342, The io tests assume per-console-line chunks but buffering can merge lines and the inline test can miss early output; update both tests (the stdioApi.around and proc.around usages around exec/ proc.expect) to collect raw bytes into separate stdout and stderr arrays (do not trim per-chunk), then after yield* proc.expect() join each array into a single string and split on '\n' to produce lines for assertion; for the inline variant ensure you attach capture via proc.around as early as possible (or use stdioApi.around to wrap the exec call) so no output is missed, and assert on the split lines rather than per-chunk values.
🤖 Prompt for all review comments with AI agents
Verify each finding against the current code and only fix it if needed.
Duplicate comments:
In `@process/test/exec.test.ts`:
- Around line 306-342: The io tests assume per-console-line chunks but buffering
can merge lines and the inline test can miss early output; update both tests
(the stdioApi.around and proc.around usages around exec/ proc.expect) to collect
raw bytes into separate stdout and stderr arrays (do not trim per-chunk), then
after yield* proc.expect() join each array into a single string and split on
'\n' to produce lines for assertion; for the inline variant ensure you attach
capture via proc.around as early as possible (or use stdioApi.around to wrap the
exec call) so no output is missed, and assert on the split lines rather than
per-chunk values.
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♻️ Duplicate comments (2)
process/test/exec.test.ts (2)
325-341:⚠️ Potential issue | 🔴 CriticalRace condition: middleware registered after process spawns.
proc.around()is called afterexec()has already spawned the child process. Output may be emitted before the handlers are installed, causing missed chunks and non-deterministic test failures.This has the same
Uint8Array[].toString()assertion bug as the previous test.🔧 Proposed fix: register middleware before awaiting output
If
proc.aroundmust be used inline, consider whether the API should support registering handlers viaexec()options instead, or document thatproc.aroundmust be called before anyyield*that consumes streams.it("allows redirecting stdio inline", function* () { - let output: Uint8Array[] = []; + let stdoutChunks: Uint8Array[] = []; + let stderrChunks: Uint8Array[] = []; let proc = yield* exec("node './fixtures/hello-world.js'", { cwd: import.meta.dirname, }); + // Register middleware immediately after spawn, before consuming any output yield* proc.around({ *stdout([bytes]) { - output.push(bytes); + stdoutChunks.push(bytes); }, *stderr([bytes]) { - output.push(bytes); + stderrChunks.push(bytes); }, }); yield* proc.expect(); - expect(output.toString()).toEqual("hello\nworld\nboom\n"); + + const decoder = new TextDecoder(); + const stdout = stdoutChunks.map((c) => decoder.decode(c)).join(""); + const stderr = stderrChunks.map((c) => decoder.decode(c)).join(""); + + expect(stdout).toEqual("hello\nworld\n"); + expect(stderr).toEqual("boom\n"); });🤖 Prompt for AI Agents
Verify each finding against the current code and only fix it if needed. In `@process/test/exec.test.ts` around lines 325 - 341, The test registers proc.around handlers after calling exec("...") which spawns the child and can miss early stdout/stderr chunks; move the around registration so handlers are installed before the child can emit output (e.g., change the flow to register proc.around immediately after creating the proc or use an exec option to pass stdout/stderr handlers), and also fix the assertion by converting the concatenated Uint8Array[] into a string properly instead of calling Uint8Array[].toString(); update references to exec, proc.around, and proc.expect accordingly.
306-323:⚠️ Potential issue | 🔴 Critical
Uint8Array[].toString()produces comma-separated byte values, not decoded text.Calling
.toString()on an array ofUint8Arrayyields"104,101,108,108,111,10"rather than"hello\nworld\nboom\n". This assertion will fail immediately when the test runs.Additionally, merging stdout and stderr into the same array prevents verifying that each stream is correctly routed to its handler—a critical validation point since stream routing bugs can easily be missed with this approach.
🔧 Proposed fix: decode chunks and capture streams separately
describe("io api", () => { it("allows redirecting stdio to array", function* () { - let output: Uint8Array[] = []; + let stdoutChunks: Uint8Array[] = []; + let stderrChunks: Uint8Array[] = []; yield* stdioApi.around({ *stdout([bytes]) { - output.push(bytes); + stdoutChunks.push(bytes); }, *stderr([bytes]) { - output.push(bytes); + stderrChunks.push(bytes); }, }); let proc = yield* exec("node './fixtures/hello-world.js'", { cwd: import.meta.dirname, }); yield* proc.expect(); - expect(output.toString()).toEqual("hello\nworld\nboom\n"); + + const decoder = new TextDecoder(); + const stdout = stdoutChunks.map((c) => decoder.decode(c)).join(""); + const stderr = stderrChunks.map((c) => decoder.decode(c)).join(""); + + expect(stdout).toEqual("hello\nworld\n"); + expect(stderr).toEqual("boom\n"); });🤖 Prompt for AI Agents
Verify each finding against the current code and only fix it if needed. In `@process/test/exec.test.ts` around lines 306 - 323, The test is incorrectly calling .toString() on an array of Uint8Array and conflating stdout/stderr into one array; update the stdioApi.around handlers in the test (the generator callbacks passed to stdioApi.around and the local variable currently named output) to collect stdout and stderr separately (e.g., stdoutChunks and stderrChunks), decode each Uint8Array chunk with a TextDecoder (or Buffer.from(...).toString()) before pushing, then after proc.expect() join the decoded chunks and assert stdout and stderr strings individually against the expected values; keep references to stdioApi.around, the handler generator names (*stdout, *stderr), exec and proc.expect to locate where to change.
🤖 Prompt for all review comments with AI agents
Verify each finding against the current code and only fix it if needed.
Inline comments:
In `@process/test/exec.test.ts`:
- Around line 306-342: Change the stderr routing in process/src/exec/posix.ts so
that stderr chunks are dispatched to stdioApi.operations.stderr(...) instead of
stdioApi.operations.stdout(...); locate the loop that reads the child's stderr
(the place currently calling stdioApi.operations.stdout(next.value)) and call
stdioApi.operations.stderr(next.value) there. Also update the tests in
process/test/exec.test.ts ("io api") to collect stdout and stderr into separate
buffers (e.g., stdoutBuf and stderrBuf) and assert each buffer's contents
independently after exec/expect so the *stderr() handler (and its invocation via
proc.around / stdioApi.around) is verified.
---
Duplicate comments:
In `@process/test/exec.test.ts`:
- Around line 325-341: The test registers proc.around handlers after calling
exec("...") which spawns the child and can miss early stdout/stderr chunks; move
the around registration so handlers are installed before the child can emit
output (e.g., change the flow to register proc.around immediately after creating
the proc or use an exec option to pass stdout/stderr handlers), and also fix the
assertion by converting the concatenated Uint8Array[] into a string properly
instead of calling Uint8Array[].toString(); update references to exec,
proc.around, and proc.expect accordingly.
- Around line 306-323: The test is incorrectly calling .toString() on an array
of Uint8Array and conflating stdout/stderr into one array; update the
stdioApi.around handlers in the test (the generator callbacks passed to
stdioApi.around and the local variable currently named output) to collect stdout
and stderr separately (e.g., stdoutChunks and stderrChunks), decode each
Uint8Array chunk with a TextDecoder (or Buffer.from(...).toString()) before
pushing, then after proc.expect() join the decoded chunks and assert stdout and
stderr strings individually against the expected values; keep references to
stdioApi.around, the handler generator names (*stdout, *stderr), exec and
proc.expect to locate where to change.
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Fix all unresolved CodeRabbit comments on this PR:
- Push a commit to this branch (recommended)
- Create a new PR with the fixes
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cowboyd
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Mar 27, 2026
cowboyd
reviewed
Mar 28, 2026
| let next = yield* io.stdout.next(); | ||
| while (!next.done) { | ||
| yield* stdioApi.operations.stdout(next.value); | ||
| yield* Stdio.operations.stdout(next.value); |
Member
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Totally stylistic, but I like to destructure the operations from within the api.ts, that way you can:
import { stdout, stderr} from "../api.ts";it just makes the coupling cleaner.
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We already have the signal with those names which are also exported. Or are you thinking just to export them like that?
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Actionable comments posted: 2
♻️ Duplicate comments (2)
process/src/exec/win32.ts (1)
185-193:⚠️ Potential issue | 🟠 Major
aroundshould be bound toevalScopefor middleware to take effect on Win32.Unlike the POSIX implementation (which wraps
Stdio.aroundinevalScope.eval()), this returnsStdio.arounddirectly. Middleware registered viaproc.around()will modify the caller's context, not the context whereStdio.operations.stdout/stderrare invoked. This means Win32 process-level middleware won't intercept output.Proposed fix (align with POSIX implementation)
return { pid: pid as number, - around: Stdio.around, + *around(...args: Parameters<typeof Stdio.around>) { + const result = yield* evalScope.eval(() => Stdio.around(...args)); + return unbox(result); + }, stdin, stdout, stderr, join, expect, } satisfies Yielded<ReturnType<CreateOSProcess>>;🤖 Prompt for AI Agents
Verify each finding against the current code and only fix it if needed. In `@process/src/exec/win32.ts` around lines 185 - 193, The returned `around` is currently the raw Stdio.around, so middleware registered via proc.around() runs in the caller context instead of the process evalScope; update the return to bind `around` through the process `evalScope` like the POSIX side (i.e., replace direct `Stdio.around` with `evalScope.eval(Stdio.around)` or equivalent) so that `Stdio.operations.stdout/stderr` invoke middleware in the process context; modify the object returned by the function that yields CreateOSProcess (the value satisfying Yielded<ReturnType<CreateOSProcess>>) to use the eval-bound `around`.process/README.md (1)
73-82:⚠️ Potential issue | 🟡 MinorThe middleware example references the wrong
processobject.The example writes to
process.stdout.write(line)andprocess.stderr.write(line), butprocesshere refers to the localProcessvariable fromexec(), not Node's globalprocess. TheProcessinterface hasstdout/stderrasStream<string>, not writable streams.Suggested fix
await main(function* () { let process = yield* exec("npm install"); yield* process.around({ *stdout(line) { // it does this by default - process.stdout.write(line); + globalThis.process.stdout.write(line); }, *stderr(line) { // it does this by default - process.stderr.write(line); + globalThis.process.stderr.write(line); }, }); // Wait for the process to complete yield* process.expect(); });🤖 Prompt for AI Agents
Verify each finding against the current code and only fix it if needed. In `@process/README.md` around lines 73 - 82, The README example is shadowing Node's global process with the local Process from exec() and thus calls process.stdout.write/process.stderr.write on the wrong object; update the example inside process.around to reference Node's global process (e.g. globalThis.process.stdout.write(line) and globalThis.process.stderr.write(line)) or rename the local variable to avoid shadowing so the example clearly uses the real Node writable streams; mention the affected symbols: process.around, exec(), and the Process interface stdout/stderr to locate the code.
🤖 Prompt for all review comments with AI agents
Verify each finding against the current code and only fix it if needed.
Inline comments:
In `@process/src/api.ts`:
- Line 2: Replace the circular import by stopping the direct import of StdioApi
from "mod.ts" and instead import StdioApi from the module that actually
declares/exports that interface (the original API implementation file) so you no
longer depend on mod.ts which re-exports api.ts; update the import statement in
this file to a direct named import of StdioApi from its defining module (keeping
the same symbol name) to break the circular dependency.
In `@process/src/exec/types.ts`:
- Around line 46-53: The JSDoc example for proc.around's stdout handler
incorrectly calls yield* next(args) with an undefined variable args; update the
example inside the stdout middleware to pass the handler parameter (line) to
next instead (i.e., call next with the same line value), so the stdout example
uses the actual variable provided to the handler and avoids the undefined args
reference.
---
Duplicate comments:
In `@process/README.md`:
- Around line 73-82: The README example is shadowing Node's global process with
the local Process from exec() and thus calls
process.stdout.write/process.stderr.write on the wrong object; update the
example inside process.around to reference Node's global process (e.g.
globalThis.process.stdout.write(line) and globalThis.process.stderr.write(line))
or rename the local variable to avoid shadowing so the example clearly uses the
real Node writable streams; mention the affected symbols: process.around,
exec(), and the Process interface stdout/stderr to locate the code.
In `@process/src/exec/win32.ts`:
- Around line 185-193: The returned `around` is currently the raw Stdio.around,
so middleware registered via proc.around() runs in the caller context instead of
the process evalScope; update the return to bind `around` through the process
`evalScope` like the POSIX side (i.e., replace direct `Stdio.around` with
`evalScope.eval(Stdio.around)` or equivalent) so that
`Stdio.operations.stdout/stderr` invoke middleware in the process context;
modify the object returned by the function that yields CreateOSProcess (the
value satisfying Yielded<ReturnType<CreateOSProcess>>) to use the eval-bound
`around`.
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Fix all unresolved CodeRabbit comments on this PR:
- Push a commit to this branch (recommended)
- Create a new PR with the fixes
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process/README.mdprocess/mod.tsprocess/src/api.tsprocess/src/exec.tsprocess/src/exec/posix.tsprocess/src/exec/types.tsprocess/src/exec/win32.tsprocess/test/exec.test.ts
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⚠️ Outside diff range comments (1)
process/src/exec/win32.ts (1)
89-109:⚠️ Potential issue | 🟠 MajorResolve
stdoutDone/stderrDoneinfinally.There is now extra fallible work inside both reader loops before the resolver is completed. If either loop throws or is canceled, teardown can block forever waiting on the pending
*.Doneoperation. Moveclose()andresolve()intofinallyin both loops.🔧 Suggested fix
yield* spawn(function* () { - let next = yield* io.stdout.next(); - while (!next.done) { - yield* Stdio.operations.stdout(next.value); - stdout.send(next.value); - next = yield* io.stdout.next(); - } - stdout.close(); - io.stdoutDone.resolve(); + try { + let next = yield* io.stdout.next(); + while (!next.done) { + yield* Stdio.operations.stdout(next.value); + stdout.send(next.value); + next = yield* io.stdout.next(); + } + } finally { + stdout.close(); + io.stdoutDone.resolve(); + } }); yield* spawn(function* () { - let next = yield* io.stderr.next(); - while (!next.done) { - yield* Stdio.operations.stderr(next.value); - stderr.send(next.value); - next = yield* io.stderr.next(); - } - stderr.close(); - io.stderrDone.resolve(); + try { + let next = yield* io.stderr.next(); + while (!next.done) { + yield* Stdio.operations.stderr(next.value); + stderr.send(next.value); + next = yield* io.stderr.next(); + } + } finally { + stderr.close(); + io.stderrDone.resolve(); + } });Based on learnings, "Resources must clean up properly on scope exit in Effection code."
🤖 Prompt for AI Agents
Verify each finding against the current code and only fix it if needed. In `@process/src/exec/win32.ts` around lines 89 - 109, The reader loops inside the two spawn tasks (the generator passed to spawn that iterates io.stdout and io.stderr) currently call stdout.close()/stderr.close() and io.stdoutDone.resolve()/io.stderrDone.resolve() only after the while loop, which can hang teardown if an exception or cancellation occurs; move the close() and corresponding io.*Done.resolve() calls into a finally block inside each spawn generator so that stdout.close()/io.stdoutDone.resolve() and stderr.close()/io.stderrDone.resolve() are always executed on normal completion, error, or cancellation (keep the body that yields Stdio.operations.stdout/stderr and sends values unchanged).
🤖 Prompt for all review comments with AI agents
Verify each finding against the current code and only fix it if needed.
Inline comments:
In `@process/src/exec/win32.ts`:
- Around line 175-181: The code currently does an unconditional yield*
all([io.stdoutDone.operation, io.stderrDone.operation]) which can block forever
and prevent the killTree(pid) fallback from running; change this to race between
the stdio drain operations and the child process exiting so the cleanup path
remains reachable. Concretely, replace the all(...) wait with a race that
listens to io.stdoutDone.operation, io.stderrDone.operation, and a watcher for
childProcess.exitCode becoming non-null (or child exit event), then after the
race completes check if pid is set and childProcess.exitCode is still null and
call killTree(pid); keep use of existing symbols (all, race,
io.stdoutDone.operation, io.stderrDone.operation, childProcess.exitCode,
killTree, pid) so the forced cleanup runs even if stdio never drains.
- Around line 187-190: The public around(...) methods need explicit return
types: change the method signatures for around in both implementations (the one
that yields evalScope.eval(() => Stdio.around(...args)) and returns
unbox(result)) to declare ReturnType<typeof Stdio.around> (which is
Operation<void>) as the return type; update both the win32 around and the posix
around signatures to include this explicit return type while leaving the body
(evalScope.eval, Stdio.around call, unbox(result)) unchanged.
---
Outside diff comments:
In `@process/src/exec/win32.ts`:
- Around line 89-109: The reader loops inside the two spawn tasks (the generator
passed to spawn that iterates io.stdout and io.stderr) currently call
stdout.close()/stderr.close() and
io.stdoutDone.resolve()/io.stderrDone.resolve() only after the while loop, which
can hang teardown if an exception or cancellation occurs; move the close() and
corresponding io.*Done.resolve() calls into a finally block inside each spawn
generator so that stdout.close()/io.stdoutDone.resolve() and
stderr.close()/io.stderrDone.resolve() are always executed on normal completion,
error, or cancellation (keep the body that yields Stdio.operations.stdout/stderr
and sends values unchanged).
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Fix all unresolved CodeRabbit comments on this PR:
- Push a commit to this branch (recommended)
- Create a new PR with the fixes
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Actionable comments posted: 2
Caution
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⚠️ Outside diff range comments (1)
process/src/exec/posix.ts (1)
71-85:⚠️ Potential issue | 🔴 CriticalResolve the process only after the stdio middleware drains.
Lines 74 and 85 can now suspend inside
Stdio.operations.*(), butjoin()/expect()still resolve from the child"close"event alone. On POSIX,proc.around(() => proc.expect())can therefore unwind before the last chunk finishes its middleware path, so the tail of stdout/stderr can miss the middleware/finally handling.process/src/exec/win32.ts:123-128already waits forstdoutDone/stderrDonebefore resolvingprocessResult.🔧 Suggested change
yield* spawn(function* () { let value = yield* once<ProcessResultValue>(childProcess, "close"); + yield* all([io.stdoutDone.operation, io.stderrDone.operation]); processResult.resolve(Ok(value)); });🤖 Prompt for AI Agents
Verify each finding against the current code and only fix it if needed. In `@process/src/exec/posix.ts` around lines 71 - 85, The POSIX stdio spawn coroutines currently resolve io.stdoutDone/io.stderrDone before the Stdio.operations middleware has fully drained; update the spawned generators around Stdio.operations.stdout and Stdio.operations.stderr so they only call stdout.close() and io.stdoutDone.resolve() (and stderr.close()/io.stderrDone.resolve()) after the while-loop and after the yield* Stdio.operations.*(next.value) call completes for the last chunk, and ensure the parent process resolution (the code that uses join()/expect()) waits for those io.stdoutDone/io.stderrDone signals; in short, move or delay closing and resolving (stdout.close()/stderr.close() and io.stdoutDone.resolve()/io.stderrDone.resolve()) until after the Stdio.operations calls finish so proc.around(() => proc.expect()) cannot resolve before middleware drains.
🤖 Prompt for all review comments with AI agents
Verify each finding against the current code and only fix it if needed.
Inline comments:
In `@process/src/exec/posix.ts`:
- Around line 126-136: The finalizer inside ensure currently wraps both the
process.kill call and the pipe drain awaits in one try/catch, so if
process.kill(-childProcess.pid, "SIGTERM") throws the catch returns early and
io.stdoutDone/ io.stderrDone are never awaited; change the code in the
ensure(function* () { ... }) generator so that only the kill call is
try/catch-wrapped (or move the drain awaits into a finally block) and always
yield* all([io.stdoutDone.operation, io.stderrDone.operation]) regardless of
whether process.kill throws; reference childProcess.pid, process.kill, and
io.stdoutDone/io.stderrDone when making the update.
In `@process/src/exec/win32.ts`:
- Around line 157-185: The finalizer in ensure() calls ctrlc(pid) and writes
"Y\n" then immediately checks childProcess.exitCode and may call killTree(pid),
so the graceful shutdown never gets time to complete; after the stdin cleanup
(after stdin.end()) insert a wait for stdio to finish by yielding the io
stdout/stderr completion (e.g. yield* all([io.stdoutDone.operation,
io.stderrDone.operation])) or alternatively race that wait against a short
timeout, and only then check childProcess.exitCode and call killTree(pid) if
still running; update references around ensure, ctrlc, childProcess,
io.stdoutDone.operation, io.stderrDone.operation and killTree accordingly.
---
Outside diff comments:
In `@process/src/exec/posix.ts`:
- Around line 71-85: The POSIX stdio spawn coroutines currently resolve
io.stdoutDone/io.stderrDone before the Stdio.operations middleware has fully
drained; update the spawned generators around Stdio.operations.stdout and
Stdio.operations.stderr so they only call stdout.close() and
io.stdoutDone.resolve() (and stderr.close()/io.stderrDone.resolve()) after the
while-loop and after the yield* Stdio.operations.*(next.value) call completes
for the last chunk, and ensure the parent process resolution (the code that uses
join()/expect()) waits for those io.stdoutDone/io.stderrDone signals; in short,
move or delay closing and resolving (stdout.close()/stderr.close() and
io.stdoutDone.resolve()/io.stderrDone.resolve()) until after the
Stdio.operations calls finish so proc.around(() => proc.expect()) cannot resolve
before middleware drains.
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Fix all unresolved CodeRabbit comments on this PR:
- Push a commit to this branch (recommended)
- Create a new PR with the fixes
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♻️ Duplicate comments (1)
process/src/exec/win32.ts (1)
180-188:⚠️ Potential issue | 🟠 MajorStdio drain wait can still block the force-kill fallback.
If the child process ignores
ctrlc(pid)and keeps its stdout/stderr pipes open, line 182 will block indefinitely, preventing thekillTree(pid)fallback from ever executing. The previous review flagged this concern, and it appears unresolved.Consider racing the stdio drain against a bounded timeout or the process exit event:
🔧 Possible fix direction
- // depending on how we shutdown, this may already be closed and - // will pass immediately over the operations - yield* all([io.stdoutDone.operation, io.stderrDone.operation]); - - if (pid && childProcess.exitCode === null) { + // Race stdio drain against process exit; if neither completes quickly + // and process is still alive, escalate to force-kill + const exitOrDrain = yield* race([ + all([io.stdoutDone.operation, io.stderrDone.operation]), + processResult.operation, + ]); + + if (pid && childProcess.exitCode === null) {This ensures the force-kill path remains reachable even when stdio never drains. Alternatively, use
sleep()with a grace period ifraceagainstprocessResultis not sufficient.🤖 Prompt for AI Agents
Verify each finding against the current code and only fix it if needed. In `@process/src/exec/win32.ts` around lines 180 - 188, The current yield* all([io.stdoutDone.operation, io.stderrDone.operation]) can block forever and prevent the killTree(pid) fallback; change the logic in the shutdown sequence to race the stdio-drain operations against a bounded wait (either the child process exit/event or a timeout) so the path to killTree(pid) remains reachable: use a race between the combined stdio drain (io.stdoutDone.operation + io.stderrDone.operation) and a timeout or the child process exit detection (childProcess.exitCode !== null / process exit event), and only await the stdio drain if the race wins; otherwise proceed to call killTree(pid) (refer to io.stdoutDone.operation, io.stderrDone.operation, childProcess.exitCode, killTree, and any existing processResult/ctrlc logic when wiring the race).
🤖 Prompt for all review comments with AI agents
Verify each finding against the current code and only fix it if needed.
Duplicate comments:
In `@process/src/exec/win32.ts`:
- Around line 180-188: The current yield* all([io.stdoutDone.operation,
io.stderrDone.operation]) can block forever and prevent the killTree(pid)
fallback; change the logic in the shutdown sequence to race the stdio-drain
operations against a bounded wait (either the child process exit/event or a
timeout) so the path to killTree(pid) remains reachable: use a race between the
combined stdio drain (io.stdoutDone.operation + io.stderrDone.operation) and a
timeout or the child process exit detection (childProcess.exitCode !== null /
process exit event), and only await the stdio drain if the race wins; otherwise
proceed to call killTree(pid) (refer to io.stdoutDone.operation,
io.stderrDone.operation, childProcess.exitCode, killTree, and any existing
processResult/ctrlc logic when wiring the race).
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Motivation
With the adjustment in operation priorities, the classic
@effectionx/processlogging example no longer catches afinallyblock. It is subtle and you can work around it, but more ergonomic handling of use cases surrounding IO is through a middleware.Approach
We are setting the default to
process.std*.write()and one can add additional handling or remove/adjust that default through the@effectionx/context-apifunction that is exported from the package.Summary by CodeRabbit
New Features
Documentation
Tests
Chores