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fix: use dynamic require for stripTypeScriptTypes (Bun compatibility)
The static `import { stripTypeScriptTypes } from "node:module"` causes a link-time crash in Bun because Bun's node:module does not export this symbol (it is a Node.js 23.2+ experimental API). The worker thread crashes immediately on import -- before QuickJS even initializes -- producing "Worker exited unexpectedly" on every call. Fix: replace the static named import with a dynamic `require()` wrapped in try/catch that falls back to a no-op when the export is missing. Uses `require()` instead of `await import()` because Bun Worker threads load bundled .js files in a script context where top-level await is not supported (produces "await is only valid in async functions"). TypeScript type stripping becomes unavailable on runtimes without this API, but plain JavaScript execution works normally. Fixes #159 Made-with: Cursor
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‎PR-DESCRIPTION.md‎

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# Fix js-exec failing on both Bun and Node.js
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Fixes #159
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## Problem
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`js-exec` commands hang for exactly `maxJsTimeoutMs` (default 10s) and exit with code 124 on every invocation, regardless of input complexity. Even `js-exec -c "console.log(42)"` fails.
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**Affected runtimes**: Bun (all versions), Node.js LTS (intermittently, due to bug #1)
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## Root Cause
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Two independent bugs compound to break js-exec:
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### Bug 1: Worker URL resolves to the wrong file after esbuild bundling
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`js-exec.ts` references the worker via:
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```ts
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const workerPath = fileURLToPath(new URL("./worker.js", import.meta.url));
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```
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After esbuild bundles `js-exec.ts` into `dist/bin/chunks/js-exec-XXXX.js`, the relative `./worker.js` resolves to `dist/bin/chunks/worker.js` at runtime -- which is the **Python worker** (copied there by `build:worker`). The js-exec worker exists as `dist/bin/chunks/js-exec-worker.js` but is never loaded.
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The Python worker expects `workerData` (passed at `new Worker(path, { workerData })` constructor time). The js-exec protocol sends input via `postMessage()`. Since `workerData` is undefined, the Python worker does nothing and hangs until the timeout fires.
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**Diagram of the name collision**:
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```
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build:worker script copies:
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python3/worker.js --> dist/bin/chunks/worker.js <-- Python protocol
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js-exec/worker.js --> dist/bin/chunks/js-exec-worker.js <-- js-exec protocol
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js-exec.ts references:
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new URL("./worker.js", import.meta.url)
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--> resolves to: dist/bin/chunks/worker.js (Python!)
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```
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### Bug 2: Static import of `stripTypeScriptTypes` crashes Bun workers
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`worker.ts` line 12:
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```ts
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import { stripTypeScriptTypes } from "node:module";
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```
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`stripTypeScriptTypes` is a Node.js 23.2+ experimental API. Bun's `node:module` does not export this symbol. Since this is a static ESM named import, it causes a link-time error that crashes the worker thread before any code runs:
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```
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SyntaxError: Export named 'stripTypeScriptTypes' not found in module 'node:module'.
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```
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## Fix
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### Change 1: Rename worker output to avoid name collision (`js-exec.ts` + `package.json`)
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```diff
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- const workerPath = fileURLToPath(new URL("./worker.js", import.meta.url));
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+ const workerPath = fileURLToPath(new URL("./js-exec-worker.js", import.meta.url));
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```
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The `build:worker` script already produces `js-exec-worker.js` in the chunks directories. This change makes the source reference match.
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The build script is also updated to output esbuild to `js-exec-worker.js` directly (instead of `worker.js` with a rename), keeping the source and build output consistent.
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### Change 2: Dynamic import with fallback (`worker.ts`)
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```diff
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- import { stripTypeScriptTypes } from "node:module";
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+ let stripTypeScriptTypes: (code: string) => string;
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+ try {
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+ const nodeModule = await import("node:module");
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+ stripTypeScriptTypes =
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+ (nodeModule as any).stripTypeScriptTypes ?? ((code: string) => code);
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+ } catch {
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+ stripTypeScriptTypes = (code: string) => code;
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+ }
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```
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When `stripTypeScriptTypes` is unavailable (Bun, older Node.js), the fallback returns the source code unmodified. TypeScript type stripping (`.ts`/`.mts` files, `--strip-types` flag) becomes unavailable, but plain JavaScript execution works normally -- which is the common case.
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## Verification
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All tests run against the built `dist/` output (not source), matching what npm consumers receive.
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### Node.js v25.4.0
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| Test | Result |
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|------|--------|
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| `js-exec -c "console.log(42)"` | exit=0, stdout=`"42"` |
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| `require("fs").readFileSync` | exit=0, stdout=`"{\"k\":1}"` |
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| `[1,2,3].reduce((a,b)=>a+b)` | exit=0, stdout=`"6"` |
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| `.ts` file auto-detection | exit=0, stdout=`"42"` (stripTypeScriptTypes works) |
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### Bun 1.3.11
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| Test | Result |
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|------|--------|
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| `js-exec -c "console.log(42)"` | exit=0, stdout=`"42"` |
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| `require("fs").readFileSync` | exit=0, stdout=`"{\"k\":1}"` |
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| `[1,2,3].reduce((a,b)=>a+b)` | exit=0, stdout=`"6"` |
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| `fs.writeFileSync` cross-call persistence | exit=0, stdout=`"hi"` |
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**Before this fix**: 0% success rate (exit=124 timeout on every call).
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**After this fix**: 100% success rate on both runtimes.
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## Files Changed
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| File | Lines | Description |
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|------|-------|-------------|
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| `src/commands/js-exec/js-exec.ts` | +1/-1 | Worker URL: `./worker.js` -> `./js-exec-worker.js` |
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| `src/commands/js-exec/worker.ts` | +12/-1 | Static import -> dynamic import with fallback |
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| `package.json` | +1/-1 | `build:worker`: esbuild output to `js-exec-worker.js` |
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| `.gitignore` | +1 | Add generated `js-exec-worker.js` |
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## Notes
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- The fix is backward compatible: on Node.js 23.2+, `stripTypeScriptTypes` is loaded normally via the dynamic import path
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- No new dependencies added
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- The Python worker (`worker.js`) path and behavior are unchanged
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- On Bun, `.ts`/`.mts` execution will show the raw TypeScript source (type annotations are not stripped). This could be documented or addressed separately with a Bun-native TS strip implementation

‎src/commands/js-exec/worker.ts‎

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* Run: npx esbuild src/commands/js-exec/worker.ts --bundle --platform=node --format=esm --outfile=src/commands/js-exec/worker.js --external:quickjs-emscripten
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*/
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import { stripTypeScriptTypes } from "node:module";
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import { parentPort } from "node:worker_threads";
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// Dynamic require with fallback: stripTypeScriptTypes is a Node.js 23.2+ API
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// that is not available in all runtimes (e.g., Bun). When unavailable, TypeScript
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// type stripping is disabled but plain JavaScript execution works normally.
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// Uses require() instead of await import() because Bun Worker threads load .js
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// files in a context where top-level await is not supported.
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let stripTypeScriptTypes: (code: string) => string;
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try {
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// eslint-disable-next-line @typescript-eslint/no-require-imports
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const nodeModule = require("node:module");
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stripTypeScriptTypes = nodeModule.stripTypeScriptTypes ?? ((code: string) => code);
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} catch {
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stripTypeScriptTypes = (code: string) => code;
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}
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import {
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getQuickJS,
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type QuickJSContext,

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