feat: cwd. (#34)

Author: knightedcodemonkey

README.md

@@ -135,6 +135,7 @@ type ModuleOptions = {
   idiomaticExports?: 'off' | 'safe' | 'aggressive'
   topLevelAwait?: 'error' | 'wrap' | 'preserve'
   out?: string
+  cwd?: string
   inPlace?: boolean
 }
 ```
@@ -159,7 +160,7 @@ type ModuleOptions = {
 - `cjsDefault` (`auto`): bundler-style default interop vs direct `module.exports`.
 - `idiomaticExports` (`safe`): when raising CJS to ESM, attempt to synthesize `export` statements directly when it is safe. `off` always uses the helper bag; `aggressive` currently matches `safe` heuristics.
 - `out`/`inPlace`: write the transformed code to a file; otherwise the function returns the transformed string only.
-- CommonJS → ESM lowering will throw on `with` statements and unshadowed `eval` calls to avoid unsound rewrites.
+- `cwd` (`process.cwd()`): Base directory used to resolve relative `out` paths.
 
 > [!NOTE]
 > Package-level metadata (`package.json` updates such as setting `"type": "module"` or authoring `exports`) is not edited by this tool today; plan that change outside the per-file transform.

package-lock.json

@@ -1,6 +1,6 @@
 {
   "name": "@knighted/module",
-  "version": "1.1.1",
+  "version": "1.2.0",
   "description": "Bidirectional transform for ES modules and CommonJS.",
   "type": "module",
   "main": "dist/module.js",
@@ -27,7 +27,7 @@
     "prettier": "prettier -w .",
     "prettier:check": "prettier -c .",
     "lint": "oxlint --config oxlint.json .",
-    "prepare": "husky install",
+    "prepare": "husky",
     "test": "c8 --reporter=text --reporter=text-summary --reporter=lcov tsx --test --test-reporter=spec test/*.ts",
     "build:types": "tsc --emitDeclarationOnly",
     "build:dual": "babel-dual-package src --extensions .ts",
@@ -72,7 +72,6 @@
   },
   "dependencies": {
     "magic-string": "^0.30.21",
-    "node-module-type": "^1.0.4",
     "oxc-parser": "^0.105.0",
     "periscopic": "^4.0.2"
   },

package.json

@@ -226,17 +226,19 @@ const defaultOptions = {
   idiomaticExports: 'safe',
   importMetaPrelude: 'auto',
   topLevelAwait: 'error',
+  cwd: undefined,
   out: undefined,
   inPlace: false,
 } satisfies ModuleOptions
 const transform = async (filename: string, options: ModuleOptions = defaultOptions) => {
   const opts = { ...defaultOptions, ...options, filePath: filename }
+  const cwdBase = opts.cwd ? resolve(opts.cwd) : process.cwd()
   const appendMode: AppendJsExtensionMode =
     options?.appendJsExtension ?? (opts.target === 'module' ? 'relative-only' : 'off')
   const dirIndex =
     opts.appendDirectoryIndex === undefined ? 'index.js' : opts.appendDirectoryIndex
   const detectCycles: DetectCircularRequires = opts.detectCircularRequires ?? 'off'
-  const file = resolve(filename)
+  const file = resolve(cwdBase, filename)
   const code = (await readFile(file)).toString()
   const ast = parse(filename, code)
   let source = await format(code, ast, opts)
@@ -261,7 +263,11 @@ const transform = async (filename: string, options: ModuleOptions = defaultOptio
     await detectCircularRequireGraph(file, detectCycles, dirIndex || 'index.js')
   }
 
-  const outputPath = opts.inPlace ? file : opts.out ? resolve(opts.out) : undefined
+  const outputPath = opts.inPlace
+    ? file
+    : opts.out
+      ? resolve(cwdBase, opts.out)
+      : undefined
 
   if (outputPath) {
     await writeFile(outputPath, source)

src/module.ts

@@ -65,6 +65,8 @@ export type ModuleOptions = {
   diagnostics?: (diag: Diagnostic) => void
   /** Optional source file path used for diagnostics context. */
   filePath?: string
+  /** Base directory used to resolve relative `out` paths; defaults to process.cwd(). */
+  cwd?: string
   /** Output directory or file path when writing. */
   out?: string
   /** Overwrite input files instead of writing to out. */

src/types.ts

@@ -0,0 +1,3 @@
+const value = { answer: 42 }
+
+module.exports = value

test/fixtures/cwdFile.cjs

@@ -4,7 +4,7 @@ import { spawnSync } from 'node:child_process'
 import { resolve, join } from 'node:path'
 import { pathToFileURL } from 'node:url'
 import { createRequire } from 'node:module'
-import { rm, stat, writeFile } from 'node:fs/promises'
+import { copyFile, mkdir, rm, stat, writeFile } from 'node:fs/promises'
 import type { Stats } from 'node:fs'
 
 import { transform } from '../src/module.js'
@@ -1819,6 +1819,64 @@ describe('@knighted/module', () => {
     assert.ok(result.includes('__dirname'))
   })
 
+  it('resolves relative out paths against cwd option', async t => {
+    const source = join(fixtures, 'file.cjs')
+    const relOut = join('cwd-out', 'out.mjs')
+    const expectedDir = join(fixtures, 'cwd-out')
+    const expected = join(expectedDir, 'out.mjs')
+    const unintendedDir = join(process.cwd(), 'cwd-out')
+    const valuesSrc = join(fixtures, 'values.cjs')
+    const valuesDst = join(expectedDir, 'values.cjs')
+
+    await mkdir(expectedDir, { recursive: true })
+    await copyFile(valuesSrc, valuesDst)
+
+    t.after(async () => {
+      await rm(expectedDir, { recursive: true, force: true })
+      if (unintendedDir !== expectedDir) {
+        await rm(unintendedDir, { recursive: true, force: true })
+      }
+    })
+
+    await transform(source, { target: 'module', out: relOut, cwd: fixtures })
+
+    assert.equal(await isValidFilename(expected), true)
+    if (unintendedDir !== expectedDir) {
+      assert.equal(await isValidFilename(join(unintendedDir, 'out.mjs')), false)
+    }
+
+    const { status } = spawnSync('node', [expected], { stdio: 'inherit' })
+    assert.equal(status, 0)
+  })
+
+  it('resolves relative input and output against cwd', async t => {
+    const relSource = 'cwdFile.cjs'
+    const relOut = join('cwd-rel', 'out.mjs')
+    const expectedDir = join(fixtures, 'cwd-rel')
+    const expectedOut = join(expectedDir, 'out.mjs')
+    const unintendedDir = join(process.cwd(), 'cwd-rel')
+
+    await mkdir(expectedDir, { recursive: true })
+
+    t.after(async () => {
+      await rm(expectedDir, { recursive: true, force: true })
+      if (unintendedDir !== expectedDir) {
+        await rm(unintendedDir, { recursive: true, force: true })
+      }
+    })
+
+    await transform(relSource, { target: 'module', cwd: fixtures, out: relOut })
+
+    assert.equal(await isValidFilename(expectedOut), true)
+    if (unintendedDir !== expectedDir) {
+      assert.equal(await isValidFilename(join(unintendedDir, 'out.mjs')), false)
+    }
+
+    const mod = await import(pathToFileURL(expectedOut).href)
+    const exported = (mod as any).default ?? (mod as any)
+    assert.equal(exported.answer, 42)
+  })
+
   it('writes transformed source to a file when option enabled', async t => {
     const mjs = join(fixtures, 'transformed.mjs')
     const cjs = join(fixtures, 'transformed.cjs')