fix: properly load index.js ES modules (cont) (#417)

* fix: properly load index.js ES modules * use path.join * cover all scenarios * fix indentation * Address linting issues * Add additional checks * Add tests Co-authored-by: Rodrigo Pastro <[email protected]> Co-authored-by: peternhale <[email protected]> Co-authored-by: Mike Donnalley <[email protected]>
oclif · May 18, 2022 · 77ba8b8 · 77ba8b8
1 parent 44eb6d8
commit 77ba8b8
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Showing 4 changed files with 64 additions and 9 deletions.
diff --git a/src/module-loader.ts b/src/module-loader.ts
@@ -139,16 +139,28 @@ export default class ModuleLoader {
  } catch {
  filePath = Config.tsPath(config.root, modulePath)
 
- // Try all supported extensions.
- if (!fs.existsSync(filePath)) {
- // eslint-disable-next-line camelcase
- for (const extension of s_EXTENSIONS) {
- const testPath = `${filePath}${extension}`
-
- if (fs.existsSync(testPath)) {
- filePath = testPath
- break
+ let fileExists = false
+ let isDirectory = false
+ if (fs.existsSync(filePath)) {
+ fileExists = true
+ try {
+ if (fs.lstatSync(filePath)?.isDirectory?.()) {
+ fileExists = false
+ isDirectory = true
  }
+ } catch {}
+ }
+
+ if (!fileExists) {
+ // Try all supported extensions.
+ let foundPath = ModuleLoader.findFile(filePath)
+ if (!foundPath && isDirectory) {
+ // Since filePath is a directory, try looking for index.js file.
+ foundPath = ModuleLoader.findFile(path.join(filePath, 'index'))
+ }
+
+ if (foundPath) {
+ filePath = foundPath
  }
  }
 
@@ -157,4 +169,24 @@ export default class ModuleLoader {
 
  return {isESM, filePath}
  }
+
+ /**
+ * Try adding the different extensions from `s_EXTENSIONS` to find the file.
+ *
+ * @param {string} filePath - File path to load.
+ *
+ * @returns {string | null} Modified file path including extension or null if file is not found.
+ */
+ static findFile(filePath: string) : string | null {
+ // eslint-disable-next-line camelcase
+ for (const extension of s_EXTENSIONS) {
+ const testPath = `${filePath}${extension}`
+
+ if (fs.existsSync(testPath)) {
+ return testPath
+ }
+ }
+
+ return null
+ }
 }
diff --git a/test/module-loader/fixtures/esm/index/js/index.js b/test/module-loader/fixtures/esm/index/js/index.js
@@ -0,0 +1,3 @@
+export default 'SUCCESS'
+
+export const namedExport = 'SUCCESS_NAMED'
diff --git a/test/module-loader/fixtures/esm/index/mjs/index.mjs b/test/module-loader/fixtures/esm/index/mjs/index.mjs
@@ -0,0 +1,3 @@
+export default 'SUCCESS'
+
+export const namedExport = 'SUCCESS_NAMED'
diff --git a/test/module-loader/module-loader.test.ts b/test/module-loader/module-loader.test.ts
@@ -118,6 +118,23 @@ const data = {
  isESM: false,
  },
 
+ // Directory / ESM source file with .js extension. Loads package.json in './test/module-loader/fixtures/esm/' for getPackageType check.
+ {
+ path: './test/module-loader/fixtures/esm/index/js',
+ defaultModule: '{"default":"SUCCESS","namedExport":"SUCCESS_NAMED"}',
+ filePath: `${path.resolve('./test/module-loader/fixtures/esm/index/js/index.js')}`,
+ isESM: true,
+ isESMOverride: false, // With no extension `ModuleLoader.isPathModule` will return CJS
+ },
+ // Directory / ESM source file with .mjs extension. Loads package.json in './test/module-loader/fixtures/esm/' for getPackageType check.
+ {
+ path: './test/module-loader/fixtures/esm/index/mjs',
+ defaultModule: '{"default":"SUCCESS","namedExport":"SUCCESS_NAMED"}',
+ filePath: `${path.resolve('./test/module-loader/fixtures/esm/index/mjs/index.mjs')}`,
+ isESM: true,
+ isESMOverride: false, // With no extension `ModuleLoader.isPathModule` will return CJS
+ },
+
  // CJS NPM module; just check that it loads as CJS.
  {
  path: 'eslint',