test: Add snapshot test for barrel files (#90)

.eslintrc.json

@@ -1,5 +1,6 @@
 {
   "extends": "@tstv/eslint-config",
+  "ignorePatterns": ["src/test/fixtures/**"],
   "rules": {
     "@typescript-eslint/consistent-type-imports": "off"
   }

README.md

@@ -168,6 +168,11 @@ const __dirname = path.dirname(__filename);
 
 This program was born from an [inspiring conversation](https://twitter.com/bennycode/status/1693362836695585084) I had with [Basarat Ali Syed](https://twitter.com/basarat). I recommend checking out [Basarat's coding tutorials](https://www.youtube.com/@basarat). 👍
 
+## Testimonials
+
+- ts2esm got highlighted in Deno's article on [How to convert CommonJS to ESM](https://deno.com/blog/convert-cjs-to-esm#tools-for-migrating)
+- ts2esm helped migrating [cornerstonejs/cornerstone3D](https://github.com/cornerstonejs/cornerstone3D) from CommonJS to ESM
+
 ## Used By
 
 [<img src="https://ohif.org/static/c99ccbad57599dbf9f3490519c9b444f/63739/ohif-logo-dark.png" width="256"/>](https://ohif.org/)

package.json

@@ -28,7 +28,7 @@
     "prettier": "^3.3.3",
     "rimraf": "^6.0.1",
     "ts-node": "^10.9.2",
-    "vitest": "^2.0.5"
+    "vitest": "^2.1.3"
   },
   "engines": {
     "node": ">= 10.9"
@@ -74,7 +74,7 @@
     "release:minor": "npm version minor",
     "release:patch": "npm version patch",
     "start": "npm run test:types && node --no-warnings=ExperimentalWarning --loader ts-node/esm ./src/cli.ts",
-    "test": "npm run test:types && npm run test:unit:coverage",
+    "test": "npm run test:types && npm run test:unit",
     "test:types": "tsc --noEmit",
     "test:unit": "vitest run --passWithNoTests",
     "test:unit:coverage": "npm run test:unit -- --coverage.enabled"

src/converter/convertFile.test.ts

@@ -0,0 +1,31 @@
+import path from 'node:path';
+import {ProjectUtil} from '../util/ProjectUtil.js';
+import {convertFile} from './convertFile.js';
+
+describe('convertFile', () => {
+  const fixtures = path.join(process.cwd(), 'src', 'test', 'fixtures');
+
+  it('fixes imports from index files', async () => {
+    const projectDir = path.join(fixtures, 'index-import');
+    const projectConfig = path.join(projectDir, 'tsconfig.json');
+    const snapshot = path.join(projectDir, 'src', 'main.snap.ts');
+    const project = ProjectUtil.getProject(projectConfig);
+
+    const sourceFile = project.getSourceFile('main.ts')!;
+    const modifiedFile = convertFile(projectConfig, sourceFile, true);
+
+    await expect(modifiedFile.getText()).toMatchFileSnapshot(snapshot);
+  });
+
+  it('fixes imports when tsconfig has an "include" property', async () => {
+    const projectDir = path.join(fixtures, 'tsconfig-include');
+    const projectConfig = path.join(projectDir, 'tsconfig.json');
+    const snapshot = path.join(projectDir, 'src', 'consumer.snap.ts');
+    const project = ProjectUtil.getProject(projectConfig);
+
+    const sourceFile = project.getSourceFile('consumer.ts')!;
+    const modifiedFile = convertFile(projectConfig, sourceFile, true);
+
+    await expect(modifiedFile.getText()).toMatchFileSnapshot(snapshot);
+  });
+});

src/converter/convertFile.ts

@@ -0,0 +1,49 @@
+import {SourceFile, SyntaxKind} from 'ts-morph';
+import {rewrite} from '../main.js';
+import {ProjectUtil} from '../util/ProjectUtil.js';
+
+export function convertFile(tsConfigFilePath: string, sourceFile: SourceFile, dryRun: boolean) {
+  const filePath = sourceFile.getFilePath();
+  const project = ProjectUtil.getProject(tsConfigFilePath);
+  const paths = ProjectUtil.getPaths(project);
+  const projectDirectory = ProjectUtil.getRootDirectory(tsConfigFilePath);
+
+  let madeChanges: boolean = false;
+
+  sourceFile.getImportDeclarations().forEach(importDeclaration => {
+    importDeclaration.getDescendantsOfKind(SyntaxKind.StringLiteral).forEach(stringLiteral => {
+      const hasAttributesClause = !!importDeclaration.getAttributes();
+      const adjustedImport = rewrite({
+        hasAttributesClause,
+        paths,
+        projectDirectory,
+        sourceFilePath: sourceFile.getFilePath(),
+        stringLiteral,
+      });
+      madeChanges ||= adjustedImport;
+    });
+  });
+
+  sourceFile.getExportDeclarations().forEach(exportDeclaration => {
+    exportDeclaration.getDescendantsOfKind(SyntaxKind.StringLiteral).forEach(stringLiteral => {
+      const hasAttributesClause = !!exportDeclaration.getAttributes();
+      const adjustedExport = rewrite({
+        hasAttributesClause,
+        paths,
+        projectDirectory,
+        sourceFilePath: filePath,
+        stringLiteral,
+      });
+      madeChanges ||= adjustedExport;
+    });
+  });
+
+  if (madeChanges) {
+    if (!dryRun) {
+      sourceFile.saveSync();
+      console.log(`  Modified (🔧): ${filePath}`);
+    }
+  }
+
+  return sourceFile;
+}

src/main.ts

@@ -1,32 +1,26 @@
 import path from 'node:path';
-import {Project, StringLiteral, SyntaxKind} from 'ts-morph';
+import {StringLiteral} from 'ts-morph';
 import {applyModification} from './codemod/applyModification.js';
 import {convertTSConfig} from './codemod/convertTSConfig.js';
+import {convertFile} from './converter/convertFile.js';
 import {toImport, toImportAttribute} from './converter/ImportConverter.js';
 import {parseInfo, type ModuleInfo} from './parser/InfoParser.js';
 import {PathFinder} from './util/PathFinder.js';
-import {getNormalizedPath} from './util/PathUtil.js';
+import {getNormalizedPath, isNodeModuleRoot} from './util/PathUtil.js';
+import {ProjectUtil} from './util/ProjectUtil.js';
 
 /**
  * Traverses all source code files from a project and checks its import and export declarations.
  */
 export async function convert(tsConfigFilePath: string, debugLogging: boolean = false) {
-  const project = new Project({
-    // Limit the scope of source files to those directly listed as opposed to also all
-    // of the dependencies that may be imported. Never want to modify dependencies.
-    skipFileDependencyResolution: true,
-
-    tsConfigFilePath,
-  });
-  const projectDirectory = project.getRootDirectories()[0]?.getPath() || '';
-  // Note: getCompilerOptions() cannot be cached and has to be used everytime the config is accessed
-  const paths = project.getCompilerOptions().paths;
+  const project = ProjectUtil.getProject(tsConfigFilePath);
+  const paths = ProjectUtil.getPaths(project);
 
   // Check "module" and "moduleResolution" in "tsconfig.json"
   await convertTSConfig(tsConfigFilePath, project);
 
   // Add "type": "module" to "package.json"
-  const packageJsonPath = path.join(projectDirectory, 'package.json');
+  const packageJsonPath = path.join(ProjectUtil.getRootDirectory(tsConfigFilePath), 'package.json');
   await applyModification(packageJsonPath, '/type', 'module');
 
   if (paths && debugLogging) {
@@ -38,45 +32,11 @@ export async function convert(tsConfigFilePath: string, debugLogging: boolean =
     if (debugLogging) {
       console.log(` Checking (🧪): ${filePath}`);
     }
-
-    let madeChanges: boolean = false;
-
-    sourceFile.getImportDeclarations().forEach(importDeclaration => {
-      importDeclaration.getDescendantsOfKind(SyntaxKind.StringLiteral).forEach(stringLiteral => {
-        const hasAttributesClause = !!importDeclaration.getAttributes();
-        const adjustedImport = rewrite({
-          hasAttributesClause,
-          paths,
-          projectDirectory,
-          sourceFilePath: filePath,
-          stringLiteral,
-        });
-        madeChanges ||= adjustedImport;
-      });
-    });
-
-    sourceFile.getExportDeclarations().forEach(exportDeclaration => {
-      exportDeclaration.getDescendantsOfKind(SyntaxKind.StringLiteral).forEach(stringLiteral => {
-        const hasAttributesClause = !!exportDeclaration.getAttributes();
-        const adjustedExport = rewrite({
-          hasAttributesClause,
-          paths,
-          projectDirectory,
-          sourceFilePath: filePath,
-          stringLiteral,
-        });
-        madeChanges ||= adjustedExport;
-      });
-    });
-
-    if (madeChanges) {
-      sourceFile.saveSync();
-      console.log(`  Modified (🔧): ${filePath}`);
-    }
+    convertFile(tsConfigFilePath, sourceFile, false);
   });
 }
 
-function rewrite({
+export function rewrite({
   hasAttributesClause,
   paths,
   projectDirectory,
@@ -131,6 +91,11 @@ function createReplacementPath({
 
     const foundPath = PathFinder.findPath(baseFilePath, info.extension);
     if (foundPath) {
+      // TODO: Write test case for this condition, mock "path" and "fs" calls if necessary
+      if (foundPath.extension === '/index.js' && isNodeModuleRoot(baseFilePath)) {
+        // @fixes https://github.com/bennycode/ts2esm/issues/81#issuecomment-2437503011
+        return null;
+      }
       return toImport({...info, extension: foundPath.extension});
     }
   }

src/test/fixtures/index-import/main.snap.ts

@@ -0,0 +1,3 @@
+import {MY_CONSTANT} from './src/index';
+
+console.log(MY_CONSTANT);

src/test/fixtures/index-import/src/lib/index.ts

@@ -0,0 +1 @@
+export const MY_CONSTANT = 1337;

src/test/fixtures/index-import/src/main.snap.ts

@@ -0,0 +1,3 @@
+import {MY_CONSTANT} from './lib/index.js';
+
+console.log(MY_CONSTANT);

src/test/fixtures/index-import/src/main.ts

@@ -0,0 +1,4 @@
+// @ts-ignore
+import {MY_CONSTANT} from './lib';
+
+console.log(MY_CONSTANT);

src/test/fixtures/index-import/tsconfig.json

@@ -0,0 +1,10 @@
+{
+  "compilerOptions": {
+    "esModuleInterop": true,
+    "forceConsistentCasingInFileNames": true,
+    "module": "Node16",
+    "skipLibCheck": true,
+    "strict": true,
+    "target": "es2016"
+  }
+}

src/test/fixtures/tsconfig-include/consumer.snap.ts

@@ -0,0 +1,3 @@
+import {MY_CONSTANT} from './lib/producer.js';
+
+console.log(MY_CONSTANT);

src/test/fixtures/tsconfig-include/src/consumer.snap.ts

@@ -0,0 +1,3 @@
+import {MY_CONSTANT} from './lib/producer.js';
+
+console.log(MY_CONSTANT);

src/test/fixtures/tsconfig-include/src/consumer.ts

@@ -0,0 +1,4 @@
+// @ts-ignore
+import {MY_CONSTANT} from './lib/producer';
+
+console.log(MY_CONSTANT);

src/test/fixtures/tsconfig-include/src/lib/producer.ts

@@ -0,0 +1 @@
+export const MY_CONSTANT = 1337;

src/test/fixtures/tsconfig-include/tsconfig.json

@@ -0,0 +1,11 @@
+{
+  "compilerOptions": {
+    "esModuleInterop": true,
+    "forceConsistentCasingInFileNames": true,
+    "module": "Node16",
+    "skipLibCheck": true,
+    "strict": true,
+    "target": "es2016"
+  },
+  "include": ["src"]
+}

src/util/PathUtil.ts

@@ -1,4 +1,5 @@
 import path from 'node:path';
+import fs from 'node:fs';
 import type {ModuleInfo} from '../parser/InfoParser.js';
 
 /**
@@ -54,3 +55,10 @@ export function hasRelativePath(path: string) {
   }
   return path.startsWith('./') || path.startsWith('../');
 }
+
+export function isNodeModuleRoot(directory: string): boolean {
+  const isInNodeModules = directory.includes(`node_modules${path.sep}`);
+  const packageJsonPath = path.join(directory, 'package.json');
+  const packageJsonExists = fs.existsSync(packageJsonPath);
+  return isInNodeModules && packageJsonExists;
+}

src/util/ProjectUtil.ts

@@ -0,0 +1,20 @@
+import path from 'node:path';
+import {Project} from 'ts-morph';
+
+export const ProjectUtil = {
+  getPaths: (project: Project) => {
+    // Note: getCompilerOptions() cannot be cached and has to be used everytime the config is accessed
+    return project.getCompilerOptions().paths;
+  },
+  getProject: (tsConfigFilePath: string) => {
+    return new Project({
+      // Limit the scope of source files to those directly listed as opposed to also all
+      // of the dependencies that may be imported. Never want to modify dependencies.
+      skipFileDependencyResolution: true,
+      tsConfigFilePath,
+    });
+  },
+  getRootDirectory: (tsConfigFilePath: string): string => {
+    return path.dirname(tsConfigFilePath);
+  },
+};

tsconfig.json

@@ -1,9 +1,10 @@
 {
   "$schema": "https://json.schemastore.org/tsconfig",
-  "extends": "@tstv/tsconfig-common/tsconfig.json",
   "compilerOptions": {
     "outDir": "dist",
     "types": ["vitest/globals"]
   },
+  "exclude": ["src/test/fixtures/**"],
+  "extends": "@tstv/tsconfig-common/tsconfig.json",
   "include": ["src/**/*", "vitest.config.ts"]
 }