feat: Convert dynamic imports

src/converter/convertFile.test.ts

@@ -3,124 +3,68 @@ import {ProjectUtil} from '../util/ProjectUtil.js';
 import {convertFile} from './convertFile.js';
 
 describe('convertFile', () => {
-  const fixtures = path.join(process.cwd(), 'src', 'test', 'fixtures');
+  function testFileConversion(directoryName: string, fileName = 'main', extension = 'ts') {
+    const fixtures = path.join(process.cwd(), 'src', 'test', 'fixtures');
+    const projectDir = path.join(fixtures, directoryName);
+    const projectConfig = path.join(projectDir, 'tsconfig.json');
+    const project = ProjectUtil.getProject(projectConfig);
+
+    const snapshot = path.join(projectDir, 'src', `${fileName}.snap.${extension}`);
+    const sourceFileName = `${fileName}.${extension}`;
+    const sourceFile = project.getSourceFile(sourceFileName);
+    if (!sourceFile) {
+      throw new Error(`File "${sourceFileName}" not found.`);
+    }
+    const modifiedFile = convertFile(sourceFile);
+    if (!modifiedFile) {
+      throw new Error(`File "${sourceFileName}" was not converted.`);
+    }
+    return expect(modifiedFile.getFullText()).toMatchFileSnapshot(snapshot);
+  }
 
   describe('imports', () => {
-    it('fixes imports from index files', async () => {
-      const projectDir = path.join(fixtures, 'index-import');
-      const projectConfig = path.join(projectDir, 'tsconfig.json');
-      const project = ProjectUtil.getProject(projectConfig);
-
-      const snapshot = path.join(projectDir, 'src', 'main.snap.ts');
-      const sourceFile = project.getSourceFile('main.ts')!;
-      const modifiedFile = convertFile(sourceFile);
-
-      await expect(modifiedFile?.getFullText()).toMatchFileSnapshot(snapshot);
+    it('converts imports from index files', async () => {
+      await testFileConversion('index-import');
     });
 
-    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 project = ProjectUtil.getProject(projectConfig);
-
-      const snapshot = path.join(projectDir, 'src', 'consumer.snap.ts');
-      const sourceFile = project.getSourceFile('consumer.ts')!;
-      const modifiedFile = convertFile(sourceFile);
-
-      await expect(modifiedFile?.getFullText()).toMatchFileSnapshot(snapshot);
+    it('converts imports when tsconfig has an "include" property', async () => {
+      await testFileConversion('tsconfig-include', 'consumer');
     });
 
-    it('turns CJS require statements into ESM imports', async () => {
-      const projectDir = path.join(fixtures, 'require-import');
-      const projectConfig = path.join(projectDir, 'tsconfig.json');
-      const project = ProjectUtil.getProject(projectConfig);
-
-      const snapshot = path.join(projectDir, 'src', 'main.snap.ts');
-      const sourceFile = project.getSourceFile('main.ts')!;
-      const modifiedFile = convertFile(sourceFile);
+    it('converts CJS require statements into ESM imports', async () => {
+      await testFileConversion('require-import');
+    });
 
-      await expect(modifiedFile?.getFullText()).toMatchFileSnapshot(snapshot);
+    it('converts dynamic imports', async () => {
+      await testFileConversion('dynamic-imports');
     });
 
     it('handles index files referenced with a trailing slash', async () => {
-      const projectDir = path.join(fixtures, 'trailing-slash');
-      const projectConfig = path.join(projectDir, 'tsconfig.json');
-      const project = ProjectUtil.getProject(projectConfig);
-
-      const snapshot = path.join(projectDir, 'src', 'main.snap.ts');
-      const sourceFile = project.getSourceFile('main.ts')!;
-      const modifiedFile = convertFile(sourceFile);
-
-      await expect(modifiedFile?.getFullText()).toMatchFileSnapshot(snapshot);
+      await testFileConversion('trailing-slash');
     });
 
     it('handles files with a Shebang (#!) at the beginning', async () => {
-      const projectDir = path.join(fixtures, 'cjs-shebang');
-      const projectConfig = path.join(projectDir, 'tsconfig.json');
-      const project = ProjectUtil.getProject(projectConfig);
-
-      const snapshot = path.join(projectDir, 'src', 'main.snap.ts');
-      const sourceFile = project.getSourceFile('main.ts')!;
-      const modifiedFile = convertFile(sourceFile);
-
-      await expect(modifiedFile?.getFullText()).toMatchFileSnapshot(snapshot);
+      await testFileConversion('cjs-shebang');
     });
 
     it('handles named imports from require statements', async () => {
-      const projectDir = path.join(fixtures, 'cjs-destructuring');
-      const projectConfig = path.join(projectDir, 'tsconfig.json');
-      const project = ProjectUtil.getProject(projectConfig);
-
-      const snapshot = path.join(projectDir, 'src', 'main.snap.ts');
-      const sourceFile = project.getSourceFile('main.ts')!;
-      const modifiedFile = convertFile(sourceFile);
-
-      await expect(modifiedFile?.getFullText()).toMatchFileSnapshot(snapshot);
+      await testFileConversion('cjs-destructuring');
     });
   });
 
   describe('exports', () => {
     describe('CJS (module.exports) to ESM', () => {
       it('converts default and named exports', async () => {
-        const projectDir = path.join(fixtures, 'module-exports');
-        const projectConfig = path.join(projectDir, 'tsconfig.json');
-        const project = ProjectUtil.getProject(projectConfig);
-
-        const snapshot = path.join(projectDir, 'src', 'main.snap.ts');
-        const sourceFile = project.getSourceFile('main.ts')!;
-        const modifiedFile = convertFile(sourceFile);
-
-        await expect(modifiedFile?.getFullText()).toMatchFileSnapshot(snapshot);
+        await testFileConversion('module-exports');
       });
 
       it('converts multiple named exports', async () => {
-        const projectDir = path.join(fixtures, 'module-exports');
-        const projectConfig = path.join(projectDir, 'tsconfig.json');
-        const project = ProjectUtil.getProject(projectConfig);
-
-        const snapshot = path.join(projectDir, 'src', 'multiple-named-exports.snap.ts');
-        const sourceFile = project.getSourceFile('multiple-named-exports.ts')!;
-        const modifiedFile = convertFile(sourceFile);
-
-        await expect(modifiedFile?.getFullText()).toMatchFileSnapshot(snapshot);
+        await testFileConversion('module-exports', 'multiple-named-exports');
       });
 
       it('handles functions exported as default from plain JavaScript files', async () => {
-        const projectDir = path.join(fixtures, 'module-exports-function-js');
-        const projectConfig = path.join(projectDir, 'tsconfig.json');
-        const project = ProjectUtil.getProject(projectConfig);
-
-        const snapshot = path.join(projectDir, 'src', 'build-example-index.snap.js');
-        const snapshot2 = path.join(projectDir, 'src', 'build-example-index-markdown.snap.js');
-
-        const sourceFile = project.getSourceFile('build-example-index.js')!;
-        const modifiedFile = convertFile(sourceFile);
-
-        const sourceFile2 = project.getSourceFile('build-example-index-markdown.js')!;
-        const modifiedFile2 = convertFile(sourceFile2);
-
-        await expect(modifiedFile?.getFullText()).toMatchFileSnapshot(snapshot);
-        await expect(modifiedFile2?.getFullText()).toMatchFileSnapshot(snapshot2);
+        await testFileConversion('module-exports-function-js', 'build-example-index', 'js');
+        await testFileConversion('module-exports-function-js', 'build-example-index-markdown', 'js');
       });
     });
   });

src/converter/convertFile.ts

@@ -1,7 +1,8 @@
 import {SourceFile} from 'ts-morph';
-import {replaceFileExtensions} from './replacer/replaceFileExtensions.js';
+import {addFileExtensions} from './replacer/addFileExtensions.js';
 import {replaceModuleExports} from './replacer/replaceModuleExports.js';
-import {replaceRequires} from './replacer/replaceRequire.js';
+import {replaceRequiresAndShebang} from './replacer/replaceRequiresAndShebang.js';
+import {replaceDynamicImports} from './replacer/replaceDynamicImports.js';
 
 /**
  * Returns the source file ONLY if it was modified.
@@ -10,25 +11,31 @@ export function convertFile(sourceFile: SourceFile) {
   let madeChanges: boolean = false;
 
   // Update "require" statements to "import" statements
-  const updatedRequires = replaceRequires(sourceFile);
+  const updatedRequires = replaceRequiresAndShebang(sourceFile);
   if (updatedRequires) {
     madeChanges = true;
   }
 
+  // Update "await import" statements
+  const updatedDynamicImports = replaceDynamicImports(sourceFile);
+  if (updatedDynamicImports) {
+    madeChanges = true;
+  }
+
   // Update "module.exports" statements to "export" statements
   const replacedModuleExports = replaceModuleExports(sourceFile);
   if (replacedModuleExports) {
     madeChanges = true;
   }
 
   // Add explicit file extensions to imports
-  const replacedImportFileExtensions = replaceFileExtensions(sourceFile, 'import');
+  const replacedImportFileExtensions = addFileExtensions(sourceFile, 'import');
   if (replacedImportFileExtensions) {
     madeChanges = true;
   }
 
   // Add explicit file extensions to exports
-  const replacedExportFileExtensions = replaceFileExtensions(sourceFile, 'export');
+  const replacedExportFileExtensions = addFileExtensions(sourceFile, 'export');
   if (replacedExportFileExtensions) {
     madeChanges = true;
   }

src/converter/replacer/addFileExtensions.ts

@@ -0,0 +1,27 @@
+import {SourceFile, SyntaxKind} from 'ts-morph';
+import {replaceModulePath} from '../../util/replaceModulePath.js';
+
+export function addFileExtensions(sourceFile: SourceFile, type: 'import' | 'export') {
+  let madeChanges: boolean = false;
+  const identifier = type === 'import' ? 'getImportDeclarations' : 'getExportDeclarations';
+
+  sourceFile[identifier]().forEach(declaration => {
+    try {
+      declaration.getDescendantsOfKind(SyntaxKind.StringLiteral).forEach(stringLiteral => {
+        const hasAttributesClause = !!declaration.getAttributes();
+        const adjustedImport = replaceModulePath({
+          hasAttributesClause,
+          sourceFile,
+          stringLiteral,
+        });
+        if (adjustedImport) {
+          madeChanges = true;
+        }
+      });
+    } catch (error: unknown) {
+      console.error(` There was an issue with "${sourceFile.getFilePath()}":`, error);
+    }
+  });
+
+  return madeChanges;
+}

src/converter/replacer/replaceDynamicImports.ts

@@ -0,0 +1,29 @@
+import {SourceFile, SyntaxKind} from 'ts-morph';
+import {replaceModulePath} from '../../util/replaceModulePath.js';
+
+export function replaceDynamicImports(sourceFile: SourceFile) {
+  let madeChanges: boolean = false;
+
+  sourceFile.getVariableStatements().forEach(statement => {
+    statement.getDeclarations().forEach(declaration => {
+      const initializer = declaration.getInitializerIfKind(SyntaxKind.AwaitExpression);
+      const callExpression = initializer?.getExpressionIfKind(SyntaxKind.CallExpression);
+      const importExpression = callExpression?.getExpressionIfKind(SyntaxKind.ImportKeyword);
+      if (importExpression) {
+        const literals = initializer?.getDescendantsOfKind(SyntaxKind.StringLiteral);
+        literals?.forEach(stringLiteral => {
+          const adjustedImport = replaceModulePath({
+            hasAttributesClause: false,
+            sourceFile,
+            stringLiteral,
+          });
+          if (adjustedImport) {
+            madeChanges = true;
+          }
+        });
+      }
+    });
+  });
+
+  return madeChanges;
+}

src/converter/replacer/replaceRequire.ts → src/converter/replacer/replaceRequiresAndShebang.ts

@@ -17,19 +17,19 @@ function replaceRequire(sourceFile: SourceFile, statement: VariableStatement) {
 
   // Get call expression from variable declaration
   // @see https://github.com/dsherret/ts-morph/issues/682#issuecomment-520246214
-  const initializer = declaration.getInitializerIfKind(SyntaxKind.CallExpression);
-  if (!initializer) {
+  const callExpression = declaration.getInitializerIfKind(SyntaxKind.CallExpression);
+  if (!callExpression) {
     return false;
   }
 
   // Verify that we have a "require" call
-  const identifier = initializer.getExpression().asKind(SyntaxKind.Identifier);
+  const identifier = callExpression.getExpressionIfKind(SyntaxKind.Identifier);
   if (identifier?.getText() !== 'require') {
     return false;
   }
 
   // Extract the argument passed to "require" and use its value
-  const requireArguments = initializer.getArguments();
+  const requireArguments = callExpression.getArguments();
   const packageName = requireArguments[0];
   if (!packageName) {
     return false;
@@ -52,15 +52,15 @@ function replaceRequire(sourceFile: SourceFile, statement: VariableStatement) {
   return true;
 }
 
-export function replaceRequires(sourceFile: SourceFile) {
+export function replaceRequiresAndShebang(sourceFile: SourceFile) {
   let madeChanges: boolean = false;
 
   // Handle files with "#! /usr/bin/env node" pragma
   const firstStatement = sourceFile.getStatements()[0];
   const hasShebang = firstStatement && firstStatement?.getFullText().startsWith('#!');
   let shebangText = '';
   if (hasShebang) {
-    // The full text contains both comments and the following statment,
+    // The full text contains both comments and the following statement,
     // so we are separating the statement into comments and the instruction that follow on the next line.
     const {statement: lineAfterShebang, comment} = NodeUtil.extractComment(firstStatement);
     shebangText = comment;
@@ -73,11 +73,15 @@ export function replaceRequires(sourceFile: SourceFile) {
   sourceFile.getVariableStatements().forEach(statement => {
     try {
       const updatedRequire = replaceRequire(sourceFile, statement);
+
       if (updatedRequire) {
         madeChanges = true;
       }
+
+      return madeChanges;
     } catch (error: unknown) {
       console.error(` There was an issue with "${sourceFile.getFilePath()}":`, error);
+      return false;
     }
   });
 

src/test/fixtures/dynamic-imports/src/main.snap.ts

@@ -0,0 +1,2 @@
+// @ts-ignore
+const module = await import('./my-function.function.js');

src/test/fixtures/dynamic-imports/src/main.ts

@@ -0,0 +1,2 @@
+// @ts-ignore
+const module = await import('./my-function.function');

src/test/fixtures/dynamic-imports/src/my-function.function.ts

@@ -0,0 +1,3 @@
+export function hereIAm() {
+  console.log('test');
+}

src/test/fixtures/dynamic-imports/tsconfig.json

@@ -0,0 +1,10 @@
+{
+  "compilerOptions": {
+    "esModuleInterop": true,
+    "forceConsistentCasingInFileNames": true,
+    "module": "node16",
+    "skipLibCheck": true,
+    "strict": true,
+    "target": "ES2020"
+  }
+}