babel · nicolo-ribaudo · May 24, 2023 · Mar 15, 2023 · Mar 15, 2023 · Mar 30, 2023
diff --git a/packages/babel-parser/src/plugins/typescript/index.ts b/packages/babel-parser/src/plugins/typescript/index.ts
@@ -2017,6 +2017,7 @@ export default (superClass: ClassWithMixin<typeof Parser, IJSXParserMixin>) =>
       // For compatibility to estree we cannot call parseLiteral directly here
       node.expression = super.parseExprAtom() as N.StringLiteral;
       this.expect(tt.parenR);
+      this.sawUnambiguousESM = true;
       return this.finishNode(node, "TSExternalModuleReference");
     }
 
@@ -2788,6 +2789,7 @@ export default (superClass: ClassWithMixin<typeof Parser, IJSXParserMixin>) =>
         const assign = node as Undone<N.TsExportAssignment>;
         assign.expression = super.parseExpression();
         this.semicolon();
+        this.sawUnambiguousESM = true;
         return this.finishNode(assign, "TSExportAssignment");
       } else if (this.eatContextual(tt._as)) {
         // `export as namespace A;`

diff --git a/packages/babel-parser/test/fixtures/typescript/export/equals-in-script/input.ts b/packages/babel-parser/test/fixtures/typescript/export/equals-in-script/input.ts
@@ -0,0 +1 @@
+export = f;
diff --git a/packages/babel-parser/test/fixtures/typescript/export/equals-in-script/options.json b/packages/babel-parser/test/fixtures/typescript/export/equals-in-script/options.json
@@ -0,0 +1,3 @@
+{
+  "sourceType": "script"
+}
diff --git a/packages/babel-parser/test/fixtures/typescript/export/equals-in-script/output.json b/packages/babel-parser/test/fixtures/typescript/export/equals-in-script/output.json
@@ -0,0 +1,25 @@
+{
+  "type": "File",
+  "start":0,"end":11,"loc":{"start":{"line":1,"column":0,"index":0},"end":{"line":1,"column":11,"index":11}},
+  "errors": [
+    "SyntaxError: 'import' and 'export' may appear only with 'sourceType: \"module\"' (1:0)"
+  ],
+  "program": {
+    "type": "Program",
+    "start":0,"end":11,"loc":{"start":{"line":1,"column":0,"index":0},"end":{"line":1,"column":11,"index":11}},
+    "sourceType": "script",
+    "interpreter": null,
+    "body": [
+      {
+        "type": "TSExportAssignment",
+        "start":0,"end":11,"loc":{"start":{"line":1,"column":0,"index":0},"end":{"line":1,"column":11,"index":11}},
+        "expression": {
+          "type": "Identifier",
+          "start":9,"end":10,"loc":{"start":{"line":1,"column":9,"index":9},"end":{"line":1,"column":10,"index":10},"identifierName":"f"},
+          "name": "f"
+        }
+      }
+    ],
+    "directives": []
+  }
+}
diff --git a/packages/babel-parser/test/fixtures/typescript/export/equals-in-unambiguous/input.ts b/packages/babel-parser/test/fixtures/typescript/export/equals-in-unambiguous/input.ts
@@ -0,0 +1 @@
+export = f;
diff --git a/packages/babel-parser/test/fixtures/typescript/export/equals-in-unambiguous/options.json b/packages/babel-parser/test/fixtures/typescript/export/equals-in-unambiguous/options.json
@@ -0,0 +1,3 @@
+{
+  "sourceType": "unambiguous"
+}
diff --git a/packages/babel-parser/test/fixtures/typescript/export/equals-in-unambiguous/output.json b/packages/babel-parser/test/fixtures/typescript/export/equals-in-unambiguous/output.json
@@ -0,0 +1,22 @@
+{
+  "type": "File",
+  "start":0,"end":11,"loc":{"start":{"line":1,"column":0,"index":0},"end":{"line":1,"column":11,"index":11}},
+  "program": {
+    "type": "Program",
+    "start":0,"end":11,"loc":{"start":{"line":1,"column":0,"index":0},"end":{"line":1,"column":11,"index":11}},
+    "sourceType": "module",
+    "interpreter": null,
+    "body": [
+      {
+        "type": "TSExportAssignment",
+        "start":0,"end":11,"loc":{"start":{"line":1,"column":0,"index":0},"end":{"line":1,"column":11,"index":11}},
+        "expression": {
+          "type": "Identifier",
+          "start":9,"end":10,"loc":{"start":{"line":1,"column":9,"index":9},"end":{"line":1,"column":10,"index":10},"identifierName":"f"},
+          "name": "f"
+        }
+      }
+    ],
+    "directives": []
+  }
+}
diff --git a/packages/babel-parser/test/fixtures/typescript/import/equals-in-script/input.ts b/packages/babel-parser/test/fixtures/typescript/import/equals-in-script/input.ts
@@ -0,0 +1 @@
+import A = B.C;
diff --git a/packages/babel-parser/test/fixtures/typescript/import/equals-in-script/options.json b/packages/babel-parser/test/fixtures/typescript/import/equals-in-script/options.json
@@ -0,0 +1,3 @@
+{
+    "sourceType": "script"
+}
diff --git a/packages/babel-parser/test/fixtures/typescript/import/equals-in-script/output.json b/packages/babel-parser/test/fixtures/typescript/import/equals-in-script/output.json
@@ -0,0 +1,41 @@
+{
+  "type": "File",
+  "start":0,"end":15,"loc":{"start":{"line":1,"column":0,"index":0},"end":{"line":1,"column":15,"index":15}},
+  "errors": [
+    "SyntaxError: 'import' and 'export' may appear only with 'sourceType: \"module\"' (1:0)"
+  ],
+  "program": {
+    "type": "Program",
+    "start":0,"end":15,"loc":{"start":{"line":1,"column":0,"index":0},"end":{"line":1,"column":15,"index":15}},
+    "sourceType": "script",
+    "interpreter": null,
+    "body": [
+      {
+        "type": "TSImportEqualsDeclaration",
+        "start":0,"end":15,"loc":{"start":{"line":1,"column":0,"index":0},"end":{"line":1,"column":15,"index":15}},
+        "importKind": "value",
+        "isExport": false,
+        "id": {
+          "type": "Identifier",
+          "start":7,"end":8,"loc":{"start":{"line":1,"column":7,"index":7},"end":{"line":1,"column":8,"index":8},"identifierName":"A"},
+          "name": "A"
+        },
+        "moduleReference": {
+          "type": "TSQualifiedName",
+          "start":11,"end":14,"loc":{"start":{"line":1,"column":11,"index":11},"end":{"line":1,"column":14,"index":14}},
+          "left": {
+            "type": "Identifier",
+            "start":11,"end":12,"loc":{"start":{"line":1,"column":11,"index":11},"end":{"line":1,"column":12,"index":12},"identifierName":"B"},
+            "name": "B"
+          },
+          "right": {
+            "type": "Identifier",
+            "start":13,"end":14,"loc":{"start":{"line":1,"column":13,"index":13},"end":{"line":1,"column":14,"index":14},"identifierName":"C"},
+            "name": "C"
+          }
+        }
+      }
+    ],
+    "directives": []
+  }
+}
diff --git a/packages/babel-parser/test/fixtures/typescript/import/equals-in-unambiguous/input.ts b/packages/babel-parser/test/fixtures/typescript/import/equals-in-unambiguous/input.ts
@@ -0,0 +1 @@
+import A = B.C;
diff --git a/packages/babel-parser/test/fixtures/typescript/import/equals-in-unambiguous/options.json b/packages/babel-parser/test/fixtures/typescript/import/equals-in-unambiguous/options.json
@@ -0,0 +1,3 @@
+{
+    "sourceType": "unambiguous"
+}
diff --git a/packages/babel-parser/test/fixtures/typescript/import/equals-in-unambiguous/output.json b/packages/babel-parser/test/fixtures/typescript/import/equals-in-unambiguous/output.json
@@ -0,0 +1,38 @@
+{
+  "type": "File",
+  "start":0,"end":15,"loc":{"start":{"line":1,"column":0,"index":0},"end":{"line":1,"column":15,"index":15}},
+  "program": {
+    "type": "Program",
+    "start":0,"end":15,"loc":{"start":{"line":1,"column":0,"index":0},"end":{"line":1,"column":15,"index":15}},
+    "sourceType": "script",
+    "interpreter": null,
+    "body": [
+      {
+        "type": "TSImportEqualsDeclaration",
+        "start":0,"end":15,"loc":{"start":{"line":1,"column":0,"index":0},"end":{"line":1,"column":15,"index":15}},
+        "importKind": "value",
+        "isExport": false,
+        "id": {
+          "type": "Identifier",
+          "start":7,"end":8,"loc":{"start":{"line":1,"column":7,"index":7},"end":{"line":1,"column":8,"index":8},"identifierName":"A"},
+          "name": "A"
+        },
+        "moduleReference": {
+          "type": "TSQualifiedName",
+          "start":11,"end":14,"loc":{"start":{"line":1,"column":11,"index":11},"end":{"line":1,"column":14,"index":14}},
+          "left": {
+            "type": "Identifier",
+            "start":11,"end":12,"loc":{"start":{"line":1,"column":11,"index":11},"end":{"line":1,"column":12,"index":12},"identifierName":"B"},
+            "name": "B"
+          },
+          "right": {
+            "type": "Identifier",
+            "start":13,"end":14,"loc":{"start":{"line":1,"column":13,"index":13},"end":{"line":1,"column":14,"index":14},"identifierName":"C"},
+            "name": "C"
+          }
+        }
+      }
+    ],
+    "directives": []
+  }
+}
diff --git a/packages/babel-parser/test/fixtures/typescript/import/equals-require-in-script/input.ts b/packages/babel-parser/test/fixtures/typescript/import/equals-require-in-script/input.ts
@@ -0,0 +1 @@
+import a = require("a");
diff --git a/packages/babel-parser/test/fixtures/typescript/import/equals-require-in-script/options.json b/packages/babel-parser/test/fixtures/typescript/import/equals-require-in-script/options.json
@@ -0,0 +1,3 @@
+{
+    "sourceType": "script"
+}
diff --git a/packages/babel-parser/test/fixtures/typescript/import/equals-require-in-script/output.json b/packages/babel-parser/test/fixtures/typescript/import/equals-require-in-script/output.json
@@ -0,0 +1,40 @@
+{
+  "type": "File",
+  "start":0,"end":24,"loc":{"start":{"line":1,"column":0,"index":0},"end":{"line":1,"column":24,"index":24}},
+  "errors": [
+    "SyntaxError: 'import' and 'export' may appear only with 'sourceType: \"module\"' (1:0)"
+  ],
+  "program": {
+    "type": "Program",
+    "start":0,"end":24,"loc":{"start":{"line":1,"column":0,"index":0},"end":{"line":1,"column":24,"index":24}},
+    "sourceType": "script",
+    "interpreter": null,
+    "body": [
+      {
+        "type": "TSImportEqualsDeclaration",
+        "start":0,"end":24,"loc":{"start":{"line":1,"column":0,"index":0},"end":{"line":1,"column":24,"index":24}},
+        "importKind": "value",
+        "isExport": false,
+        "id": {
+          "type": "Identifier",
+          "start":7,"end":8,"loc":{"start":{"line":1,"column":7,"index":7},"end":{"line":1,"column":8,"index":8},"identifierName":"a"},
+          "name": "a"
+        },
+        "moduleReference": {
+          "type": "TSExternalModuleReference",
+          "start":11,"end":23,"loc":{"start":{"line":1,"column":11,"index":11},"end":{"line":1,"column":23,"index":23}},
+          "expression": {
+            "type": "StringLiteral",
+            "start":19,"end":22,"loc":{"start":{"line":1,"column":19,"index":19},"end":{"line":1,"column":22,"index":22}},
+            "extra": {
+              "rawValue": "a",
+              "raw": "\"a\""
+            },
+            "value": "a"
+          }
+        }
+      }
+    ],
+    "directives": []
+  }
+}
diff --git a/packages/babel-parser/test/fixtures/typescript/import/equals-require-in-unambiguous/input.ts b/packages/babel-parser/test/fixtures/typescript/import/equals-require-in-unambiguous/input.ts
@@ -0,0 +1 @@
+import a = require("a");
diff --git a/...s/babel-parser/test/fixtures/typescript/import/equals-require-in-unambiguous/options.json b/...s/babel-parser/test/fixtures/typescript/import/equals-require-in-unambiguous/options.json
@@ -0,0 +1,3 @@
+{
+    "sourceType": "unambiguous"
+}
diff --git a/...es/babel-parser/test/fixtures/typescript/import/equals-require-in-unambiguous/output.json b/...es/babel-parser/test/fixtures/typescript/import/equals-require-in-unambiguous/output.json
@@ -0,0 +1,37 @@
+{
+  "type": "File",
+  "start":0,"end":24,"loc":{"start":{"line":1,"column":0,"index":0},"end":{"line":1,"column":24,"index":24}},
+  "program": {
+    "type": "Program",
+    "start":0,"end":24,"loc":{"start":{"line":1,"column":0,"index":0},"end":{"line":1,"column":24,"index":24}},
+    "sourceType": "module",
+    "interpreter": null,
+    "body": [
+      {
+        "type": "TSImportEqualsDeclaration",
+        "start":0,"end":24,"loc":{"start":{"line":1,"column":0,"index":0},"end":{"line":1,"column":24,"index":24}},
+        "importKind": "value",
+        "isExport": false,
+        "id": {
+          "type": "Identifier",
+          "start":7,"end":8,"loc":{"start":{"line":1,"column":7,"index":7},"end":{"line":1,"column":8,"index":8},"identifierName":"a"},
+          "name": "a"
+        },
+        "moduleReference": {
+          "type": "TSExternalModuleReference",
+          "start":11,"end":23,"loc":{"start":{"line":1,"column":11,"index":11},"end":{"line":1,"column":23,"index":23}},
+          "expression": {
+            "type": "StringLiteral",
+            "start":19,"end":22,"loc":{"start":{"line":1,"column":19,"index":19},"end":{"line":1,"column":22,"index":22}},
+            "extra": {
+              "rawValue": "a",
+              "raw": "\"a\""
+            },
+            "value": "a"
+          }
+        }
+      }
+    ],
+    "directives": []
+  }
+}
diff --git a/packages/babel-plugin-transform-typescript/src/index.ts b/packages/babel-plugin-transform-typescript/src/index.ts
@@ -1,6 +1,6 @@
 import { declare } from "@babel/helper-plugin-utils";
 import syntaxTypeScript from "@babel/plugin-syntax-typescript";
-import type { types as t } from "@babel/core";
+import type { PluginPass, types as t } from "@babel/core";
 import { injectInitialization } from "@babel/helper-create-class-features-plugin";
 import type { Binding, NodePath, Scope } from "@babel/traverse";
 import type { Options as SyntaxOptions } from "@babel/plugin-syntax-typescript";
@@ -78,6 +78,22 @@ function safeRemove(path: NodePath) {
   path.opts.noScope = false;
 }
 
+function assertCjsTransformEnabled(
+  path: NodePath,
+  pass: PluginPass,
+  wrong: string,
+  suggestion: string,
+  extra: string = "",
+): void {
+  if (pass.file.get("@babel/plugin-transform-modules-*") !== "commonjs") {
+    throw path.buildCodeFrameError(
+      `\`${wrong}\` is only supported when compiling modules to CommonJS.\n` +
+        `Please consider using \`${suggestion}\`${extra}, or add ` +
+        `@babel/plugin-transform-modules-commonjs to your Babel config.`,
+    );
+  }
+}
+
 export interface Options extends SyntaxOptions {
   /** @default true */
   allowNamespaces?: boolean;
@@ -574,34 +590,48 @@ export default declare((api, opts: Options) => {
         }
       },
 
-      TSImportEqualsDeclaration(path: NodePath<t.TSImportEqualsDeclaration>) {
-        if (t.isTSExternalModuleReference(path.node.moduleReference)) {
+      TSImportEqualsDeclaration(
+        path: NodePath<t.TSImportEqualsDeclaration>,
+        pass,
+      ) {
+        const { id, moduleReference } = path.node;
+
+        let init: t.Expression;
+        let varKind: "var" | "const";
+        if (t.isTSExternalModuleReference(moduleReference)) {
           // import alias = require('foo');
-          throw path.buildCodeFrameError(
-            `\`import ${path.node.id.name} = require('${path.node.moduleReference.expression.value}')\` ` +
-              "is not supported by @babel/plugin-transform-typescript\n" +
-              "Please consider using " +
-              `\`import ${path.node.id.name} from '${path.node.moduleReference.expression.value}';\` alongside ` +
-              "Typescript's --allowSyntheticDefaultImports option.",
+          assertCjsTransformEnabled(
+            path,
+            pass,
+            `import ${id.name} = require(...);`,
+            `import ${id.name} from '...';`,
+            " alongside Typescript's --allowSyntheticDefaultImports option",
           );
+          init = t.callExpression(t.identifier("require"), [
+            moduleReference.expression,
+          ]);
+          varKind = "const";
+        } else {
+          // import alias = Namespace;
+          init = entityNameToExpr(moduleReference);
+          varKind = "var";
         }
 
-        // import alias = Namespace;
         path.replaceWith(
-          t.variableDeclaration("var", [
-            t.variableDeclarator(
-              path.node.id,
-              entityNameToExpr(path.node.moduleReference),
-            ),
-          ]),
+          t.variableDeclaration(varKind, [t.variableDeclarator(id, init)]),
         );
         path.scope.registerDeclaration(path);
       },
 
-      TSExportAssignment(path) {
-        throw path.buildCodeFrameError(
-          "`export =` is not supported by @babel/plugin-transform-typescript\n" +
-            "Please consider using `export <value>;`.",
+      TSExportAssignment(path, pass) {
+        assertCjsTransformEnabled(
+          path,
+          pass,
+          `export = <value>;`,
+          `export default <value>;`,
+        );
+        path.replaceWith(
+          template.statement.ast`module.exports = ${path.node.expression}`,
         );
       },
 

diff --git a/packages/babel-plugin-transform-typescript/test/fixtures/exports/export=-to-cjs/input.ts b/packages/babel-plugin-transform-typescript/test/fixtures/exports/export=-to-cjs/input.ts
@@ -0,0 +1 @@
+export = 0;
diff --git a/packages/babel-plugin-transform-typescript/test/fixtures/exports/export=-to-cjs/options.json b/packages/babel-plugin-transform-typescript/test/fixtures/exports/export=-to-cjs/options.json
@@ -0,0 +1,4 @@
+{
+  "plugins": ["transform-typescript", "transform-modules-commonjs"],
+  "sourceType": "module"
+}
diff --git a/packages/babel-plugin-transform-typescript/test/fixtures/exports/export=-to-cjs/output.js b/packages/babel-plugin-transform-typescript/test/fixtures/exports/export=-to-cjs/output.js
@@ -0,0 +1,3 @@
+"use strict";
+
+module.exports = 0;
diff --git a/packages/babel-plugin-transform-typescript/test/fixtures/exports/export=/options.json b/packages/babel-plugin-transform-typescript/test/fixtures/exports/export=/options.json
@@ -1,3 +1,3 @@
 {
-  "throws": "`export =` is not supported by @babel/plugin-transform-typescript\nPlease consider using `export <value>;`."
+  "throws": "`export = <value>;` is only supported when compiling modules to CommonJS.\nPlease consider using `export default <value>;`, or add @babel/plugin-transform-modules-commonjs to your Babel config."
 }
diff --git a/...pt/test/fixtures/imports/import=/input.ts → ...es/imports/import=-module-to-cjs/input.ts b/...pt/test/fixtures/imports/import=/input.ts → ...es/imports/import=-module-to-cjs/input.ts
diff --git a/...abel-plugin-transform-typescript/test/fixtures/imports/import=-module-to-cjs/options.json b/...abel-plugin-transform-typescript/test/fixtures/imports/import=-module-to-cjs/options.json
@@ -0,0 +1,4 @@
+{
+  "plugins": ["transform-typescript", "transform-modules-commonjs"],
+  "sourceType": "module"
+}
diff --git a/...s/babel-plugin-transform-typescript/test/fixtures/imports/import=-module-to-cjs/output.js b/...s/babel-plugin-transform-typescript/test/fixtures/imports/import=-module-to-cjs/output.js
@@ -0,0 +1,4 @@
+"use strict";
+
+const lib = require("lib");
+lib();
diff --git a/packages/babel-plugin-transform-typescript/test/fixtures/imports/import=-module/input.ts b/packages/babel-plugin-transform-typescript/test/fixtures/imports/import=-module/input.ts
@@ -0,0 +1,2 @@
+import lib = require("lib");
+lib();
diff --git a/packages/babel-plugin-transform-typescript/test/fixtures/imports/import=-module/options.json b/packages/babel-plugin-transform-typescript/test/fixtures/imports/import=-module/options.json
@@ -0,0 +1,4 @@
+{
+  "sourceType": "module",
+  "throws": "`import lib = require(...);` is only supported when compiling modules to CommonJS.\nPlease consider using `import lib from '...';` alongside Typescript's --allowSyntheticDefaultImports option, or add @babel/plugin-transform-modules-commonjs to your Babel config."
+}