Merge pull request #152 from arethetypeswrong/bundler-missing-export-…

…equals Don’t run MissingExportEquals on ESM implementation files
arethetypeswrong · Feb 21, 2024 · f95f1a4 · f95f1a4
2 parents b596e74 + e38ed65
commit f95f1a4
Show file tree

Hide file tree

Showing 3 changed files with 25 additions and 1 deletion.
diff --git a/.changeset/hot-gorillas-repair.md b/.changeset/hot-gorillas-repair.md
@@ -0,0 +1,5 @@
+---
+"@arethetypeswrong/core": patch
+---
+
+Fix false positive MissingExportEquals that can occur when `--moduleResolution bundler` resolves to ESM JS
diff --git a/packages/core/src/internal/checks/exportDefaultDisagreement.ts b/packages/core/src/internal/checks/exportDefaultDisagreement.ts
@@ -46,7 +46,7 @@ export default defineCheck({
     }
     const implementationSourceFile = host.getSourceFile(implementationFileName)!;
     ts.bindSourceFile(implementationSourceFile, bindOptions);
-    if (!implementationSourceFile.symbol?.exports) {
+    if (!implementationSourceFile.symbol?.exports || implementationSourceFile.externalModuleIndicator) {
       return;
     }
 
@@ -115,6 +115,7 @@ export default defineCheck({
       };
     }
 
+    // TODO: does not account for export *
     const typesHaveNonDefaultValueExport = Array.from(typesSourceFile.symbol.exports.values()).some((s) => {
       if (s.escapedName === "default") {
         return false;

diff --git a/packages/core/test/problems/exportDefaultDisagreement.test.ts b/packages/core/test/problems/exportDefaultDisagreement.test.ts
@@ -262,4 +262,22 @@ var index_default = { a, b };`,
       ),
     );
   });
+
+  test("does not run on ESM", () => {
+    assert(
+      isOk(
+        `export * from 'foo';
+        declare const _default: { Type: string, Schema: string };
+        export default _default;`,
+        `var Type = "Type";
+        var Schema = "Schema";
+        var jsYaml = {
+          Type,
+          Schema
+        };
+        export default jsYaml;
+        export { Type, Schema };`,
+      ),
+    );
+  });
 });