Merge pull request #29446 from fuafa/infer-js-doc

fix quick fix infer parameter types from usage in js file

src/services/codefixes/inferFromUsage.ts

@@ -274,7 +274,17 @@ namespace ts.codefix {
             return !!merged;
         }));
         const tag = createJSDocComment(comments.join("\n"), createNodeArray([...(oldTags || emptyArray), ...unmergedNewTags]));
-        changes.insertJsdocCommentBefore(sourceFile, parent, tag);
+        const jsDocNode = parent.kind === SyntaxKind.ArrowFunction ? getJsDocNodeForArrowFunction(parent) : parent;
+        jsDocNode.jsDoc = parent.jsDoc;
+        jsDocNode.jsDocCache = parent.jsDocCache;
+        changes.insertJsdocCommentBefore(sourceFile, jsDocNode, tag);
+    }
+
+    function getJsDocNodeForArrowFunction(signature: ArrowFunction): HasJSDoc {
+        if (signature.parent.kind === SyntaxKind.PropertyDeclaration) {
+            return <HasJSDoc>signature.parent;
+        }
+        return <HasJSDoc>signature.parent.parent;
     }
 
     function tryMergeJsdocTags(oldTag: JSDocTag, newTag: JSDocTag): JSDocTag | undefined {

tests/cases/fourslash/codeFixInferFromUsageArrowJS.ts

@@ -0,0 +1,27 @@
+/// <reference path='fourslash.ts' />
+// @allowJs: true
+// @checkJs: true
+// @noEmit: true
+// @noImplicitAny: true
+// @Filename: test.js
+
+////const foo = x => x.y + 1;
+////class C {
+////    m = x => x.y + 1;
+////}
+
+verify.codeFixAll({
+  fixId: "inferFromUsage",
+  fixAllDescription: "Infer all types from usage",
+  newFileContent:
+`/**
+ * @param {{ y: number; }} x
+ */
+const foo = x => x.y + 1;
+class C {
+    /**
+     * @param {{ y: number; }} x
+     */
+    m = x => x.y + 1;
+}`,
+});