Fix deprecated JSDoc tags not showing for default imports

.github/copilot-questions.md

@@ -1,4 +1,5 @@
-Questions I have that I think the developers of this project can help me with:
- * How does control flow analysis represent a circular graph? I checked the documentation server for "cfa" and "control flow"
- * How do I tell if a symbol is in the global scope? I checked the documentation server for topics referencing "symbol" and "global"
- * What is an `EscapedName`, exactly?
+Questions I have that I think the developers of this project can help me with:
+ * How does control flow analysis represent a circular graph? I checked the documentation server for "cfa" and "control flow"
+ * How do I tell if a symbol is in the global scope? I checked the documentation server for topics referencing "symbol" and "global"
+ * What is an `EscapedName`, exactly?
+ * How to extract JSDoc from export assignments for default exports? I searched the documentation server for "export assignment JSDoc", "default export documentation", "getJSDocCommentsAndTags export", and "symbol display alias JSDoc" but couldn't find specific guidance on retrieving JSDoc comments from export assignment nodes when processing default import symbols.

src/services/symbolDisplay.ts

@@ -20,15 +20,16 @@ import {
     getCombinedLocalAndExportSymbolFlags,
     getDeclarationOfKind,
     getExternalModuleImportEqualsDeclarationExpression,
-    getMeaningFromLocation,
-    getNameOfDeclaration,
-    getNodeModifiers,
-    getObjectFlags,
-    getParseTreeNode,
-    getSourceFileOfNode,
-    getTextOfConstantValue,
-    getTextOfIdentifierOrLiteral,
-    getTextOfNode,
+    getMeaningFromLocation,
+    getNameOfDeclaration,
+    getNodeModifiers,
+    getObjectFlags,
+    getParseTreeNode,
+    getSourceFileOfNode,
+    getTextOfConstantValue,
+    getTextOfIdentifierOrLiteral,
+    getTextOfNode,
+    getJSDocCommentsAndTags,
     hasSyntacticModifier,
     idText,
     ImportEqualsDeclaration,
@@ -48,8 +49,10 @@ import {
     isFunctionBlock,
     isFunctionExpression,
     isFunctionLike,
-    isIdentifier,
-    isInExpressionContext,
+    isIdentifier,
+    isInExpressionContext,
+    isJSDoc,
+    isJSDocDeprecatedTag,
     isJsxOpeningLikeElement,
     isLet,
     isModuleWithStringLiteralName,
@@ -268,7 +271,7 @@ function getSymbolDisplayPartsDocumentationAndSymbolKindWorker(
     alias?: Symbol,
     maximumLength?: number,
     verbosityLevel?: number,
-): SymbolDisplayPartsDocumentationAndSymbolKind {
+): SymbolDisplayPartsDocumentationAndSymbolKind {
     const displayParts: SymbolDisplayPart[] = [];
     let documentation: SymbolDisplayPart[] = [];
     let tags: JSDocTagInfo[] = [];
@@ -583,9 +586,9 @@ function getSymbolDisplayPartsDocumentationAndSymbolKindWorker(
             }
         }
     }
-    // don't use symbolFlags since getAliasedSymbol requires the flag on the symbol itself
-    if (symbol.flags & SymbolFlags.Alias) {
-        prefixNextMeaning();
+    // don't use symbolFlags since getAliasedSymbol requires the flag on the symbol itself
+    if (symbol.flags & SymbolFlags.Alias) {
+        prefixNextMeaning();
         if (!hasAddedSymbolInfo || documentation.length === 0 && tags.length === 0) {
             const resolvedSymbol = typeChecker.getAliasedSymbol(symbol);
             if (resolvedSymbol !== symbol && resolvedSymbol.declarations && resolvedSymbol.declarations.length > 0) {
@@ -615,9 +618,72 @@ function getSymbolDisplayPartsDocumentationAndSymbolKindWorker(
                         typeWriterOut.canIncreaseExpansionDepth = true;
                     }
                 }
-                else {
-                    documentationFromAlias = resolvedSymbol.getContextualDocumentationComment(resolvedNode, typeChecker);
-                    tagsFromAlias = resolvedSymbol.getJsDocTags(typeChecker);
+                else {
+                    documentationFromAlias = resolvedSymbol.getContextualDocumentationComment(resolvedNode, typeChecker);
+                    tagsFromAlias = resolvedSymbol.getJsDocTags(typeChecker);
+                }
+
+                // For default imports, also try to get JSDoc from the corresponding export assignment
+                // Default imports have Alias flag but not ExportValue flag
+                if ((symbol.flags & SymbolFlags.Alias) && !(symbol.flags & SymbolFlags.ExportValue)) {
+                    const sourceFile = getSourceFileOfNode(resolvedNode);
+                    // Find export assignment that exports the resolved symbol as default
+                    for (const statement of sourceFile.statements) {
+                        if (statement.kind === SyntaxKind.ExportAssignment && !(statement as ExportAssignment).isExportEquals) {
+                            const exportAssignment = statement as ExportAssignment;
+                            if (isIdentifier(exportAssignment.expression)) {
+                                const exportedSymbol = typeChecker.getSymbolAtLocation(exportAssignment.expression);
+                                if (exportedSymbol === resolvedSymbol) {
+                                    // Found the export assignment, get its JSDoc directly from the node
+                                    const jsDocCommentsAndTags = getJSDocCommentsAndTags(exportAssignment);
+                                    if (jsDocCommentsAndTags.length > 0) {
+                                        const exportDoc: SymbolDisplayPart[] = [];
+                                        const exportTags: JSDocTagInfo[] = [];
+
+                                        for (const jsDocOrTag of jsDocCommentsAndTags) {
+                                            if (isJSDoc(jsDocOrTag)) {
+                                                // Extract documentation from JSDoc comment
+                                                if (jsDocOrTag.comment) {
+                                                    const commentText = typeof jsDocOrTag.comment === "string" 
+                                                        ? jsDocOrTag.comment 
+                                                        : jsDocOrTag.comment.map(c => c.text || "").join("");
+                                                    if (commentText) {
+                                                        exportDoc.push({ text: commentText, kind: "text" });
+                                                    }
+                                                }
+
+                                                // Extract tags from JSDoc
+                                                if (jsDocOrTag.tags) {
+                                                    for (const tag of jsDocOrTag.tags) {
+                                                        if (isJSDocDeprecatedTag(tag)) {
+                                                            const tagText = tag.comment 
+                                                                ? (typeof tag.comment === "string" 
+                                                                    ? tag.comment 
+                                                                    : tag.comment.map(c => c.text || "").join(""))
+                                                                : undefined;
+                                                            exportTags.push({
+                                                                name: "deprecated",
+                                                                text: tagText ? [{ text: tagText, kind: "text" }] : undefined
+                                                            });
+                                                        }
+                                                    }
+                                                }
+                                            }
+                                        }
+
+                                        // Use export assignment JSDoc if it exists, overriding resolved symbol JSDoc
+                                        if (exportDoc.length > 0) {
+                                            documentationFromAlias = exportDoc;
+                                        }
+                                        if (exportTags.length > 0) {
+                                            tagsFromAlias = exportTags;
+                                        }
+                                    }
+                                    break;
+                                }
+                            }
+                        }
+                    }
                 }
             }
         }

tests/cases/fourslash/quickInfoDeprecatedDefaultExport.ts

@@ -0,0 +1,20 @@
+/// <reference path="fourslash.ts" />
+
+//// @Filename: mod.ts
+//// /** @deprecated please don't use this */
+//// export const depr = 'deprecated';
+//// 
+//// /** Please use this one */
+//// export const notDeprecated = 'not deprecated';
+//// 
+//// /** @deprecated please import { notDeprecated } instead */
+//// export default notDeprecated;
+
+//// @Filename: index.ts
+//// import defaultExport/*0*/, { depr, notDeprecated } from './mod.js';
+//// 
+//// console.log(defaultExport/*1*/);
+//// console.log(depr/*2*/);
+//// console.log(notDeprecated/*3*/);
+
+verify.baselineQuickInfo();