From 320e628a6d98ef5689a239f546cdb20ecccd8dc7 Mon Sep 17 00:00:00 2001
From: Oleksandr T <oleksandr.tarasiuk@outlook.com>
Date: Tue, 9 May 2023 02:55:04 +0300
Subject: [PATCH] fix(53424): in code documentation is not working upon import
 if function expression reuse function type (#53964)

---
 src/services/symbolDisplay.ts                 |  5 +-
 .../reference/quickInfoJsDocAlias.baseline    | 91 +++++++++++++++++++
 tests/cases/fourslash/quickInfoJsDocAlias.ts  | 15 +++
 3 files changed, 108 insertions(+), 3 deletions(-)
 create mode 100644 tests/baselines/reference/quickInfoJsDocAlias.baseline
 create mode 100644 tests/cases/fourslash/quickInfoJsDocAlias.ts

diff --git a/src/services/symbolDisplay.ts b/src/services/symbolDisplay.ts
index 25c04c712f5..f9db3831f3b 100644
--- a/src/services/symbolDisplay.ts
+++ b/src/services/symbolDisplay.ts
@@ -535,12 +535,12 @@ export function getSymbolDisplayPartsDocumentationAndSymbolKind(typeChecker: Typ
     // don't use symbolFlags since getAliasedSymbol requires the flag on the symbol itself
     if (symbol.flags & SymbolFlags.Alias) {
         prefixNextMeaning();
-        if (!hasAddedSymbolInfo) {
+        if (!hasAddedSymbolInfo || documentation.length === 0 && tags.length === 0) {
             const resolvedSymbol = typeChecker.getAliasedSymbol(symbol);
             if (resolvedSymbol !== symbol && resolvedSymbol.declarations && resolvedSymbol.declarations.length > 0) {
                 const resolvedNode = resolvedSymbol.declarations[0];
                 const declarationName = getNameOfDeclaration(resolvedNode);
-                if (declarationName) {
+                if (declarationName && !hasAddedSymbolInfo) {
                     const isExternalModuleDeclaration =
                         isModuleWithStringLiteralName(resolvedNode) &&
                         hasSyntacticModifier(resolvedNode, ModifierFlags.Ambient);
@@ -835,7 +835,6 @@ export function getSymbolDisplayPartsDocumentationAndSymbolKind(typeChecker: Typ
             documentation = allSignatures[0].getDocumentationComment(typeChecker);
             tags = allSignatures[0].getJsDocTags().filter(tag => tag.name !== "deprecated"); // should only include @deprecated JSDoc tag on the first overload (#49368)
         }
-
     }
 
     function writeTypeParametersOfSymbol(symbol: Symbol, enclosingDeclaration: Node | undefined) {
diff --git a/tests/baselines/reference/quickInfoJsDocAlias.baseline b/tests/baselines/reference/quickInfoJsDocAlias.baseline
new file mode 100644
index 00000000000..8fbd9b68665
--- /dev/null
+++ b/tests/baselines/reference/quickInfoJsDocAlias.baseline
@@ -0,0 +1,91 @@
+=== /b.ts ===
+// import { A } from "./a";
+// A()
+// ^
+// | ----------------------------------------------------------------------
+// | (alias) A(): void
+// | import A
+// | docs - const A: T
+// | ----------------------------------------------------------------------
+
+[
+  {
+    "marker": {
+      "fileName": "/b.ts",
+      "position": 26,
+      "name": ""
+    },
+    "item": {
+      "kind": "alias",
+      "kindModifiers": "export,declare",
+      "textSpan": {
+        "start": 25,
+        "length": 1
+      },
+      "displayParts": [
+        {
+          "text": "(",
+          "kind": "punctuation"
+        },
+        {
+          "text": "alias",
+          "kind": "text"
+        },
+        {
+          "text": ")",
+          "kind": "punctuation"
+        },
+        {
+          "text": " ",
+          "kind": "space"
+        },
+        {
+          "text": "A",
+          "kind": "aliasName"
+        },
+        {
+          "text": "(",
+          "kind": "punctuation"
+        },
+        {
+          "text": ")",
+          "kind": "punctuation"
+        },
+        {
+          "text": ":",
+          "kind": "punctuation"
+        },
+        {
+          "text": " ",
+          "kind": "space"
+        },
+        {
+          "text": "void",
+          "kind": "keyword"
+        },
+        {
+          "text": "\n",
+          "kind": "lineBreak"
+        },
+        {
+          "text": "import",
+          "kind": "keyword"
+        },
+        {
+          "text": " ",
+          "kind": "space"
+        },
+        {
+          "text": "A",
+          "kind": "aliasName"
+        }
+      ],
+      "documentation": [
+        {
+          "text": "docs - const A: T",
+          "kind": "text"
+        }
+      ]
+    }
+  }
+]
\ No newline at end of file
diff --git a/tests/cases/fourslash/quickInfoJsDocAlias.ts b/tests/cases/fourslash/quickInfoJsDocAlias.ts
new file mode 100644
index 00000000000..607f8c35a14
--- /dev/null
+++ b/tests/cases/fourslash/quickInfoJsDocAlias.ts
@@ -0,0 +1,15 @@
+/// <reference path="fourslash.ts" />
+
+// @filename: /a.d.ts
+/////** docs - type T */
+////export type T = () => void;
+/////**
+//// * docs - const A: T
+//// */
+////export declare const A: T;
+
+// @filename: /b.ts
+////import { A } from "./a";
+////A/**/()
+
+verify.baselineQuickInfo();