Fix completion of partial identifier inside a JsxExpression (#52572)

Co-authored-by: Karl Kraus <karl.kraus@avantagarde-talents.de>
Co-authored-by: Gabriela Araujo Britto <gabrielaa@microsoft.com>

Author: 3 people

src/services/completions.ts

@@ -2899,7 +2899,8 @@ function getCompletionData(
                     // First case is for `<div foo={true} [||] />` or `<div foo={true} [||] ></div>`,
                     // `parent` will be `{true}` and `previousToken` will be `}`
                     // Second case is for `<div foo={true} t[||] ></div>`
-                    if (previousToken.kind === SyntaxKind.CloseBraceToken || (previousToken.kind === SyntaxKind.Identifier || previousToken.parent.kind === SyntaxKind.JsxAttribute)) {
+                    // Second case must not match for `<div foo={undefine[||]}></div>`
+                    if (previousToken.kind === SyntaxKind.CloseBraceToken || (previousToken.kind === SyntaxKind.Identifier && previousToken.parent.kind === SyntaxKind.JsxAttribute)) {
                         isJsxIdentifierExpected = true;
                     }
                     break;

src/testRunner/tests.ts

@@ -190,4 +190,4 @@ import "./unittests/tsserver/typingsInstaller";
 import "./unittests/tsserver/versionCache";
 import "./unittests/tsserver/watchEnvironment";
 import "./unittests/debugDeprecation";
-import "./unittests/tsserver/inconsistentErrorInEditor";
+import "./unittests/tsserver/inconsistentErrorInEditor";

tests/cases/fourslash/completionsJsxExpression.ts

@@ -0,0 +1,30 @@
+/// <reference path="fourslash.ts" />
+
+// @Filename: /a.tsx
+// @jsx: react
+//// declare namespace JSX {
+////     interface IntrinsicElements {
+////         div: { a: string, b: string }
+////     }
+//// }
+//// const value = "test";
+//// <div a={v/**/} />
+
+verify.completions(
+    {
+        marker: "",
+        isNewIdentifierLocation: false,
+        preferences: {
+            includeCompletionsWithSnippetText: true,
+            includeCompletionsWithInsertText: true,
+            jsxAttributeCompletionStyle: "auto",
+        },
+        includes: {
+            name: "value",
+            kind: "const",
+            kindModifiers: "",
+            sortText: completion.SortText.LocationPriority,
+            insertText: undefined,
+        },
+    },
+);