Ensure findPrecedingToken recurses into JSDoc children when needed (#53487)

src/services/utilities.ts

@@ -1739,7 +1739,14 @@ export function findPrecedingToken(position: number, sourceFile: SourceFileLike,
                 if (lookInPreviousChild) {
                     // actual start of the node is past the position - previous token should be at the end of previous child
                     const candidate = findRightmostChildNodeWithTokens(children, /*exclusiveStartPosition*/ i, sourceFile, n.kind);
-                    return candidate && findRightmostToken(candidate, sourceFile);
+                    if (candidate) {
+                        // Ensure we recurse into JSDoc nodes with children.
+                        if (!excludeJsdoc && isJSDocCommentContainingNode(candidate) && candidate.getChildren(sourceFile).length) {
+                            return find(candidate);
+                        }
+                        return findRightmostToken(candidate, sourceFile);
+                    }
+                    return undefined;
                 }
                 else {
                     // candidate should be in this node

src/testRunner/tests.ts

@@ -61,6 +61,7 @@ import "./unittests/services/patternMatcher";
 import "./unittests/services/preProcessFile";
 import "./unittests/services/textChanges";
 import "./unittests/services/transpile";
+import "./unittests/services/utilities";
 import "./unittests/tsbuild/amdModulesWithOut";
 import "./unittests/tsbuild/clean";
 import "./unittests/tsbuild/commandLine";

src/testRunner/unittests/services/utilities.ts

@@ -0,0 +1,20 @@
+import * as ts from "../../_namespaces/ts";
+
+describe("unittests:: services:: utilities", () => {
+    describe("Test findPrecedingMatchingToken,", () => {
+        it("should not infinite loop finding opening brace", () => {
+            const sourceFile = ts.createSourceFile("file.ts", `/// <reference path="./compiler.d.ts" />
+
+(/** @window => {
+  /** @type {Abcd123} */
+  const core = window.Abcd.core;
+})();`, ts.ScriptTarget.ESNext, /*setParentNodes*/ true);
+            // can't use ts.getTokenAtPosition because it returns back the wrong token
+            const param = ts.forEachChildRecursively(sourceFile, node => node.kind === ts.SyntaxKind.Parameter ? node : undefined)!;
+            const jsDoc = param.getChildren()[0];
+            const token = jsDoc.getLastToken()!;
+            const result = ts.findPrecedingMatchingToken(token, ts.SyntaxKind.OpenBraceToken, sourceFile);
+            assert.isDefined(result);
+        });
+    });
+});