refactor(oxlint-plugin): consolidate two copies of isAstDescendant

The 7-line helper that walks an AST parent chain to test ancestor
membership was duplicated byte-identical in:

- rules/react-builtins/exhaustive-deps-symbol-stability.ts
- semantic/closure-captures.ts

Promote to utils/is-ast-descendant.ts. Both callsites now import.

Behaviour-neutral.

Co-authored-by: Aiden Bai <aidenybai@users.noreply.github.com>

Author: cursoragent

packages/oxlint-plugin-react-doctor/src/plugin/rules/react-builtins/exhaustive-deps-symbol-stability.ts

@@ -3,6 +3,7 @@ import type { ScopeAnalysis, SymbolDescriptor } from "../../semantic/scope-analy
 import type { EsTreeNode } from "../../utils/es-tree-node.js";
 import type { EsTreeNodeOfType } from "../../utils/es-tree-node-of-type.js";
 import { getStaticTemplateLiteralValue } from "../../utils/get-static-template-literal-value.js";
+import { isAstDescendant } from "../../utils/is-ast-descendant.js";
 import { isNodeOfType } from "../../utils/is-node-of-type.js";
 import {
   getHookName,
@@ -122,15 +123,6 @@ export const getFunctionValueNode = (symbol: SymbolDescriptor): EsTreeNode | nul
   return null;
 };
 
-const isAstDescendant = (inner: EsTreeNode, outer: EsTreeNode): boolean => {
-  let current: EsTreeNode | null | undefined = inner;
-  while (current) {
-    if (current === outer) return true;
-    current = current.parent ?? null;
-  }
-  return false;
-};
-
 export const isRecursiveInitializerCapture = (
   symbol: SymbolDescriptor,
   callback: EsTreeNode,

packages/oxlint-plugin-react-doctor/src/plugin/semantic/closure-captures.ts

@@ -1,6 +1,7 @@
 import type { EsTreeNode } from "../utils/es-tree-node.js";
 import type { ReferenceDescriptor, ScopeAnalysis } from "./scope-analysis.js";
 import { isDescendantScope } from "./scope-analysis.js";
+import { isAstDescendant } from "../utils/is-ast-descendant.js";
 import { isAstNode } from "../utils/is-ast-node.js";
 import { isFunctionLike } from "../utils/is-function-like.js";
 
@@ -15,15 +16,6 @@ const TYPE_ONLY_CHILD_KEYS: ReadonlySet<string> = new Set([
 
 // True if `inner` is a descendant of `outer` (or equal) in the AST
 // tree. Used to filter references inside `functionNode`.
-const isAstDescendant = (inner: EsTreeNode, outer: EsTreeNode): boolean => {
-  let current: EsTreeNode | null | undefined = inner;
-  while (current) {
-    if (current === outer) return true;
-    current = current.parent ?? null;
-  }
-  return false;
-};
-
 // Returns every reference inside `functionNode`'s body whose binding
 // lives OUTSIDE the function — i.e. the closure-captured set. Useful
 // for exhaustive-deps to compute the actual set of values a hook

packages/oxlint-plugin-react-doctor/src/plugin/utils/is-ast-descendant.ts

@@ -0,0 +1,19 @@
+import type { EsTreeNode } from "./es-tree-node.js";
+
+/**
+ * True when `inner` is `outer` itself or any descendant in the AST
+ * `parent` chain. Walks `inner.parent` upward and stops at either a
+ * match (`true`) or the chain's root (`false`).
+ *
+ * Was duplicated byte-identical in:
+ * - exhaustive-deps-symbol-stability.ts
+ * - semantic/closure-captures.ts
+ */
+export const isAstDescendant = (inner: EsTreeNode, outer: EsTreeNode): boolean => {
+  let current: EsTreeNode | null | undefined = inner;
+  while (current) {
+    if (current === outer) return true;
+    current = current.parent ?? null;
+  }
+  return false;
+};