fix(fs): expose iterator helpers on walk/walkSync and expandGlob/expandGlobSync

fs/expand_glob.ts

@@ -271,7 +271,7 @@ function comparePath(a: WalkEntry, b: WalkEntry): number {
 export async function* expandGlob(
   glob: string | URL,
   options?: ExpandGlobOptions,
-): AsyncIterableIterator<WalkEntry> {
+): AsyncGenerator<WalkEntry> {
   let {
     root,
     exclude = [],
@@ -375,7 +375,9 @@ export async function* expandGlob(
       (entry: WalkEntry): boolean => !entry.isDirectory,
     );
   }
-  yield* currentMatches;
+  for (const match of currentMatches) {
+    yield match;
+  }
 }
 
 /**
@@ -428,7 +430,7 @@ export async function* expandGlob(
 export function* expandGlobSync(
   glob: string | URL,
   options?: ExpandGlobOptions,
-): IterableIterator<WalkEntry> {
+): Generator<WalkEntry> {
   let {
     root,
     exclude = [],
@@ -530,7 +532,9 @@ export function* expandGlobSync(
       (entry: WalkEntry): boolean => !entry.isDirectory,
     );
   }
-  yield* currentMatches;
+  for (const match of currentMatches) {
+    yield match;
+  }
 }
 
 const globEscapeChar =

fs/expand_glob_test.ts

@@ -11,6 +11,7 @@ import {
   expandGlob,
   type ExpandGlobOptions,
   expandGlobSync,
+  type WalkEntry,
 } from "./expand_glob.ts";
 
 async function expandGlobArray(
@@ -464,3 +465,22 @@ Deno.test("expandGlobSync() finds directory with escaped brackets", function ()
     [join("a[b]c", "foo")],
   );
 });
+
+Deno.test("expandGlobSync() preserves the Generator return type", () => {
+  // Regression test for https://github.com/denoland/std/issues/7099:
+  // the return type must be `Generator<WalkEntry>` so the ES2025 iterator
+  // helpers (`.map`, `.filter`, etc.) are exposed at the type level wherever
+  // the host TypeScript lib defines them. `Generator<T>` requires the
+  // `.return()` / `.throw()` methods that `IterableIterator<T>` leaves
+  // optional, so this assignment fails if the return type is widened back
+  // to `IterableIterator<WalkEntry>`.
+  const iter: Generator<WalkEntry> = expandGlobSync("*", EG_OPTIONS);
+  iter.return(undefined);
+});
+
+Deno.test("expandGlob() preserves the AsyncGenerator return type", async () => {
+  // Regression test for https://github.com/denoland/std/issues/7099 — see the
+  // sync counterpart for rationale.
+  const iter: AsyncGenerator<WalkEntry> = expandGlob("*", EG_OPTIONS);
+  await iter.return(undefined);
+});

fs/walk.ts

@@ -449,7 +449,7 @@ export type { WalkEntry };
 export async function* walk(
   root: string | URL,
   options?: WalkOptions,
-): AsyncIterableIterator<WalkEntry> {
+): AsyncGenerator<WalkEntry> {
   let {
     maxDepth = Infinity,
     includeFiles = true,
@@ -878,7 +878,7 @@ export async function* walk(
 export function* walkSync(
   root: string | URL,
   options?: WalkOptions,
-): IterableIterator<WalkEntry> {
+): Generator<WalkEntry> {
   let {
     maxDepth = Infinity,
     includeFiles = true,

fs/walk_test.ts

@@ -1,5 +1,5 @@
 // Copyright 2018-2026 the Deno authors. MIT license.
-import { walk, type WalkOptions, walkSync } from "./walk.ts";
+import { walk, type WalkEntry, type WalkOptions, walkSync } from "./walk.ts";
 import {
   assertArrayIncludes,
   assertEquals,
@@ -338,6 +338,25 @@ Deno.test({
   },
 });
 
+Deno.test("walkSync() preserves the Generator return type", () => {
+  // Regression test for https://github.com/denoland/std/issues/7099:
+  // the return type must be `Generator<WalkEntry>` so the ES2025 iterator
+  // helpers (`.map`, `.filter`, etc.) are exposed at the type level wherever
+  // the host TypeScript lib defines them. `Generator<T>` requires the
+  // `.return()` / `.throw()` methods that `IterableIterator<T>` leaves
+  // optional, so this assignment fails if the return type is widened back
+  // to `IterableIterator<WalkEntry>`.
+  const iter: Generator<WalkEntry> = walkSync(testdataDir);
+  iter.return(undefined);
+});
+
+Deno.test("walk() preserves the AsyncGenerator return type", async () => {
+  // Regression test for https://github.com/denoland/std/issues/7099 — see the
+  // sync counterpart for rationale.
+  const iter: AsyncGenerator<WalkEntry> = walk(testdataDir);
+  await iter.return(undefined);
+});
+
 Deno.test("walk() rejects with `Deno.errors.NotFound` when root is removed during execution", async () => {
   const tempDirPath = await Deno.makeTempDir({
     prefix: "deno_std_walk_",