1 files changed, 95 insertions, 0 deletions
diff --git a/dom/webgpu/tests/cts/checkout/src/common/internal/file_loader.ts b/dom/webgpu/tests/cts/checkout/src/common/internal/file_loader.ts
new file mode 100644
index 0000000000..922d6a09dd
--- /dev/null
+++ b/dom/webgpu/tests/cts/checkout/src/common/internal/file_loader.ts
@@ -0,0 +1,95 @@
+import { IterableTestGroup } from '../internal/test_group.js';
+import { assert } from '../util/util.js';
+
+import { parseQuery } from './query/parseQuery.js';
+import { TestQuery } from './query/query.js';
+import { TestSuiteListing } from './test_suite_listing.js';
+import { loadTreeForQuery, TestTree, TestTreeLeaf } from './tree.js';
+
+// A listing file, e.g. either of:
+// - `src/webgpu/listing.ts` (which is dynamically computed, has a Promise<TestSuiteListing>)
+// - `out/webgpu/listing.js` (which is pre-baked, has a TestSuiteListing)
+interface ListingFile {
+  listing: Promise<TestSuiteListing> | TestSuiteListing;
+}
+
+// A .spec.ts file, as imported.
+export interface SpecFile {
+  readonly description: string;
+  readonly g: IterableTestGroup;
+}
+
+export interface ImportInfo {
+  url: string;
+}
+
+interface TestFileLoaderEventMap {
+  import: MessageEvent<ImportInfo>;
+  finish: MessageEvent<void>;
+}
+
+export interface TestFileLoader extends EventTarget {
+  addEventListener<K extends keyof TestFileLoaderEventMap>(
+    type: K,
+    listener: (this: TestFileLoader, ev: TestFileLoaderEventMap[K]) => void,
+    options?: boolean | AddEventListenerOptions
+  ): void;
+  addEventListener(
+    type: string,
+    listener: EventListenerOrEventListenerObject,
+    options?: boolean | AddEventListenerOptions
+  ): void;
+  removeEventListener<K extends keyof TestFileLoaderEventMap>(
+    type: K,
+    listener: (this: TestFileLoader, ev: TestFileLoaderEventMap[K]) => void,
+    options?: boolean | EventListenerOptions
+  ): void;
+  removeEventListener(
+    type: string,
+    listener: EventListenerOrEventListenerObject,
+    options?: boolean | EventListenerOptions
+  ): void;
+}
+
+// Base class for DefaultTestFileLoader and FakeTestFileLoader.
+export abstract class TestFileLoader extends EventTarget {
+  abstract listing(suite: string): Promise<TestSuiteListing>;
+  protected abstract import(path: string): Promise<SpecFile>;
+
+  importSpecFile(suite: string, path: string[]): Promise<SpecFile> {
+    const url = `${suite}/${path.join('/')}.spec.js`;
+    this.dispatchEvent(
+      new MessageEvent<ImportInfo>('import', { data: { url } })
+    );
+    return this.import(url);
+  }
+
+  async loadTree(query: TestQuery, subqueriesToExpand: string[] = []): Promise<TestTree> {
+    const tree = await loadTreeForQuery(
+      this,
+      query,
+      subqueriesToExpand.map(s => {
+        const q = parseQuery(s);
+        assert(q.level >= 2, () => `subqueriesToExpand entries should not be multi-file:\n  ${q}`);
+        return q;
+      })
+    );
+    this.dispatchEvent(new MessageEvent<void>('finish'));
+    return tree;
+  }
+
+  async loadCases(query: TestQuery): Promise<IterableIterator<TestTreeLeaf>> {
+    const tree = await this.loadTree(query);
+    return tree.iterateLeaves();
+  }
+}
+
+export class DefaultTestFileLoader extends TestFileLoader {
+  async listing(suite: string): Promise<TestSuiteListing> {
+    return ((await import(`../../${suite}/listing.js`)) as ListingFile).listing;
+  }
+
+  import(path: string): Promise<SpecFile> {
+    return import(`../../${path}`);
+  }
+}