1 files changed, 80 insertions, 0 deletions
diff --git a/testing/web-platform/tests/file-system-access/resources/test-helpers.js b/testing/web-platform/tests/file-system-access/resources/test-helpers.js
new file mode 100644
index 0000000000..893cd19848
--- /dev/null
+++ b/testing/web-platform/tests/file-system-access/resources/test-helpers.js
@@ -0,0 +1,80 @@
+// A special path component meaning "this directory."
+const kCurrentDirectory = '.';
+
+// A special path component meaning "the parent directory."
+const kParentDirectory = '..';
+
+// Array of separators used to separate components in hierarchical paths.
+let kPathSeparators;
+if (navigator.userAgent.includes('Windows NT')) {
+  // Windows uses both '/' and '\' as path separators.
+  kPathSeparators = ['/', '\\'];
+} else {
+  kPathSeparators = ['/'];
+}
+
+async function getFileSize(handle) {
+  const file = await handle.getFile();
+  return file.size;
+}
+
+async function getFileContents(handle) {
+  const file = await handle.getFile();
+  return new Response(file).text();
+}
+
+async function getDirectoryEntryCount(handle) {
+  let result = 0;
+  for await (let entry of handle) {
+    result++;
+  }
+  return result;
+}
+
+async function getSortedDirectoryEntries(handle) {
+  let result = [];
+  for await (let entry of handle.values()) {
+    if (entry.kind === 'directory')
+      result.push(entry.name + '/');
+    else
+      result.push(entry.name);
+  }
+  result.sort();
+  return result;
+}
+
+async function createDirectory(test, name, parent) {
+  const new_dir_handle = await parent.getDirectoryHandle(name, {create: true});
+  test.add_cleanup(async () => {
+    try {
+      await parent.removeEntry(name, {recursive: true});
+    } catch (e) {
+      // Ignore any errors when removing directories, as tests might
+      // have already removed the directory.
+    }
+  });
+  return new_dir_handle;
+}
+
+async function createEmptyFile(test, name, parent) {
+  const handle = await parent.getFileHandle(name, {create: true});
+  test.add_cleanup(async () => {
+    try {
+      await parent.removeEntry(name);
+    } catch (e) {
+      // Ignore any errors when removing files, as tests might already remove
+      // the file.
+    }
+  });
+  // Make sure the file is empty.
+  assert_equals(await getFileSize(handle), 0);
+  return handle;
+}
+
+async function createFileWithContents(test, name, contents, parent) {
+  const handle = await createEmptyFile(test, name, parent);
+  const writer = await handle.createWritable();
+  await writer.write(new Blob([contents]));
+  await writer.close();
+  return handle;
+}