test: add tests for fs/promises.js fileHandle methods

Working to increase test code coverage for fs/promises.js.
Added tests for fileHandle.appendFile and fileHandle.chmod.

PR-URL: https://github.com/nodejs/node/pull/19605
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Rich Trott <rtrott@gmail.com>

1 files changed, 32 insertions, 0 deletions

diff --git a/test/parallel/test-fs-promises-file-handle-readFile.js b/test/parallel/test-fs-promises-file-handle-readFile.js
new file mode 100644
index 0000000000..9308c29909
--- /dev/null
+++ b/test/parallel/test-fs-promises-file-handle-readFile.js
@@ -0,0 +1,32 @@
+'use strict';
+
+const common = require('../common');
+
+// The following tests validate base functionality for the fs/promises
+// FileHandle.readFile method.
+
+const fs = require('fs');
+const { open } = require('fs/promises');
+const path = require('path');
+const tmpdir = require('../common/tmpdir');
+const assert = require('assert');
+const tmpDir = tmpdir.path;
+
+tmpdir.refresh();
+common.crashOnUnhandledRejection();
+
+async function validateReadFile() {
+  const filePath = path.resolve(tmpDir, 'tmp-read-file.txt');
+  const fileHandle = await open(filePath, 'w+');
+  const buffer = Buffer.from('Hello world'.repeat(100), 'utf8');
+
+  const fd = fs.openSync(filePath, 'w+');
+  fs.writeSync(fd, buffer, 0, buffer.length);
+  fs.closeSync(fd);
+
+  const readFileData = await fileHandle.readFile();
+  assert.deepStrictEqual(buffer, readFileData);
+}
+
+validateReadFile()
+  .then(common.mustCall());