1 files changed, 73 insertions, 0 deletions
diff --git a/ext/node/polyfills/_fs/_fs_appendFile.ts b/ext/node/polyfills/_fs/_fs_appendFile.ts
new file mode 100644
index 000000000..d47afe81b
--- /dev/null
+++ b/ext/node/polyfills/_fs/_fs_appendFile.ts
@@ -0,0 +1,73 @@
+// Copyright 2018-2023 the Deno authors. All rights reserved. MIT license.
+import {
+  CallbackWithError,
+  isFd,
+  maybeCallback,
+  WriteFileOptions,
+} from "internal:deno_node/polyfills/_fs/_fs_common.ts";
+import { Encodings } from "internal:deno_node/polyfills/_utils.ts";
+import {
+  copyObject,
+  getOptions,
+} from "internal:deno_node/polyfills/internal/fs/utils.mjs";
+import {
+  writeFile,
+  writeFileSync,
+} from "internal:deno_node/polyfills/_fs/_fs_writeFile.ts";
+import { promisify } from "internal:deno_node/polyfills/internal/util.mjs";
+
+/**
+ * TODO: Also accept 'data' parameter as a Node polyfill Buffer type once these
+ * are implemented. See https://github.com/denoland/deno/issues/3403
+ */
+export function appendFile(
+  path: string | number | URL,
+  data: string | Uint8Array,
+  options: Encodings | WriteFileOptions | CallbackWithError,
+  callback?: CallbackWithError,
+) {
+  callback = maybeCallback(callback || options);
+  options = getOptions(options, { encoding: "utf8", mode: 0o666, flag: "a" });
+
+  // Don't make changes directly on options object
+  options = copyObject(options);
+
+  // Force append behavior when using a supplied file descriptor
+  if (!options.flag || isFd(path)) {
+    options.flag = "a";
+  }
+
+  writeFile(path, data, options, callback);
+}
+
+/**
+ * TODO: Also accept 'data' parameter as a Node polyfill Buffer type once these
+ * are implemented. See https://github.com/denoland/deno/issues/3403
+ */
+export const appendFilePromise = promisify(appendFile) as (
+  path: string | number | URL,
+  data: string | Uint8Array,
+  options?: Encodings | WriteFileOptions,
+) => Promise<void>;
+
+/**
+ * TODO: Also accept 'data' parameter as a Node polyfill Buffer type once these
+ * are implemented. See https://github.com/denoland/deno/issues/3403
+ */
+export function appendFileSync(
+  path: string | number | URL,
+  data: string | Uint8Array,
+  options?: Encodings | WriteFileOptions,
+) {
+  options = getOptions(options, { encoding: "utf8", mode: 0o666, flag: "a" });
+
+  // Don't make changes directly on options object
+  options = copyObject(options);
+
+  // Force append behavior when using a supplied file descriptor
+  if (!options.flag || isFd(path)) {
+    options.flag = "a";
+  }
+
+  writeFileSync(path, data, options);
+}