fs: remove unnecessary argument check

Writable already assures that only Buffer's are passed to _write. Also
this is not the "correct" way to handle errors inside _write.

PR-URL: https://github.com/nodejs/node/pull/29043
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Rich Trott <rtrott@gmail.com>

1 files changed, 3 insertions, 6 deletions

diff --git a/lib/internal/fs/streams.js b/lib/internal/fs/streams.js
index b0c4224893..110ad11493 100644
--- a/lib/internal/fs/streams.js
+++ b/lib/internal/fs/streams.js
@@ -3,7 +3,6 @@
 const { Math, Object } = primordials;
 
 const {
-  ERR_INVALID_ARG_TYPE,
   ERR_OUT_OF_RANGE
 } = require('internal/errors').codes;
 const { validateNumber } = require('internal/validators');
@@ -235,6 +234,9 @@ function WriteStream(path, options) {
 
   options = copyObject(getOptions(options, {}));
 
+  // Only buffers are supported.
+  options.decodeStrings = true;
+
   // For backwards compat do not emit close on destroy.
   if (options.emitClose === undefined) {
     options.emitClose = false;
@@ -295,11 +297,6 @@ WriteStream.prototype.open = function() {
 
 
 WriteStream.prototype._write = function(data, encoding, cb) {
-  if (!(data instanceof Buffer)) {
-    const err = new ERR_INVALID_ARG_TYPE('data', 'Buffer', data);
-    return this.emit('error', err);
-  }
-
   if (typeof this.fd !== 'number') {
     return this.once('open', function() {
       this._write(data, encoding, cb);