lib: deprecate fd usage for fs.truncate(Sync)

PR-URL: https://github.com/nodejs/node/pull/15990
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Trevor Norris <trev.norris@gmail.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>

1 files changed, 14 insertions, 0 deletions

diff --git a/lib/fs.js b/lib/fs.js
index b7a2bbba0c..5668540486 100644
--- a/lib/fs.js
+++ b/lib/fs.js
@@ -63,6 +63,18 @@ const isWindows = process.platform === 'win32';
 const DEBUG = process.env.NODE_DEBUG && /fs/.test(process.env.NODE_DEBUG);
 const errnoException = util._errnoException;
 
+let truncateWarn = true;
+
+function showTruncateDeprecation() {
+  if (truncateWarn) {
+    process.emitWarning(
+      'Using fs.truncate with a file descriptor is deprecated. Please use ' +
+      'fs.ftruncate with a file descriptor instead.',
+      'DeprecationWarning', 'DEP0081');
+    truncateWarn = false;
+  }
+}
+
 function getOptions(options, defaultOptions) {
   if (options === null || options === undefined ||
       typeof options === 'function') {
@@ -783,6 +795,7 @@ fs.renameSync = function(oldPath, newPath) {
 
 fs.truncate = function(path, len, callback) {
   if (typeof path === 'number') {
+    showTruncateDeprecation();
     return fs.ftruncate(path, len, callback);
   }
   if (typeof len === 'function') {
@@ -808,6 +821,7 @@ fs.truncate = function(path, len, callback) {
 fs.truncateSync = function(path, len) {
   if (typeof path === 'number') {
     // legacy
+    showTruncateDeprecation();
     return fs.ftruncateSync(path, len);
   }
   if (len === undefined) {