From 44a2971e5c7d474b9a5c57fdd916281cd93609ec Mon Sep 17 00:00:00 2001
From: Daniel Pepper <pepper.daniel@gmail.com>
Date: Tue, 11 Jan 2022 16:47:01 -0800
Subject: [PATCH] atomic write race condition

---
 activesupport/CHANGELOG.md                               | 2 ++
 activesupport/lib/active_support/core_ext/file/atomic.rb | 2 ++
 activesupport/test/core_ext/file_test.rb                 | 4 ++++
 3 files changed, 8 insertions(+)

diff --git a/activesupport/CHANGELOG.md b/activesupport/CHANGELOG.md
index a9c06b71445..c35a3597305 100644
--- a/activesupport/CHANGELOG.md
+++ b/activesupport/CHANGELOG.md
@@ -1,3 +1,5 @@
+*   Improve `File.atomic_write` error handling
+
 *   Fix `Class#descendants` and `DescendantsTracker#descendants` compatibility with Ruby 3.1.
 
     [The native `Class#descendants` was reverted prior to Ruby 3.1 release](https://bugs.ruby-lang.org/issues/14394#note-33),
diff --git a/activesupport/lib/active_support/core_ext/file/atomic.rb b/activesupport/lib/active_support/core_ext/file/atomic.rb
index 28b72ed42fc..b442ea3100f 100644
--- a/activesupport/lib/active_support/core_ext/file/atomic.rb
+++ b/activesupport/lib/active_support/core_ext/file/atomic.rb
@@ -64,6 +64,8 @@ class File
     file_name = join(dir, basename)
     FileUtils.touch(file_name)
     stat(file_name)
+  rescue Errno::ENOENT
+    file_name = nil
   ensure
     FileUtils.rm_f(file_name) if file_name
   end
diff --git a/activesupport/test/core_ext/file_test.rb b/activesupport/test/core_ext/file_test.rb
index b9d4c11d80c..314d38c5918 100644
--- a/activesupport/test/core_ext/file_test.rb
+++ b/activesupport/test/core_ext/file_test.rb
@@ -83,6 +83,10 @@ class AtomicWriteTest < ActiveSupport::TestCase
     File.unlink(file_name) rescue nil
   end
 
+  def test_probe_stat_in_when_no_dir
+    assert_nil File.probe_stat_in("/dir/does/not/exist")
+  end
+
   private
     def file_name
       "atomic-#{Process.pid}.file"