Add File.zero?

lib/fakefs/file.rb

@@ -100,6 +100,14 @@ def self.size?(path)
       end
     end
 
+    def self.zero?(path)
+      if exists?(path) and size(path) == 0
+        true
+      else
+        false
+      end
+    end
+
     def self.const_missing(name)
       RealFile.const_get(name)
     end

test/fakefs_test.rb

@@ -492,6 +492,27 @@ def test_can_check_size_of_empty_file
     assert_nil File.size?("file.txt")
   end
 
+  def test_zero_on_empty_file
+    path = 'file.txt'
+    File.open(path, 'w') do |f|
+      f << ''
+    end
+    assert_equal true, File.zero?(path)
+  end
+
+  def test_zero_on_non_empty_file
+    path = 'file.txt'
+    File.open(path, 'w') do |f|
+      f << 'Not empty'
+    end
+    assert_equal false, File.zero?(path)
+  end
+
+  def test_zero_on_non_existent_file
+    path = 'file_does_not_exist.txt'
+    assert_equal false, File.zero?(path)
+  end
+
   def test_raises_error_on_mtime_if_file_does_not_exist
     assert_raise Errno::ENOENT do
       File.mtime('/path/to/file.txt')