diff --git a/Library/Homebrew/extend/fileutils.rb b/Library/Homebrew/extend/fileutils.rb
index 8b8d21da4dd98..4f20d36a3bd9d 100644
--- a/Library/Homebrew/extend/fileutils.rb
+++ b/Library/Homebrew/extend/fileutils.rb
@@ -88,7 +88,7 @@ def run
 
   # A version of mkdir that also changes to that folder in a block.
   def mkdir(name, &_block)
-    old_mkdir(name)
+    mkdir_p(name)
     return unless block_given?
     chdir name do
       yield
diff --git a/Library/Homebrew/test/test_pathname.rb b/Library/Homebrew/test/test_pathname.rb
index 492c09c67a610..2f6360719b030 100644
--- a/Library/Homebrew/test/test_pathname.rb
+++ b/Library/Homebrew/test/test_pathname.rb
@@ -257,4 +257,11 @@ def test_install_relative_symlink
     @dst.install_symlink "foo" => "bar"
     assert_equal Pathname.new("foo"), (@dst/"bar").readlink
   end
+
+  def test_mkdir_creates_intermediate_directories
+    mkdir @dst/"foo/bar/baz" do
+      assert_predicate @dst/"foo/bar/baz", :exist?, "foo/bar/baz was not created"
+      assert_predicate @dst/"foo/bar/baz", :directory?, "foo/bar/baz was not a directory structure"
+    end
+  end
 end