Switch conflicting chdir warning to RuntimeError

The documentation already stated this was an error in one case
(when it was previously a warning).  Describe the other case,
where chdir without block is called inside block passed to chdir.

Fixes [Bug #15661]

1 files changed, 28 insertions, 2 deletions

diff --git a/test/ruby/test_dir.rb b/test/ruby/test_dir.rb
index 13b9c1ddf2..cf18af134c 100644
--- a/test/ruby/test_dir.rb
+++ b/test/ruby/test_dir.rb
@@ -99,8 +99,12 @@ class TestDir < Test::Unit::TestCase
     ENV["HOME"] = @pwd
     Dir.chdir do
       assert_equal(@pwd, Dir.pwd)
-      Dir.chdir(@root)
-      assert_equal(@root, Dir.pwd)
+      assert_raise(RuntimeError) { Dir.chdir(@root) }
+      assert_equal(@pwd, Dir.pwd)
+      Dir.chdir(@root) do
+        assert_equal(@root, Dir.pwd)
+      end
+      assert_equal(@pwd, Dir.pwd)
     end
 
   ensure
@@ -121,6 +125,28 @@ class TestDir < Test::Unit::TestCase
     end
   end
 
+  def test_chdir_conflict
+    @pwd = Dir.pwd
+    q = Queue.new
+    t = Thread.new do
+      q.pop
+      Dir.chdir(@pwd) rescue $!
+    end
+    Dir.chdir(@pwd) do
+      q.push nil
+      assert_instance_of(RuntimeError, t.value)
+    end
+
+    t = Thread.new do
+      q.pop
+      Dir.chdir(@pwd){} rescue $!
+    end
+    Dir.chdir(@pwd) do
+      q.push nil
+      assert_instance_of(RuntimeError, t.value)
+    end
+  end
+
   def test_chroot_nodir
     skip if RUBY_PLATFORM =~ /android/
     assert_raise(NotImplementedError, Errno::ENOENT, Errno::EPERM