merge revision(s) 56766,56767: [Backport #12925]

	error.c: rb_get_backtrace

	* error.c (rb_get_backtrace): move from eval_error.c to call
  exc_backtrace directly.  [ruby-core:78097] [Bug #12925]

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_2_3@56781 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 47 insertions, 0 deletions

diff --git a/test/ruby/test_exception.rb b/test/ruby/test_exception.rb
index 4a39952465..cd8743216e 100644
--- a/test/ruby/test_exception.rb
+++ b/test/ruby/test_exception.rb
@@ -810,4 +810,51 @@ $stderr = $stdout; raise "\x82\xa0"') do |outs, errs, status|
       end
     end
   end
+
+  def test_undefined_backtrace
+    assert_separately([], "#{<<-"begin;"}\n#{<<-"end;"}")
+    begin;
+      class Exception
+        undef backtrace
+      end
+
+      assert_raise(RuntimeError) {
+        raise RuntimeError, "hello"
+      }
+    end;
+  end
+
+  def test_redefined_backtrace
+    assert_separately([], "#{<<-"begin;"}\n#{<<-"end;"}")
+    begin;
+      $exc = nil
+
+      class Exception
+        undef backtrace
+        def backtrace
+          $exc = self
+        end
+      end
+
+      e = assert_raise(RuntimeError) {
+        raise RuntimeError, "hello"
+      }
+      assert_same(e, $exc)
+    end;
+  end
+
+  def test_wrong_backtrace
+    assert_separately([], "#{<<-"begin;"}\n#{<<-"end;"}")
+    begin;
+      class Exception
+        undef backtrace
+        def backtrace(a)
+        end
+      end
+
+      assert_raise(RuntimeError) {
+        raise RuntimeError, "hello"
+      }
+    end;
+  end
 end