1 files changed, 31 insertions, 0 deletions
diff --git a/tests/test_markdown_lexer.py b/tests/test_markdown_lexer.py
new file mode 100644
index 00000000..16d1f28d
--- /dev/null
+++ b/tests/test_markdown_lexer.py
@@ -0,0 +1,31 @@
+# -*- coding: utf-8 -*-
+"""
+    Pygments regex lexer tests
+    ~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+    :copyright: Copyright 2006-2017 by the Pygments team, see AUTHORS.
+    :license: BSD, see LICENSE for details.
+"""
+import unittest
+
+from pygments.lexers.markup import MarkdownLexer
+
+
+class SameTextTests(unittest.TestCase):
+
+    lexer = MarkdownLexer()
+
+    def assert_same_text(self, text):
+        """Show that lexed markdown does not remove any content. """
+        tokens = list(self.lexer.get_tokens_unprocessed(text))
+        output = ''.join(t[2] for t in tokens)
+        self.assertEqual(text, output)
+
+    def test_code_fence(self):
+        self.assert_same_text(r'```\nfoo\n```\n')
+
+    def test_code_fence_gsm(self):
+        self.assert_same_text(r'```markdown\nfoo\n```\n')
+
+    def test_code_fence_gsm_with_no_lexer(self):
+        self.assert_same_text(r'```invalid-lexer\nfoo\n```\n')