don't mask encoding errors when decoding a string #6289
diff --git a/Lib/test/test_coding.py b/Lib/test/test_coding.py
index e83015e..7ac3af0 100644
--- a/Lib/test/test_coding.py
+++ b/Lib/test/test_coding.py
@@ -21,6 +21,18 @@
         fp.close()
         self.assertRaises(SyntaxError, compile, text, filename, 'exec')
 
+    def test_error_from_string(self):
+        # See http://bugs.python.org/issue6289
+        input = u"# coding: ascii\n\N{SNOWMAN}".encode('utf-8')
+        try:
+            compile(input, "<string>", "exec")
+        except SyntaxError as e:
+            expected = "'ascii' codec can't decode byte 0xe2 in position 16: " \
+                "ordinal not in range(128)"
+            self.assertTrue(str(e).startswith(expected))
+        else:
+            self.fail("didn't raise")
+
 def test_main():
     test.test_support.run_unittest(CodingTest)