new test case that shows broken string literal slicing behaviour

tests/run/literalslice.pyx

+__doc__ = u"""
+  >>> test_str(1)
+  b'b'
+
+  >>> test_unicode_ascii(2)
+  u'c'
+  >>> test_unicode(0)
+  u'\u00fc'
+
+  >>> test_int_list(2)
+  3
+  >>> test_str_list(1)
+  b'bcd'
+
+  >>> test_int_tuple(2)
+  3
+  >>> test_str_tuple(0)
+  b'a'
+  >>> test_mix_tuple(1)
+  b'abc'
+  >>> test_mix_tuple(0)
+  1
+"""
+
+import sys
+if sys.version_info[0] < 3:
+    __doc__ = __doc__.replace("  b'", "  '")
+else:
+    __doc__ = __doc__.replace("  u'", "  '")
+
+
+def test_str(n):
+    return "abcd"[n]
+
+def test_unicode_ascii(n):
+    return u"abcd"[n]
+
+def test_unicode(n):
+    return u"\u00fc\u00f6\u00e4"[n]
+
+def test_int_list(n):
+    return [1,2,3,4][n]
+
+def test_str_list(n):
+    return ["a","bcd","efg","xyz"][n]
+
+def test_int_tuple(n):
+    return (1,2,3,4)[n]
+
+def test_str_tuple(n):
+    return ("a","bcd","efg","xyz")[n]
+
+def test_mix_tuple(n):
+    return (1, "abc", u"\u00fc", 1.1)[n]