diff options
| -rw-r--r-- | Lib/test/test_capi/test_unicode.py | 6 | ||||
| -rw-r--r-- | Objects/unicodeobject.c | 23 |
2 files changed, 17 insertions, 12 deletions
diff --git a/Lib/test/test_capi/test_unicode.py b/Lib/test/test_capi/test_unicode.py index 9ef476a..e6f8542 100644 --- a/Lib/test/test_capi/test_unicode.py +++ b/Lib/test/test_capi/test_unicode.py @@ -1736,7 +1736,7 @@ class PyUnicodeWriterTest(unittest.TestCase): writer.write_char('=') # test PyUnicodeWriter_WriteSubstring() - writer.write_substring("[long]", 1, 5); + writer.write_substring("[long]", 1, 5) # test PyUnicodeWriter_WriteStr() writer.write_str(" value ") @@ -1862,6 +1862,10 @@ class PyUnicodeWriterTest(unittest.TestCase): with self.assertRaises(ValueError): writer.write_ucs4("text", -1) + def test_substring_empty(self): + writer = self.create_writer(0) + writer.write_substring("abc", 1, 1) + self.assertEqual(writer.finish(), '') @unittest.skipIf(ctypes is None, 'need ctypes') diff --git a/Objects/unicodeobject.c b/Objects/unicodeobject.c index 408d74f..6196a8e 100644 --- a/Objects/unicodeobject.c +++ b/Objects/unicodeobject.c @@ -13637,27 +13637,28 @@ int _PyUnicodeWriter_WriteSubstring(_PyUnicodeWriter *writer, PyObject *str, Py_ssize_t start, Py_ssize_t end) { - Py_UCS4 maxchar; - Py_ssize_t len; - assert(0 <= start); assert(end <= PyUnicode_GET_LENGTH(str)); assert(start <= end); - if (end == 0) - return 0; - if (start == 0 && end == PyUnicode_GET_LENGTH(str)) return _PyUnicodeWriter_WriteStr(writer, str); - if (PyUnicode_MAX_CHAR_VALUE(str) > writer->maxchar) + Py_ssize_t len = end - start; + if (len == 0) { + return 0; + } + + Py_UCS4 maxchar; + if (PyUnicode_MAX_CHAR_VALUE(str) > writer->maxchar) { maxchar = _PyUnicode_FindMaxChar(str, start, end); - else + } + else { maxchar = writer->maxchar; - len = end - start; - - if (_PyUnicodeWriter_Prepare(writer, len, maxchar) < 0) + } + if (_PyUnicodeWriter_Prepare(writer, len, maxchar) < 0) { return -1; + } _PyUnicode_FastCopyCharacters(writer->buffer, writer->pos, str, start, len); |