bpo-45467: Fix IncrementalDecoder and StreamReader in the "raw-unicode-escape" codec (GH-28944)

They support now splitting escape sequences between input chunks.

Add the third parameter "final" in codecs.raw_unicode_escape_decode().
It is True by default to match the former behavior.

2 files changed, 39 insertions, 5 deletions

diff --git a/Lib/encodings/raw_unicode_escape.py b/Lib/encodings/raw_unicode_escape.py
index 2b919b4..46c8e07 100644
--- a/Lib/encodings/raw_unicode_escape.py
+++ b/Lib/encodings/raw_unicode_escape.py
@@ -21,15 +21,16 @@ class IncrementalEncoder(codecs.IncrementalEncoder):
     def encode(self, input, final=False):
         return codecs.raw_unicode_escape_encode(input, self.errors)[0]
 
-class IncrementalDecoder(codecs.IncrementalDecoder):
-    def decode(self, input, final=False):
-        return codecs.raw_unicode_escape_decode(input, self.errors)[0]
+class IncrementalDecoder(codecs.BufferedIncrementalDecoder):
+    def _buffer_decode(self, input, errors, final):
+        return codecs.raw_unicode_escape_decode(input, errors, final)
 
 class StreamWriter(Codec,codecs.StreamWriter):
     pass
 
 class StreamReader(Codec,codecs.StreamReader):
-    pass
+    def decode(self, input, errors='strict'):
+        return codecs.raw_unicode_escape_decode(input, errors, False)
 
 ### encodings module API
 
diff --git a/Lib/test/test_codecs.py b/Lib/test/test_codecs.py
index 288a300..506b51c 100644
--- a/Lib/test/test_codecs.py
+++ b/Lib/test/test_codecs.py
@@ -2483,7 +2483,11 @@ class UnicodeEscapeTest(ReadTest, unittest.TestCase):
             ]
         )
 
-class RawUnicodeEscapeTest(unittest.TestCase):
+class RawUnicodeEscapeTest(ReadTest, unittest.TestCase):
+    encoding = "raw-unicode-escape"
+
+    test_lone_surrogates = None
+
     def test_empty(self):
         self.assertEqual(codecs.raw_unicode_escape_encode(""), (b"", 0))
         self.assertEqual(codecs.raw_unicode_escape_decode(b""), ("", 0))
@@ -2532,6 +2536,35 @@ class RawUnicodeEscapeTest(unittest.TestCase):
         self.assertEqual(decode(br"\U00110000", "ignore"), ("", 10))
         self.assertEqual(decode(br"\U00110000", "replace"), ("\ufffd", 10))
 
+    def test_partial(self):
+        self.check_partial(
+            "\x00\t\n\r\\\xff\uffff\U00010000",
+            [
+                '\x00',
+                '\x00\t',
+                '\x00\t\n',
+                '\x00\t\n\r',
+                '\x00\t\n\r',
+                '\x00\t\n\r\\\xff',
+                '\x00\t\n\r\\\xff',
+                '\x00\t\n\r\\\xff',
+                '\x00\t\n\r\\\xff',
+                '\x00\t\n\r\\\xff',
+                '\x00\t\n\r\\\xff',
+                '\x00\t\n\r\\\xff\uffff',
+                '\x00\t\n\r\\\xff\uffff',
+                '\x00\t\n\r\\\xff\uffff',
+                '\x00\t\n\r\\\xff\uffff',
+                '\x00\t\n\r\\\xff\uffff',
+                '\x00\t\n\r\\\xff\uffff',
+                '\x00\t\n\r\\\xff\uffff',
+                '\x00\t\n\r\\\xff\uffff',
+                '\x00\t\n\r\\\xff\uffff',
+                '\x00\t\n\r\\\xff\uffff',
+                '\x00\t\n\r\\\xff\uffff\U00010000',
+            ]
+        )
+
 
 class EscapeEncodeTest(unittest.TestCase):