gh-81322: support multiple separators in StreamReader.readuntil (#16429)

1 files changed, 46 insertions, 0 deletions

diff --git a/Lib/test/test_asyncio/test_streams.py b/Lib/test/test_asyncio/test_streams.py
index 2cf48538d5d..792e88761ac 100644
--- a/Lib/test/test_asyncio/test_streams.py
+++ b/Lib/test/test_asyncio/test_streams.py
@@ -383,6 +383,10 @@ class StreamTests(test_utils.TestCase):
         stream = asyncio.StreamReader(loop=self.loop)
         with self.assertRaisesRegex(ValueError, 'Separator should be'):
             self.loop.run_until_complete(stream.readuntil(separator=b''))
+        with self.assertRaisesRegex(ValueError, 'Separator should be'):
+            self.loop.run_until_complete(stream.readuntil(separator=[b'']))
+        with self.assertRaisesRegex(ValueError, 'Separator should contain'):
+            self.loop.run_until_complete(stream.readuntil(separator=[]))
 
     def test_readuntil_multi_chunks(self):
         stream = asyncio.StreamReader(loop=self.loop)
@@ -466,6 +470,48 @@ class StreamTests(test_utils.TestCase):
 
         self.assertEqual(b'some dataAAA', stream._buffer)
 
+    def test_readuntil_multi_separator(self):
+        stream = asyncio.StreamReader(loop=self.loop)
+
+        # Simple case
+        stream.feed_data(b'line 1\nline 2\r')
+        data = self.loop.run_until_complete(stream.readuntil([b'\r', b'\n']))
+        self.assertEqual(b'line 1\n', data)
+        data = self.loop.run_until_complete(stream.readuntil([b'\r', b'\n']))
+        self.assertEqual(b'line 2\r', data)
+        self.assertEqual(b'', stream._buffer)
+
+        # First end position matches, even if that's a longer match
+        stream.feed_data(b'ABCDEFG')
+        data = self.loop.run_until_complete(stream.readuntil([b'DEF', b'BCDE']))
+        self.assertEqual(b'ABCDE', data)
+        self.assertEqual(b'FG', stream._buffer)
+
+    def test_readuntil_multi_separator_limit(self):
+        stream = asyncio.StreamReader(loop=self.loop, limit=3)
+        stream.feed_data(b'some dataA')
+
+        with self.assertRaisesRegex(asyncio.LimitOverrunError,
+                                    'is found') as cm:
+            self.loop.run_until_complete(stream.readuntil([b'A', b'ome dataA']))
+
+        self.assertEqual(b'some dataA', stream._buffer)
+
+    def test_readuntil_multi_separator_negative_offset(self):
+        # If the buffer is big enough for the smallest separator (but does
+        # not contain it) but too small for the largest, `offset` must not
+        # become negative.
+        stream = asyncio.StreamReader(loop=self.loop)
+        stream.feed_data(b'data')
+
+        readuntil_task = self.loop.create_task(stream.readuntil([b'A', b'long sep']))
+        self.loop.call_soon(stream.feed_data, b'Z')
+        self.loop.call_soon(stream.feed_data, b'Aaaa')
+
+        data = self.loop.run_until_complete(readuntil_task)
+        self.assertEqual(b'dataZA', data)
+        self.assertEqual(b'aaa', stream._buffer)
+
     def test_readexactly_zero_or_less(self):
         # Read exact number of bytes (zero or less).
         stream = asyncio.StreamReader(loop=self.loop)