Issue #12646: Add an 'eof' attribute to zlib.Decompress.

This will make it easier to detect truncated input streams.

Also, make zlib's error messages more consistent.

1 files changed, 20 insertions, 0 deletions

diff --git a/Lib/test/test_zlib.py b/Lib/test/test_zlib.py
index 68dd3ea..dddde47 100644
--- a/Lib/test/test_zlib.py
+++ b/Lib/test/test_zlib.py
@@ -447,6 +447,26 @@ class CompressObjectTestCase(BaseCompressTestCase, unittest.TestCase):
         y += dco.flush()
         self.assertEqual(y, b'foo')
 
+    def test_decompress_eof(self):
+        x = b'x\x9cK\xcb\xcf\x07\x00\x02\x82\x01E'  # 'foo'
+        dco = zlib.decompressobj()
+        self.assertFalse(dco.eof)
+        dco.decompress(x[:-5])
+        self.assertFalse(dco.eof)
+        dco.decompress(x[-5:])
+        self.assertTrue(dco.eof)
+        dco.flush()
+        self.assertTrue(dco.eof)
+
+    def test_decompress_eof_incomplete_stream(self):
+        x = b'x\x9cK\xcb\xcf\x07\x00\x02\x82\x01E'  # 'foo'
+        dco = zlib.decompressobj()
+        self.assertFalse(dco.eof)
+        dco.decompress(x[:-5])
+        self.assertFalse(dco.eof)
+        dco.flush()
+        self.assertFalse(dco.eof)
+
     if hasattr(zlib.compressobj(), "copy"):
         def test_compresscopy(self):
             # Test copying a compression object