Add tests for BufferedStream.

Author: gsnedders

html5lib/tests/test_stream.py

@@ -3,8 +3,71 @@
 from . import support  # flake8: noqa
 import unittest
 import codecs
-
-from html5lib.inputstream import HTMLInputStream, HTMLUnicodeInputStream, HTMLBinaryInputStream
+from io import BytesIO
+
+from html5lib.inputstream import (BufferedStream, HTMLInputStream,
+                                  HTMLUnicodeInputStream, HTMLBinaryInputStream)
+
+class BufferedStreamTest(unittest.TestCase):
+    def test_basic(self):
+        s = b"abc"
+        fp = BufferedStream(BytesIO(s))
+        read = fp.read(10)
+        assert read == s
+
+    def test_read_length(self):
+        fp = BufferedStream(BytesIO(b"abcdef"))
+        read1 = fp.read(1)
+        assert read1 == b"a"
+        read2 = fp.read(2)
+        assert read2 == b"bc"
+        read3 = fp.read(3)
+        assert read3 == b"def"
+        read4 = fp.read(4)
+        assert read4 == b""
+
+    def test_tell(self):
+        fp = BufferedStream(BytesIO(b"abcdef"))
+        read1 = fp.read(1)
+        assert fp.tell() == 1
+        read2 = fp.read(2)
+        assert fp.tell() == 3
+        read3 = fp.read(3)
+        assert fp.tell() == 6
+        read4 = fp.read(4)
+        assert fp.tell() == 6
+
+    def test_seek(self):
+        fp = BufferedStream(BytesIO(b"abcdef"))
+        read1 = fp.read(1)
+        assert read1 == b"a"
+        fp.seek(0)
+        read2 = fp.read(1)
+        assert read2 == b"a"
+        read3 = fp.read(2)
+        assert read3 == b"bc"
+        fp.seek(2)
+        read4 = fp.read(2)
+        assert read4 == b"cd"
+        fp.seek(4)
+        read5 = fp.read(2)
+        assert read5 == b"ef"
+
+    def test_seek_tell(self):
+        fp = BufferedStream(BytesIO(b"abcdef"))
+        read1 = fp.read(1)
+        assert fp.tell() == 1
+        fp.seek(0)
+        read2 = fp.read(1)
+        assert fp.tell() == 1
+        read3 = fp.read(2)
+        assert fp.tell() == 3
+        fp.seek(2)
+        read4 = fp.read(2)
+        assert fp.tell() == 4
+        fp.seek(4)
+        read5 = fp.read(2)
+        assert fp.tell() == 6
 
 
 class HTMLUnicodeInputStreamShortChunk(HTMLUnicodeInputStream):