Fixed critical bug that could cause single bytes not to be returned in reads that should read all

Author: Byron

stream.py

@@ -249,9 +249,7 @@ def read(self, size=-1):
 
 		# get the actual window end to be sure we don't use it for computations
 		self._cwe = self._cws + len(indata)
-		
 		dcompdat = self._zip.decompress(indata, size)
-		
 		# update the amount of compressed bytes read
 		# We feed possibly overlapping chunks, which is why the unconsumed tail
 		# has to be taken into consideration, as well as the unused data
@@ -269,7 +267,7 @@ def read(self, size=-1):
 		# Note: dcompdat can be empty even though we still appear to have bytes
 		# to read, if we are called by compressed_bytes_read - it manipulates
 		# us to empty the stream
-		if dcompdat and len(dcompdat) < size and self._br < self._s:
+		if dcompdat and (len(dcompdat) - len(dat)) < size and self._br < self._s:
 			dcompdat += self.read(size-len(dcompdat))
 		# END handle special case
 		return dcompdat

test/fixtures/objects/7b/b839852ed5e3a069966281bb08d50012fb309b

@@ -4,12 +4,14 @@
 		DummyStream,
 		Sha1Writer, 
 		make_bytes, 
-		make_object
+		make_object,
+		fixture_path
 	)
 
 from gitdb import *
 from gitdb.util import (
-	NULL_HEX_SHA
+	NULL_HEX_SHA,
+	hex_to_bin
 	)
 
 from gitdb.util import zlib
@@ -135,4 +137,11 @@ def test_compressed_writer(self):
 			os.remove(path)
 		# END for each os
 
-
+	def test_decompress_reader_special_case(self):
+		odb = LooseObjectDB(fixture_path('objects'))
+		ostream = odb.stream(hex_to_bin('7bb839852ed5e3a069966281bb08d50012fb309b'))
+		
+		# if there is a bug, we will be missing one byte exactly !
+		data = ostream.read()
+		assert len(data) == ostream.size
+		

test/test_stream.py

@@ -56,6 +56,7 @@ def unpack_from(fmt, data, offset=0):
 mkdir = os.mkdir
 chmod = os.chmod
 isdir = os.path.isdir
+isfile = os.path.isfile
 rename = os.rename
 dirname = os.path.dirname
 basename = os.path.basename
@@ -288,7 +289,7 @@ def _end_writing(self, successful=True):
 		if self._write and successful:
 			# on windows, rename does not silently overwrite the existing one
 			if sys.platform == "win32":
-				if os.path.isfile(self._filepath):
+				if isfile(self._filepath):
 					os.remove(self._filepath)
 				# END remove if exists
 			# END win32 special handling