Avoid allocating bytes slice in encoding pre-parse

gsnedders · gsnedders · commit a2b4cf47a19c · 2020-06-09T02:30:22.000+01:00
diff --git a/html5lib/_inputstream.py b/html5lib/_inputstream.py
@@ -658,9 +658,7 @@ def matchBytes(self, bytes):
         """Look for a sequence of bytes at the start of a string. If the bytes
         are found return True and advance the position to the byte after the
         match. Otherwise return False and leave the position alone"""
-        p = self.position
-        data = self[p:p + len(bytes)]
-        rv = data.startswith(bytes)
+        rv = self.startswith(bytes, self.position)
         if rv:
             self.position += len(bytes)
         return rv

Original file line number	Diff line number	Diff line change
`@@ -658,9 +658,7 @@ def matchBytes(self, bytes):`
`658`	`658`	`"""Look for a sequence of bytes at the start of a string. If the bytes`
`659`	`659`	`are found return True and advance the position to the byte after the`
`660`	`660`	`match. Otherwise return False and leave the position alone"""`
`661`		`- p = self.position`
`662`		`- data = self[p:p + len(bytes)]`
`663`		`- rv = data.startswith(bytes)`
	`661`	`+ rv = self.startswith(bytes, self.position)`
`664`	`662`	`if rv:`
`665`	`663`	`self.position += len(bytes)`
`666`	`664`	`return rv`