[pypy-commit] pypy default: Fix underlying list of bytearrays being reused inappropriately

[waedt]

Author: Tyler Wade <wayedt at gmail.com>
Branch: 
Changeset: r72431:2eef95188f80
Date: 2014-07-13 05:50 -0500
http://bitbucket.org/pypy/pypy/changeset/2eef95188f80/

Log:	Fix underlying list of bytearrays being reused inappropriately

diff --git a/pypy/objspace/std/bytearrayobject.py b/pypy/objspace/std/bytearrayobject.py
--- a/pypy/objspace/std/bytearrayobject.py
+++ b/pypy/objspace/std/bytearrayobject.py
@@ -41,6 +41,8 @@
         return ''.join(self.data)
 
     def _new(self, value):
+        if value is self.data:
+            value = value[:]
         return W_BytearrayObject(value)
 
     def _new_from_buffer(self, buffer):
diff --git a/pypy/objspace/std/stringmethods.py b/pypy/objspace/std/stringmethods.py
--- a/pypy/objspace/std/stringmethods.py
+++ b/pypy/objspace/std/stringmethods.py
@@ -455,7 +455,7 @@
         d = width - len(value)
         if d > 0:
             fillchar = self._multi_chr(fillchar[0])
-            value += d * fillchar
+            value = value + fillchar * d
 
         return self._new(value)
 
diff --git a/pypy/objspace/std/test/test_bytearrayobject.py b/pypy/objspace/std/test/test_bytearrayobject.py
--- a/pypy/objspace/std/test/test_bytearrayobject.py
+++ b/pypy/objspace/std/test/test_bytearrayobject.py
@@ -223,6 +223,20 @@
         check(bytearray('abc').rstrip(memoryview('c')), 'ab')
         check(bytearray('aba').strip('a'), 'b')
 
+    def test_xjust_no_mutate(self):
+        # a previous regression
+        b = bytearray(b'')
+        assert b.ljust(1) == bytearray(b' ')
+        assert not len(b)
+
+        b2 = b.ljust(0)
+        b2 += b' '
+        assert not len(b)
+
+        b2 = b.rjust(0)
+        b2 += b' '
+        assert not len(b)
+
     def test_split(self):
         # methods that should return a sequence of bytearrays
         def check(result, expected):