view tests/test-symlink-placeholder.t @ 24710:909ee6b2a024

lazymanifest: prevent leak when updating an entry more than once

__setitem__ on the lazymanifest C type wasn't checking to see if a
line had previously been malloced before replacing it, leading to
leaks if files got updated multiple times in the course of a task.

I was able to reproduce the leak with this change to test-manifest.py:

diff --git a/tests/test-manifest.py b/tests/test-manifest.py
--- a/tests/test-manifest.py
+++ b/tests/test-manifest.py
@@ -456,6 +456,16 @@ class basemanifesttests(object):
                 ['a/b/c/bar.txt', 'a/b/c/foo.txt', 'a/b/d/ten.txt'],
                 m2.keys())

+    def testManifestSetItem(self):
+        m = self.parsemanifest('')
+        for x in range(3):
+            m['file%d' % x] = BIN_HASH_1
+        for x in range(3):
+            m['file%d' % x] = BIN_HASH_2
+        import time
+        time.sleep(4)
+
+

along with the commands:

 $ make local
 $ PYTHONPATH=. SILENT_BE_NOISY=1 python tests/test-manifest.py testmanifestdict.testManifestSetItem &
 $ sleep 4
 $ leaks $(jobs -p | tee /dev/stderr | awk '{print $3}')
 $ wait

in an interactive shell on OS X. As far as I can tell, it had to be an
interactive shell so that I could get the pid of the test run using
the jobs builtin. Prior to this change, I was leaking several strings,
and after this change leaks reports no leaks.

I thought there was a bug filed for this in bugzilla, but I can't find
it either in bugzilla or by searching my email.

#require symlink

Create extension that can disable symlink support:

  $ cat > nolink.py <<EOF
  > from mercurial import extensions, util
  > def setflags(orig, f, l, x):
  >     pass
  > def checklink(orig, path):
  >     return False
  > def extsetup(ui):
  >     extensions.wrapfunction(util, 'setflags', setflags)
  >     extensions.wrapfunction(util, 'checklink', checklink)
  > EOF

  $ hg init unix-repo
  $ cd unix-repo
  $ echo foo > a
  $ ln -s a b
  $ hg ci -Am0
  adding a
  adding b
  $ cd ..

Simulate a checkout shared on NFS/Samba:

  $ hg clone -q unix-repo shared
  $ cd shared
  $ rm b
  $ echo foo > b
  $ hg --config extensions.n=$TESTTMP/nolink.py status --debug
  ignoring suspect symlink placeholder "b"

Make a clone using placeholders:

  $ hg --config extensions.n=$TESTTMP/nolink.py clone . ../win-repo
  updating to branch default
  2 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ cd ../win-repo
  $ cat b
  a (no-eol)
  $ hg --config extensions.n=$TESTTMP/nolink.py st --debug

Empty placeholder:

  $ rm b
  $ touch b
  $ hg --config extensions.n=$TESTTMP/nolink.py st --debug
  ignoring suspect symlink placeholder "b"

Write binary data to the placeholder:

  >>> open('b', 'w').write('this is a binary\0')
  $ hg --config extensions.n=$TESTTMP/nolink.py st --debug
  ignoring suspect symlink placeholder "b"

Write a long string to the placeholder:

  >>> open('b', 'w').write('this' * 1000)
  $ hg --config extensions.n=$TESTTMP/nolink.py st --debug
  ignoring suspect symlink placeholder "b"

Commit shouldn't succeed:

  $ hg --config extensions.n=$TESTTMP/nolink.py ci -m1
  nothing changed
  [1]

Write a valid string to the placeholder:

  >>> open('b', 'w').write('this')
  $ hg --config extensions.n=$TESTTMP/nolink.py st --debug
  M b
  $ hg --config extensions.n=$TESTTMP/nolink.py ci -m1
  $ hg manifest tip --verbose
  644   a
  644 @ b

  $ cd ..