Mercurial > hg
view tests/test-casefolding.t @ 14007:d764463b433e
atomictempfile: avoid infinite recursion in __del__().
The problem is that a programmer using atomictempfile directly can
make an innocent everyday mistake -- not enough args to the
constructor -- which escalates badly. You would expect a simple
TypeError crash in that case, but you actually get an infinite
recursion that is surprisingly difficult to kill: it happens between
__del__() and __getattr__(), and Python does not handle infinite
recursion from __del__() well.
The fix is to not implement __getattr__(), but instead assign instance
attributes for the methods we wish to delegate to the builtin file
type: write() and fileno(). I've audited mercurial.* and hgext.* and
found no users of atomictempfile using methods other than write() and
rename(). I audited third-party extensions and found one (snap)
passing an atomictempfile to util.fstat(), so I also threw in
fileno().
The last time I submitted a similar patch, Matt proposed that we make
atomictempfile a subclass of file instead of wrapping it. Rejected on
grounds of unnecessary complexity: for one thing, it would make the
Windows implementation of posixfile quite a bit more complex. It would
have to become a subclass of file rather than a simple function -- but
since it's written in C, this is non-obvious and non-trivial.
Furthermore, there's nothing wrong with wrapping objects and
delegating methods: it's a well-established pattern that works just
fine in many cases. Subclassing is not the answer to all of life's
problems.
author | Greg Ward <greg@gerg.ca> |
---|---|
date | Sun, 24 Apr 2011 19:25:10 -0400 |
parents | f1646efc54a6 |
children | b0a88bda3381 |
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$ "$TESTDIR/hghave" icasefs || exit 80 test file addition with bad case $ hg init repo1 $ cd repo1 $ echo a > a $ hg add A adding a $ hg st A a $ hg ci -m adda $ hg manifest a $ cd .. test case collision on rename (issue750) $ hg init repo2 $ cd repo2 $ echo a > a $ hg --debug ci -Am adda adding a a committed changeset 0:07f4944404050f47db2e5c5071e0e84e7a27bba9 $ hg mv a A A: not overwriting - file exists 'a' used to be removed under windows $ test -f a || echo 'a is missing' $ hg st $ cd .. test case collision between revisions (issue912) $ hg init repo3 $ cd repo3 $ echo a > a $ hg ci -Am adda adding a $ hg rm a $ hg ci -Am removea $ echo A > A on linux hfs keeps the old case stored, force it $ mv a aa $ mv aa A $ hg ci -Am addA adding A used to fail under case insensitive fs $ hg up -C 0 1 files updated, 0 files merged, 1 files removed, 0 files unresolved $ hg up -C 1 files updated, 0 files merged, 1 files removed, 0 files unresolved $ cd ..