Mercurial > hg
view tests/test-hgwebdir-paths.py @ 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 | a767998f0a78 |
children | dbdb777502dc |
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import os from mercurial import hg, ui from mercurial.hgweb.hgwebdir_mod import hgwebdir os.mkdir('webdir') os.chdir('webdir') webdir = os.path.realpath('.') u = ui.ui() hg.repository(u, 'a', create=1) hg.repository(u, 'b', create=1) os.chdir('b') hg.repository(u, 'd', create=1) os.chdir('..') hg.repository(u, 'c', create=1) os.chdir('..') paths = {'t/a/': '%s/a' % webdir, 'b': '%s/b' % webdir, 'coll': '%s/*' % webdir, 'rcoll': '%s/**' % webdir} config = os.path.join(webdir, 'hgwebdir.conf') configfile = open(config, 'w') configfile.write('[paths]\n') for k, v in paths.items(): configfile.write('%s = %s\n' % (k, v)) configfile.close() confwd = hgwebdir(config) dictwd = hgwebdir(paths) assert len(confwd.repos) == len(dictwd.repos), 'different numbers' assert len(confwd.repos) == 9, 'expected 9 repos, found %d' % len(confwd.repos) found = dict(confwd.repos) for key, path in dictwd.repos: assert key in found, 'repository %s was not found' % key assert found[key] == path, 'different paths for repo %s' % key