Mercurial > hg
diff contrib/hgfixes/fix_bytesmod.py @ 11749:e627fef94604
hgfixes: added a fixer that makes bytes to be formatted correctly
This patch implement a fixer that replaces all calls to the '%' when bytes
arguments are used to a call to bytesformatter(), a function that knows how to
format byte strings. As one can't be sure if a formatting call is done when
only variables are used in a '%' call, these calls are also translated. The
bytesformatter, in runtime, makes sure to return the "raw" % operation if
that's what was intended.
author | Renato Cunha <renatoc@gmail.com> |
---|---|
date | Tue, 03 Aug 2010 13:59:14 -0300 |
parents | |
children | 681f7b9213a4 |
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--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/contrib/hgfixes/fix_bytesmod.py Tue Aug 03 13:59:14 2010 -0300 @@ -0,0 +1,63 @@ +"""Fixer that changes bytes % whatever to a function that actually formats +it.""" + +from lib2to3 import fixer_base +from lib2to3.fixer_util import is_tuple, Call, Comma, Name, touch_import + +# XXX: Implementing a blacklist in 2to3 turned out to be more troublesome than +# blacklisting some modules inside the fixers. So, this is what I came with. + +blacklist = ['mercurial/demandimport.py', + 'mercurial/py3kcompat.py', + 'mercurial/i18n.py', + ] + +def isnumberremainder(formatstr, data): + try: + if data.value.isdigit(): + return True + except AttributeError: + return False + +class FixBytesmod(fixer_base.BaseFix): + # XXX: There's one case (I suppose) I can't handle: when a remainder + # operation like foo % bar is performed, I can't really know what the + # contents of foo and bar are. I believe the best approach is to "correct" + # the to-be-converted code and let bytesformatter handle that case in + # runtime. + PATTERN = ''' + term< formatstr=STRING '%' data=STRING > | + term< formatstr=STRING '%' data=atom > | + term< formatstr=NAME '%' data=any > | + term< formatstr=any '%' data=any > + ''' + + def transform(self, node, results): + if self.filename in blacklist: + return + elif self.filename == 'mercurial/util.py': + touch_import('.', 'py3kcompat', node=node) + + formatstr = results['formatstr'].clone() + data = results['data'].clone() + formatstr.prefix = '' # remove spaces from start + + if isnumberremainder(formatstr, data): + return + + # We have two possibilities: + # 1- An identifier or name is passed, it is going to be a leaf, thus, we + # just need to copy its value as an argument to the formatter; + # 2- A tuple is explicitly passed. In this case, we're gonna explode it + # to pass to the formatter + # TODO: Check for normal strings. They don't need to be translated + + if is_tuple(data): + args = [formatstr, Comma().clone()] + \ + [c.clone() for c in data.children[:]] + else: + args = [formatstr, Comma().clone(), data] + + call = Call(Name('bytesformatter', prefix = ' '), args) + return call +