Don't pollute the working directory with lextab and yacctab

[natezb]

Currently, whenever we use pycparser (either directly or indirectly via cffi), lextab.py and yacctab.py files are generated in the working directory. Instead, we should generate them in a temp directory.

Unfortunately, cffi doesn't currently support setting this directory, though pycparser does. As a hacky workaround, you can instantiate your own CParser which will use a temp directory, then set it as the global parser instance in pycparser.

See the pco driver in Instrumental for a working example of this.

[natezb]

My understanding now is that this is only happening for me b/c I'm using a local development version of pycparser. An ordinary release version installed via pip should not have this issue.

[superted6851]

Some strange behaviour when installing from pip (pip install nicelib) _build_tables.py does not run on setup. Hence every time nicelib is imported it creates the tables. Only python setup.py install creates the tables every time.

pip install NiceLib/ -v

Output:

Build the lexing/parsing tables creating build/bdist.macosx-10.9-x86_64/wheel/NiceLib-0.7.dev0.dist-info/WHEEL creating '/private/var/folders/5m/vlz3kp392gx3ztcx3mxxzmy00000gn/T/pip-wheel-goa862fg/NiceLib-0.7.dev0-py2.py3-none-any.whl' and adding 'build/bdist.macosx-10.9-x86_64/wheel' to it adding 'nicelib/__about__.py' adding 'nicelib/__init__.py' adding 'nicelib/build.py' adding 'nicelib/nicelib.py' adding 'nicelib/platform.py' adding 'nicelib/process.py' adding 'nicelib/util.py' adding 'nicelib/parser/__init__.py' adding 'nicelib/parser/_build_tables.py' adding 'nicelib/parser/cpp_generator.py' adding 'nicelib/parser/cpp_lexer.py' adding 'nicelib/parser/cpp_parser.py' adding 'NiceLib-0.7.dev0.dist-info/LICENSE' adding 'NiceLib-0.7.dev0.dist-info/METADATA' adding 'NiceLib-0.7.dev0.dist-info/WHEEL' adding 'NiceLib-0.7.dev0.dist-info/top_level.txt' adding 'NiceLib-0.7.dev0.dist-info/RECORD' removing build/bdist.macosx-10.9-x86_64/wheel done

If it is run a second time then the tables are generated, so the behavoir is quite strange.

Build the lexing/parsing tables creating build/bdist.macosx-10.9-x86_64/wheel/NiceLib-0.7.dev0.dist-info/WHEEL creating '/private/var/folders/5m/vlz3kp392gx3ztcx3mxxzmy00000gn/T/pip-wheel-goa862fg/NiceLib-0.7.dev0-py2.py3-none-any.whl' and adding 'build/bdist.macosx-10.9-x86_64/wheel' to it adding 'nicelib/__about__.py' adding 'nicelib/__init__.py' adding 'nicelib/build.py' adding 'nicelib/nicelib.py' adding 'nicelib/platform.py' adding 'nicelib/process.py' adding 'nicelib/util.py' adding 'nicelib/parser/__init__.py' adding 'nicelib/parser/_build_tables.py' adding 'nicelib/parser/cpp_generator.py' adding 'nicelib/parser/cpp_lexer.py' adding 'nicelib/parser/cpp_parser.py' adding 'nicelib/parser/lextab.py' adding 'nicelib/parser/yacctab.py' adding 'NiceLib-0.7.dev0.dist-info/LICENSE' adding 'NiceLib-0.7.dev0.dist-info/METADATA' adding 'NiceLib-0.7.dev0.dist-info/WHEEL' adding 'NiceLib-0.7.dev0.dist-info/top_level.txt' adding 'NiceLib-0.7.dev0.dist-info/RECORD' removing build/bdist.macosx-10.9-x86_64/wheel done

[natezb]

I am able to reproduce this, I'l look into it.

[superted6851]

Considering yacctab.py and lextab.py are generated by pycparser on installation can we not just link to these files? Seems just changing lines 16 and 17 of cpp_parser.py to

class CPPParser(CParser):
   def __init__(self, **kwds):  
        kwds['lexer'] = CPPLexer  
        kwds['lextab'] = 'pycparser.lextab'  
        kwds['yacctab'] = 'pycparser.yacctab'  
       CParser.__init__(self, **kwds)

works.

[Tillsten]

This still happens for me.