def _key()

in build/fbcode_builder/getdeps/envfuncs.py [0:0]

• 9 lines of code
• 12 McCabe index (conditional complexity)

    def _key(self, key):
        # The `str` cast may not appear to be needed, but without it we run
        # into issues when passing the environment to subprocess.  The main
        # issue is that in python2 `os.environ` (which is the initial source
        # of data for the environment) uses byte based strings, but this
        # project uses `unicode_literals`.  `subprocess` will raise an error
        # if the environment that it is passed has a mixture of byte and
        # unicode strings.
        # It is simplest to force everthing to be `str` for the sake of
        # consistency.
        key = str(key)
        if sys.platform.startswith("win"):
            # Windows env var names are case insensitive but case preserving.
            # An implementation of PAR files on windows gets confused if
            # the env block contains keys with conflicting case, so make a
            # pass over the contents to remove any.
            # While this O(n) scan is technically expensive and gross, it
            # is practically not a problem because the volume of calls is
            # relatively low and the cost of manipulating the env is dwarfed
            # by the cost of spawning a process on windows.  In addition,
            # since the processes that we run are expensive anyway, this
            # overhead is not the worst thing to worry about.
            for k in list(self._dict.keys()):
                if str(k).lower() == key.lower():
                    return k
        elif key in self._dict:
            return key
        return None