Split up flake8/run.py

I've preserved the API for users expecting their hooks and other things to
work.

That said, I'm working on #51 now as well.

flake8/main.py

@@ -0,0 +1,169 @@
+import os
+import sys
+import pep8
+import flakey
+import select
+import optparse
+from flake8 import mccabe
+from flake8 import __version__
+from flake8.util import _initpep8, skip_file
+
+pep8style = None
+
+
+def get_parser():
+    """Create a custom OptionParser"""
+
+    def version(option, opt, value, parser):
+        parser.print_usage()
+        parser.print_version()
+        sys.exit(0)
+
+    # Create our own parser
+    parser = optparse.OptionParser('%prog [options] [file.py|directory]',
+                                   version=version)
+    parser.version = '{0} (pep8: {1}, flakey: {2})'.format(
+        __version__, pep8.__version__, flakey.__version__)
+    parser.remove_option('--version')
+    # don't overlap with pep8's verbose option
+    parser.add_option('--builtins', default='', dest='builtins',
+                      help="append builtin functions to flakey's "
+                           "_MAGIC_BUILTINS")
+    parser.add_option('--ignore', default='',
+                      help='skip errors and warnings (e.g. E4,W)')
+    parser.add_option('--exit-zero', action='store_true', default=False,
+                      help='Exit with status 0 even if there are errors')
+    parser.add_option('--max-complexity', default=-1, action='store',
+                      type='int', help='McCabe complexity threshold')
+    parser.add_option('-V', '--version', action='callback',
+                      callback=version,
+                      help='Print the version info for flake8')
+    return parser
+
+
+def main():
+    global pep8style
+
+    # parse out our flags so pep8 doesn't get confused
+    parser = get_parser()
+    opts, sys.argv = parser.parse_args()
+
+    # make sure pep8 gets the information it expects
+    sys.argv.insert(0, 'pep8')
+
+    pep8style = pep8.StyleGuide(parse_argv=True, config_file=True)
+    options = pep8style.options
+    complexity = opts.max_complexity
+    builtins = set(opts.builtins.split(','))
+    warnings = 0
+    stdin = None
+
+    if builtins:
+        orig_builtins = set(flakey.checker._MAGIC_GLOBALS)
+        flakey.checker._MAGIC_GLOBALS = orig_builtins | builtins
+
+    if pep8style.paths and options.filename is not None:
+        for path in _get_python_files(pep8style.paths):
+            if path == '-':
+                if stdin is None:
+                    stdin = read_stdin()
+                warnings += check_code(stdin, opts.ignore, complexity)
+            else:
+                warnings += check_file(path, opts.ignore, complexity)
+    else:
+        stdin = read_stdin()
+        warnings += check_code(stdin, opts.ignore, complexity)
+
+    if opts.exit_zero:
+        raise SystemExit(0)
+
+    raise SystemExit(warnings)
+
+
+def check_file(path, ignore=(), complexity=-1):
+    if pep8style.excluded(path):
+        return 0
+    warning = flakey.checkPath(path)
+    warnings = flakey.print_messages(warning, ignore=ignore)
+    warnings += pep8style.input_file(path)
+    if complexity > -1:
+        warnings += mccabe.get_module_complexity(path, complexity)
+    return warnings
+
+
+def check_code(code, ignore=(), complexity=-1):
+    warning = flakey.check(code, 'stdin')
+    warnings = flakey.print_messages(warning, ignore=ignore)
+    warnings += pep8style.input_file(None, lines=code.split('\n'))
+    if complexity > -1:
+        warnings += mccabe.get_code_complexity(code, complexity)
+    return warnings
+
+
+def read_stdin():
+    # wait for 1 second on the stdin fd
+    reads, __, __ = select.select([sys.stdin], [], [], 1.)
+    if reads == []:
+        print('input not specified')
+        raise SystemExit(1)
+
+    return sys.stdin.read()
+
+
+try:
+    from setuptools import Command
+except ImportError:
+    Flake8Command = None
+else:
+    class Flake8Command(Command):
+        description = "Run flake8 on modules registered in setuptools"
+        user_options = []
+
+        def initialize_options(self):
+            pass
+
+        def finalize_options(self):
+            pass
+
+        def distribution_files(self):
+            if self.distribution.packages:
+                for package in self.distribution.packages:
+                    yield package.replace(".", os.path.sep)
+
+            if self.distribution.py_modules:
+                for filename in self.distribution.py_modules:
+                    yield "%s.py" % filename
+
+        def run(self):
+            _initpep8()
+
+            # _get_python_files can produce the same file several
+            # times, if one of its paths is a parent of another. Keep
+            # a set of checked files to de-duplicate.
+            checked = set()
+
+            warnings = 0
+            for path in _get_python_files(self.distribution_files()):
+                if path not in checked:
+                    warnings += check_file(path)
+                checked.add(path)
+
+            raise SystemExit(warnings > 0)
+
+
+def _get_python_files(paths):
+    for path in paths:
+        if os.path.isdir(path):
+            for dirpath, dirnames, filenames in os.walk(path):
+                if pep8style.excluded(dirpath):
+                    continue
+                for filename in filenames:
+                    if not filename.endswith('.py'):
+                        continue
+                    fullpath = os.path.join(dirpath, filename)
+                    if not skip_file(fullpath) or pep8style.excluded(fullpath):
+                        yield fullpath
+
+        else:
+            if not skip_file(path) or pep8style.excluded(path):
+                yield path