#!/usr/bin/python # pep8.py - Check Python source code formatting, according to PEP 8 # Copyright (C) 2006 Johann C. Rocholl # # Permission is hereby granted, free of charge, to any person # obtaining a copy of this software and associated documentation files # (the "Software"), to deal in the Software without restriction, # including without limitation the rights to use, copy, modify, merge, # publish, distribute, sublicense, and/or sell copies of the Software, # and to permit persons to whom the Software is furnished to do so, # subject to the following conditions: # # The above copyright notice and this permission notice shall be # included in all copies or substantial portions of the Software. # # THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, # EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF # MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND # NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS # BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN # ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN # CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE # SOFTWARE. """ Check Python source code formatting, according to PEP 8: http://www.python.org/dev/peps/pep-0008/ For usage and a list of options, try this: $ python pep8.py -h This program and its regression test suite live here: http://github.com/jcrocholl/pep8 Groups of errors and warnings: E errors W warnings 100 indentation 200 whitespace 300 blank lines 400 imports 500 line length 600 deprecation 700 statements You can add checks to this program by writing plugins. Each plugin is a simple function that is called for each line of source code, either physical or logical. Physical line: - Raw line of text from the input file. Logical line: - Multi-line statements converted to a single line. - Stripped left and right. - Contents of strings replaced with 'xxx' of same length. - Comments removed. The check function requests physical or logical lines by the name of the first argument: def maximum_line_length(physical_line) def extraneous_whitespace(logical_line) def blank_lines(logical_line, blank_lines, indent_level, line_number) The last example above demonstrates how check plugins can request additional information with extra arguments. All attributes of the Checker object are available. Some examples: lines: a list of the raw lines from the input file tokens: the tokens that contribute to this logical line line_number: line number in the input file blank_lines: blank lines before this one indent_char: first indentation character in this file (' ' or '\t') indent_level: indentation (with tabs expanded to multiples of 8) previous_indent_level: indentation on previous line previous_logical: previous logical line The docstring of each check function shall be the relevant part of text from PEP 8. It is printed if the user enables --show-pep8. Several docstrings contain examples directly from the PEP 8 document. Okay: spam(ham[1], {eggs: 2}) E201: spam( ham[1], {eggs: 2}) These examples are verified automatically when pep8.py is run with the --doctest option. You can add examples for your own check functions. The format is simple: "Okay" or error/warning code followed by colon and space, the rest of the line is example source code. If you put 'r' before the docstring, you can use \n for newline, \t for tab and \s for space. """ __version__ = '0.5.1dev' import os import sys import re import time import inspect import keyword import tokenize from optparse import OptionParser from fnmatch import fnmatch try: frozenset except NameError: from sets import ImmutableSet as frozenset DEFAULT_EXCLUDE = '.svn,CVS,.bzr,.hg,.git' DEFAULT_IGNORE = 'E24' MAX_LINE_LENGTH = 79 INDENT_REGEX = re.compile(r'([ \t]*)') RAISE_COMMA_REGEX = re.compile(r'raise\s+\w+\s*(,)') SELFTEST_REGEX = re.compile(r'(Okay|[EW]\d{3}):\s(.*)') ERRORCODE_REGEX = re.compile(r'[EW]\d{3}') DOCSTRING_REGEX = re.compile(r'u?r?["\']') WHITESPACE_AROUND_OPERATOR_REGEX = \ re.compile('([^\w\s]*)\s*(\t| )\s*([^\w\s]*)') EXTRANEOUS_WHITESPACE_REGEX = re.compile(r'[[({] | []}),;:]') WHITESPACE_AROUND_NAMED_PARAMETER_REGEX = \ re.compile(r'[()]|\s=[^=]|[^=!<>]=\s') WHITESPACE = ' \t' BINARY_OPERATORS = frozenset(['**=', '*=', '+=', '-=', '!=', '<>', '%=', '^=', '&=', '|=', '==', '/=', '//=', '<=', '>=', '<<=', '>>=', '%', '^', '&', '|', '=', '/', '//', '<', '>', '<<']) UNARY_OPERATORS = frozenset(['>>', '**', '*', '+', '-']) OPERATORS = BINARY_OPERATORS | UNARY_OPERATORS SKIP_TOKENS = frozenset([tokenize.COMMENT, tokenize.NL, tokenize.INDENT, tokenize.DEDENT, tokenize.NEWLINE]) E225NOT_KEYWORDS = (frozenset(keyword.kwlist + ['print']) - frozenset(['False', 'None', 'True'])) BENCHMARK_KEYS = ('directories', 'files', 'logical lines', 'physical lines') options = None args = None ############################################################################## # Plugins (check functions) for physical lines ############################################################################## def tabs_or_spaces(physical_line, indent_char): r""" Never mix tabs and spaces. The most popular way of indenting Python is with spaces only. The second-most popular way is with tabs only. Code indented with a mixture of tabs and spaces should be converted to using spaces exclusively. When invoking the Python command line interpreter with the -t option, it issues warnings about code that illegally mixes tabs and spaces. When using -tt these warnings become errors. These options are highly recommended! Okay: if a == 0:\n a = 1\n b = 1 E101: if a == 0:\n a = 1\n\tb = 1 """ indent = INDENT_REGEX.match(physical_line).group(1) for offset, char in enumerate(indent): if char != indent_char: return offset, "E101 indentation contains mixed spaces and tabs" def tabs_obsolete(physical_line): r""" For new projects, spaces-only are strongly recommended over tabs. Most editors have features that make this easy to do. Okay: if True:\n return W191: if True:\n\treturn """ indent = INDENT_REGEX.match(physical_line).group(1) if indent.count('\t'): return indent.index('\t'), "W191 indentation contains tabs" def trailing_whitespace(physical_line): r""" JCR: Trailing whitespace is superfluous. FBM: Except when it occurs as part of a blank line (i.e. the line is nothing but whitespace). According to Python docs[1] a line with only whitespace is considered a blank line, and is to be ignored. However, matching a blank line to its indentation level avoids mistakenly terminating a multi-line statement (e.g. class declaration) when pasting code into the standard Python interpreter. [1] http://docs.python.org/reference/lexical_analysis.html#blank-lines The warning returned varies on whether the line itself is blank, for easier filtering for those who want to indent their blank lines. Okay: spam(1) W291: spam(1)\s W293: class Foo(object):\n \n bang = 12 """ physical_line = physical_line.rstrip('\n') # chr(10), newline physical_line = physical_line.rstrip('\r') # chr(13), carriage return physical_line = physical_line.rstrip('\x0c') # chr(12), form feed, ^L stripped = physical_line.rstrip() if physical_line != stripped: if stripped: return len(stripped), "W291 trailing whitespace" else: return 0, "W293 blank line contains whitespace" def trailing_blank_lines(physical_line, lines, line_number): r""" JCR: Trailing blank lines are superfluous. Okay: spam(1) W391: spam(1)\n """ if physical_line.strip() == '' and line_number == len(lines): return 0, "W391 blank line at end of file" def missing_newline(physical_line): """ JCR: The last line should have a newline. """ if physical_line.rstrip() == physical_line: return len(physical_line), "W292 no newline at end of file" def maximum_line_length(physical_line): """ Limit all lines to a maximum of 79 characters. There are still many devices around that are limited to 80 character lines; plus, limiting windows to 80 characters makes it possible to have several windows side-by-side. The default wrapping on such devices looks ugly. Therefore, please limit all lines to a maximum of 79 characters. For flowing long blocks of text (docstrings or comments), limiting the length to 72 characters is recommended. """ line = physical_line.rstrip() length = len(line) if length > MAX_LINE_LENGTH: try: # The line could contain multi-byte characters if not hasattr(line, 'decode'): # Python 3 line = line.encode('latin-1') length = len(line.decode('utf-8')) except UnicodeDecodeError: pass if length > MAX_LINE_LENGTH: return MAX_LINE_LENGTH, "E501 line too long (%d characters)" % length ############################################################################## # Plugins (check functions) for logical lines ############################################################################## def blank_lines(logical_line, blank_lines, indent_level, line_number, previous_logical, previous_indent_level, blank_lines_before_comment): r""" Separate top-level function and class definitions with two blank lines. Method definitions inside a class are separated by a single blank line. Extra blank lines may be used (sparingly) to separate groups of related functions. Blank lines may be omitted between a bunch of related one-liners (e.g. a set of dummy implementations). Use blank lines in functions, sparingly, to indicate logical sections. Okay: def a():\n pass\n\n\ndef b():\n pass Okay: def a():\n pass\n\n\n# Foo\n# Bar\n\ndef b():\n pass E301: class Foo:\n b = 0\n def bar():\n pass E302: def a():\n pass\n\ndef b(n):\n pass E303: def a():\n pass\n\n\n\ndef b(n):\n pass E303: def a():\n\n\n\n pass E304: @decorator\n\ndef a():\n pass """ if line_number == 1: return # Don't expect blank lines before the first line max_blank_lines = max(blank_lines, blank_lines_before_comment) if previous_logical.startswith('@'): if max_blank_lines: return 0, "E304 blank lines found after function decorator" elif max_blank_lines > 2 or (indent_level and max_blank_lines == 2): return 0, "E303 too many blank lines (%d)" % max_blank_lines elif (logical_line.startswith('def ') or logical_line.startswith('class ') or logical_line.startswith('@')): if indent_level: if not (max_blank_lines or previous_indent_level < indent_level or DOCSTRING_REGEX.match(previous_logical)): return 0, "E301 expected 1 blank line, found 0" elif max_blank_lines != 2: return 0, "E302 expected 2 blank lines, found %d" % max_blank_lines def extraneous_whitespace(logical_line): """ Avoid extraneous whitespace in the following situations: - Immediately inside parentheses, brackets or braces. - Immediately before a comma, semicolon, or colon. Okay: spam(ham[1], {eggs: 2}) E201: spam( ham[1], {eggs: 2}) E201: spam(ham[ 1], {eggs: 2}) E201: spam(ham[1], { eggs: 2}) E202: spam(ham[1], {eggs: 2} ) E202: spam(ham[1 ], {eggs: 2}) E202: spam(ham[1], {eggs: 2 }) E203: if x == 4: print x, y; x, y = y , x E203: if x == 4: print x, y ; x, y = y, x E203: if x == 4 : print x, y; x, y = y, x """ line = logical_line for match in EXTRANEOUS_WHITESPACE_REGEX.finditer(line): text = match.group() char = text.strip() found = match.start() if text == char + ' ' and char in '([{': return found + 1, "E201 whitespace after '%s'" % char if text == ' ' + char and line[found - 1] != ',': if char in '}])': return found, "E202 whitespace before '%s'" % char if char in ',;:': return found, "E203 whitespace before '%s'" % char def missing_whitespace(logical_line): """ JCR: Each comma, semicolon or colon should be followed by whitespace. Okay: [a, b] Okay: (3,) Okay: a[1:4] Okay: a[:4] Okay: a[1:] Okay: a[1:4:2] E231: ['a','b'] E231: foo(bar,baz) """ line = logical_line for index in range(len(line) - 1): char = line[index] if char in ',;:' and line[index + 1] not in WHITESPACE: before = line[:index] if char == ':' and before.count('[') > before.count(']'): continue # Slice syntax, no space required if char == ',' and line[index + 1] == ')': continue # Allow tuple with only one element: (3,) return index, "E231 missing whitespace after '%s'" % char def indentation(logical_line, previous_logical, indent_char, indent_level, previous_indent_level): r""" Use 4 spaces per indentation level. For really old code that you don't want to mess up, you can continue to use 8-space tabs. Okay: a = 1 Okay: if a == 0:\n a = 1 E111: a = 1 Okay: for item in items:\n pass E112: for item in items:\npass Okay: a = 1\nb = 2 E113: a = 1\n b = 2 """ if indent_char == ' ' and indent_level % 4: return 0, "E111 indentation is not a multiple of four" indent_expect = previous_logical.endswith(':') if indent_expect and indent_level <= previous_indent_level: return 0, "E112 expected an indented block" if indent_level > previous_indent_level and not indent_expect: return 0, "E113 unexpected indentation" def whitespace_before_parameters(logical_line, tokens): """ Avoid extraneous whitespace in the following situations: - Immediately before the open parenthesis that starts the argument list of a function call. - Immediately before the open parenthesis that starts an indexing or slicing. Okay: spam(1) E211: spam (1) Okay: dict['key'] = list[index] E211: dict ['key'] = list[index] E211: dict['key'] = list [index] """ prev_type = tokens[0][0] prev_text = tokens[0][1] prev_end = tokens[0][3] for index in range(1, len(tokens)): token_type, text, start, end, line = tokens[index] if (token_type == tokenize.OP and text in '([' and start != prev_end and (prev_type == tokenize.NAME or prev_text in '}])') and # Syntax "class A (B):" is allowed, but avoid it (index < 2 or tokens[index - 2][1] != 'class') and # Allow "return (a.foo for a in range(5))" (not keyword.iskeyword(prev_text))): return prev_end, "E211 whitespace before '%s'" % text prev_type = token_type prev_text = text prev_end = end def whitespace_around_operator(logical_line): """ Avoid extraneous whitespace in the following situations: - More than one space around an assignment (or other) operator to align it with another. Okay: a = 12 + 3 E221: a = 4 + 5 E222: a = 4 + 5 E223: a = 4\t+ 5 E224: a = 4 +\t5 """ for match in WHITESPACE_AROUND_OPERATOR_REGEX.finditer(logical_line): before, whitespace, after = match.groups() tab = whitespace == '\t' offset = match.start(2) if before in OPERATORS: return offset, (tab and "E224 tab after operator" or "E222 multiple spaces after operator") elif after in OPERATORS: return offset, (tab and "E223 tab before operator" or "E221 multiple spaces before operator") def missing_whitespace_around_operator(logical_line, tokens): r""" - Always surround these binary operators with a single space on either side: assignment (=), augmented assignment (+=, -= etc.), comparisons (==, <, >, !=, <>, <=, >=, in, not in, is, is not), Booleans (and, or, not). - Use spaces around arithmetic operators. Okay: i = i + 1 Okay: submitted += 1 Okay: x = x * 2 - 1 Okay: hypot2 = x * x + y * y Okay: c = (a + b) * (a - b) Okay: foo(bar, key='word', *args, **kwargs) Okay: baz(**kwargs) Okay: negative = -1 Okay: spam(-1) Okay: alpha[:-i] Okay: if not -5 < x < +5:\n pass Okay: lambda *args, **kw: (args, kw) E225: i=i+1 E225: submitted +=1 E225: x = x*2 - 1 E225: hypot2 = x*x + y*y E225: c = (a+b) * (a-b) E225: c = alpha -4 E225: z = x **y """ parens = 0 need_space = False prev_type = tokenize.OP prev_text = prev_end = None for token_type, text, start, end, line in tokens: if token_type in (tokenize.NL, tokenize.NEWLINE, tokenize.ERRORTOKEN): # ERRORTOKEN is triggered by backticks in Python 3000 continue if text in ('(', 'lambda'): parens += 1 elif text == ')': parens -= 1 if need_space: if start != prev_end: need_space = False elif text == '>' and prev_text == '<': # Tolerate the "<>" operator, even if running Python 3 pass else: return prev_end, "E225 missing whitespace around operator" elif token_type == tokenize.OP and prev_end is not None: if text == '=' and parens: # Allow keyword args or defaults: foo(bar=None). pass elif text in BINARY_OPERATORS: need_space = True elif text in UNARY_OPERATORS: # Allow unary operators: -123, -x, +1. # Allow argument unpacking: foo(*args, **kwargs). if prev_type == tokenize.OP: if prev_text in '}])': need_space = True elif prev_type == tokenize.NAME: if prev_text not in E225NOT_KEYWORDS: need_space = True else: need_space = True if need_space and start == prev_end: return prev_end, "E225 missing whitespace around operator" prev_type = token_type prev_text = text prev_end = end def whitespace_around_comma(logical_line): """ Avoid extraneous whitespace in the following situations: - More than one space around an assignment (or other) operator to align it with another. JCR: This should also be applied around comma etc. Note: these checks are disabled by default Okay: a = (1, 2) E241: a = (1, 2) E242: a = (1,\t2) """ line = logical_line for separator in ',;:': found = line.find(separator + ' ') if found > -1: return found + 1, "E241 multiple spaces after '%s'" % separator found = line.find(separator + '\t') if found > -1: return found + 1, "E242 tab after '%s'" % separator def whitespace_around_named_parameter_equals(logical_line): """ Don't use spaces around the '=' sign when used to indicate a keyword argument or a default parameter value. Okay: def complex(real, imag=0.0): Okay: return magic(r=real, i=imag) Okay: boolean(a == b) Okay: boolean(a != b) Okay: boolean(a <= b) Okay: boolean(a >= b) E251: def complex(real, imag = 0.0): E251: return magic(r = real, i = imag) """ parens = 0 for match in WHITESPACE_AROUND_NAMED_PARAMETER_REGEX.finditer( logical_line): text = match.group() if parens and len(text) == 3: issue = "E251 no spaces around keyword / parameter equals" return match.start(), issue if text == '(': parens += 1 elif text == ')': parens -= 1 def whitespace_before_inline_comment(logical_line, tokens): """ Separate inline comments by at least two spaces. An inline comment is a comment on the same line as a statement. Inline comments should be separated by at least two spaces from the statement. They should start with a # and a single space. Okay: x = x + 1 # Increment x Okay: x = x + 1 # Increment x E261: x = x + 1 # Increment x E262: x = x + 1 #Increment x E262: x = x + 1 # Increment x """ prev_end = (0, 0) for token_type, text, start, end, line in tokens: if token_type == tokenize.NL: continue if token_type == tokenize.COMMENT: if not line[:start[1]].strip(): continue if prev_end[0] == start[0] and start[1] < prev_end[1] + 2: return (prev_end, "E261 at least two spaces before inline comment") if (len(text) > 1 and text.startswith('# ') or not text.startswith('# ')): return start, "E262 inline comment should start with '# '" else: prev_end = end def imports_on_separate_lines(logical_line): r""" Imports should usually be on separate lines. Okay: import os\nimport sys E401: import sys, os Okay: from subprocess import Popen, PIPE Okay: from myclas import MyClass Okay: from foo.bar.yourclass import YourClass Okay: import myclass Okay: import foo.bar.yourclass """ line = logical_line if line.startswith('import '): found = line.find(',') if found > -1: return found, "E401 multiple imports on one line" def compound_statements(logical_line): r""" Compound statements (multiple statements on the same line) are generally discouraged. While sometimes it's okay to put an if/for/while with a small body on the same line, never do this for multi-clause statements. Also avoid folding such long lines! Okay: if foo == 'blah':\n do_blah_thing() Okay: do_one() Okay: do_two() Okay: do_three() E701: if foo == 'blah': do_blah_thing() E701: for x in lst: total += x E701: while t < 10: t = delay() E701: if foo == 'blah': do_blah_thing() E701: else: do_non_blah_thing() E701: try: something() E701: finally: cleanup() E701: if foo == 'blah': one(); two(); three() E702: do_one(); do_two(); do_three() """ line = logical_line found = line.find(':') if -1 < found < len(line) - 1: before = line[:found] if (before.count('{') <= before.count('}') and # {'a': 1} (dict) before.count('[') <= before.count(']') and # [1:2] (slice) not re.search(r'\blambda\b', before)): # lambda x: x return found, "E701 multiple statements on one line (colon)" found = line.find(';') if -1 < found: return found, "E702 multiple statements on one line (semicolon)" def python_3000_has_key(logical_line): """ The {}.has_key() method will be removed in the future version of Python. Use the 'in' operation instead, like: d = {"a": 1, "b": 2} if "b" in d: print d["b"] """ pos = logical_line.find('.has_key(') if pos > -1: return pos, "W601 .has_key() is deprecated, use 'in'" def python_3000_raise_comma(logical_line): """ When raising an exception, use "raise ValueError('message')" instead of the older form "raise ValueError, 'message'". The paren-using form is preferred because when the exception arguments are long or include string formatting, you don't need to use line continuation characters thanks to the containing parentheses. The older form will be removed in Python 3000. """ match = RAISE_COMMA_REGEX.match(logical_line) if match: return match.start(1), "W602 deprecated form of raising exception" def python_3000_not_equal(logical_line): """ != can also be written <>, but this is an obsolete usage kept for backwards compatibility only. New code should always use !=. The older syntax is removed in Python 3000. """ pos = logical_line.find('<>') if pos > -1: return pos, "W603 '<>' is deprecated, use '!='" def python_3000_backticks(logical_line): """ Backticks are removed in Python 3000. Use repr() instead. """ pos = logical_line.find('`') if pos > -1: return pos, "W604 backticks are deprecated, use 'repr()'" ############################################################################## # Helper functions ############################################################################## if '' == ''.encode(): # Python 2: implicit encoding. def readlines(filename): return open(filename).readlines() else: # Python 3: decode to latin-1. # This function is lazy, it does not read the encoding declaration. # XXX: use tokenize.detect_encoding() def readlines(filename): return open(filename, encoding='latin-1').readlines() def expand_indent(line): """ Return the amount of indentation. Tabs are expanded to the next multiple of 8. >>> expand_indent(' ') 4 >>> expand_indent('\\t') 8 >>> expand_indent(' \\t') 8 >>> expand_indent(' \\t') 8 >>> expand_indent(' \\t') 16 """ result = 0 for char in line: if char == '\t': result = result // 8 * 8 + 8 elif char == ' ': result += 1 else: break return result def mute_string(text): """ Replace contents with 'xxx' to prevent syntax matching. >>> mute_string('"abc"') '"xxx"' >>> mute_string("'''abc'''") "'''xxx'''" >>> mute_string("r'abc'") "r'xxx'" """ start = 1 end = len(text) - 1 # String modifiers (e.g. u or r) if text.endswith('"'): start += text.index('"') elif text.endswith("'"): start += text.index("'") # Triple quotes if text.endswith('"""') or text.endswith("'''"): start += 2 end -= 2 return text[:start] + 'x' * (end - start) + text[end:] def message(text): """Print a message.""" # print >> sys.stderr, options.prog + ': ' + text # print >> sys.stderr, text print(text) ############################################################################## # Framework to run all checks ############################################################################## def find_checks(argument_name): """ Find all globally visible functions where the first argument name starts with argument_name. """ checks = [] for name, function in globals().items(): if not inspect.isfunction(function): continue args = inspect.getargspec(function)[0] if args and args[0].startswith(argument_name): codes = ERRORCODE_REGEX.findall(inspect.getdoc(function) or '') for code in codes or ['']: if not code or not ignore_code(code): checks.append((name, function, args)) break checks.sort() return checks class Checker(object): """ Load a Python source file, tokenize it, check coding style. """ def __init__(self, filename, lines=None): self.filename = filename if filename is None: self.filename = 'stdin' self.lines = lines or [] elif lines is None: self.lines = readlines(filename) else: self.lines = lines options.counters['physical lines'] += len(self.lines) def readline(self): """ Get the next line from the input buffer. """ self.line_number += 1 if self.line_number > len(self.lines): return '' return self.lines[self.line_number - 1] def readline_check_physical(self): """ Check and return the next physical line. This method can be used to feed tokenize.generate_tokens. """ line = self.readline() if line: self.check_physical(line) return line def run_check(self, check, argument_names): """ Run a check plugin. """ arguments = [] for name in argument_names: arguments.append(getattr(self, name)) return check(*arguments) def check_physical(self, line): """ Run all physical checks on a raw input line. """ self.physical_line = line if self.indent_char is None and len(line) and line[0] in ' \t': self.indent_char = line[0] for name, check, argument_names in options.physical_checks: result = self.run_check(check, argument_names) if result is not None: offset, text = result self.report_error(self.line_number, offset, text, check) def build_tokens_line(self): """ Build a logical line from tokens. """ self.mapping = [] logical = [] length = 0 previous = None for token in self.tokens: token_type, text = token[0:2] if token_type in SKIP_TOKENS: continue if token_type == tokenize.STRING: text = mute_string(text) if previous: end_line, end = previous[3] start_line, start = token[2] if end_line != start_line: # different row prev_text = self.lines[end_line - 1][end - 1] if prev_text == ',' or (prev_text not in '{[(' and text not in '}])'): logical.append(' ') length += 1 elif end != start: # different column fill = self.lines[end_line - 1][end:start] logical.append(fill) length += len(fill) self.mapping.append((length, token)) logical.append(text) length += len(text) previous = token self.logical_line = ''.join(logical) assert self.logical_line.lstrip() == self.logical_line assert self.logical_line.rstrip() == self.logical_line def check_logical(self): """ Build a line from tokens and run all logical checks on it. """ options.counters['logical lines'] += 1 self.build_tokens_line() first_line = self.lines[self.mapping[0][1][2][0] - 1] indent = first_line[:self.mapping[0][1][2][1]] self.previous_indent_level = self.indent_level self.indent_level = expand_indent(indent) if options.verbose >= 2: print(self.logical_line[:80].rstrip()) for name, check, argument_names in options.logical_checks: if options.verbose >= 4: print(' ' + name) result = self.run_check(check, argument_names) if result is not None: offset, text = result if isinstance(offset, tuple): original_number, original_offset = offset else: for token_offset, token in self.mapping: if offset >= token_offset: original_number = token[2][0] original_offset = (token[2][1] + offset - token_offset) self.report_error(original_number, original_offset, text, check) self.previous_logical = self.logical_line def check_all(self, expected=None, line_offset=0): """ Run all checks on the input file. """ self.expected = expected or () self.line_offset = line_offset self.line_number = 0 self.file_errors = 0 self.indent_char = None self.indent_level = 0 self.previous_logical = '' self.blank_lines = 0 self.blank_lines_before_comment = 0 self.tokens = [] parens = 0 for token in tokenize.generate_tokens(self.readline_check_physical): if options.verbose >= 3: if token[2][0] == token[3][0]: pos = '[%s:%s]' % (token[2][1] or '', token[3][1]) else: pos = 'l.%s' % token[3][0] print('l.%s\t%s\t%s\t%r' % (token[2][0], pos, tokenize.tok_name[token[0]], token[1])) self.tokens.append(token) token_type, text = token[0:2] if token_type == tokenize.OP and text in '([{': parens += 1 if token_type == tokenize.OP and text in '}])': parens -= 1 if token_type == tokenize.NEWLINE and not parens: self.check_logical() self.blank_lines = 0 self.blank_lines_before_comment = 0 self.tokens = [] if token_type == tokenize.NL and not parens: if len(self.tokens) <= 1: # The physical line contains only this token. self.blank_lines += 1 self.tokens = [] if token_type == tokenize.COMMENT: source_line = token[4] token_start = token[2][1] if source_line[:token_start].strip() == '': self.blank_lines_before_comment = max(self.blank_lines, self.blank_lines_before_comment) self.blank_lines = 0 if text.endswith('\n') and not parens: # The comment also ends a physical line. This works around # Python < 2.6 behaviour, which does not generate NL after # a comment which is on a line by itself. self.tokens = [] return self.file_errors def report_error(self, line_number, offset, text, check): """ Report an error, according to options. """ code = text[:4] if ignore_code(code): return if options.quiet == 1 and not self.file_errors: message(self.filename) if code in options.counters: options.counters[code] += 1 else: options.counters[code] = 1 options.messages[code] = text[5:] if options.quiet or code in self.expected: # Don't care about expected errors or warnings return self.file_errors += 1 if options.counters[code] == 1 or options.repeat: message("%s:%s:%d: %s" % (self.filename, self.line_offset + line_number, offset + 1, text)) if options.show_source: line = self.lines[line_number - 1] message(line.rstrip()) message(' ' * offset + '^') if options.show_pep8: message(check.__doc__.lstrip('\n').rstrip()) def input_file(filename): """ Run all checks on a Python source file. """ if options.verbose: message('checking ' + filename) errors = Checker(filename).check_all() def input_dir(dirname, runner=None): """ Check all Python source files in this directory and all subdirectories. """ dirname = dirname.rstrip('/') if excluded(dirname): return if runner is None: runner = input_file for root, dirs, files in os.walk(dirname): if options.verbose: message('directory ' + root) options.counters['directories'] += 1 dirs.sort() for subdir in dirs: if excluded(subdir): dirs.remove(subdir) files.sort() for filename in files: if filename_match(filename) and not excluded(filename): options.counters['files'] += 1 runner(os.path.join(root, filename)) def excluded(filename): """ Check if options.exclude contains a pattern that matches filename. """ basename = os.path.basename(filename) for pattern in options.exclude: if fnmatch(basename, pattern): # print basename, 'excluded because it matches', pattern return True def filename_match(filename): """ Check if options.filename contains a pattern that matches filename. If options.filename is unspecified, this always returns True. """ if not options.filename: return True for pattern in options.filename: if fnmatch(filename, pattern): return True def ignore_code(code): """ Check if options.ignore contains a prefix of the error code. If options.select contains a prefix of the error code, do not ignore it. """ for select in options.select: if code.startswith(select): return False for ignore in options.ignore: if code.startswith(ignore): return True def reset_counters(): for key in list(options.counters.keys()): if key not in BENCHMARK_KEYS: del options.counters[key] options.messages = {} def get_error_statistics(): """Get error statistics.""" return get_statistics("E") def get_warning_statistics(): """Get warning statistics.""" return get_statistics("W") def get_statistics(prefix=''): """ Get statistics for message codes that start with the prefix. prefix='' matches all errors and warnings prefix='E' matches all errors prefix='W' matches all warnings prefix='E4' matches all errors that have to do with imports """ stats = [] keys = list(options.messages.keys()) keys.sort() for key in keys: if key.startswith(prefix): stats.append('%-7s %s %s' % (options.counters[key], key, options.messages[key])) return stats def get_count(prefix=''): """Return the total count of errors and warnings.""" keys = list(options.messages.keys()) count = 0 for key in keys: if key.startswith(prefix): count += options.counters[key] return count def print_statistics(prefix=''): """Print overall statistics (number of errors and warnings).""" for line in get_statistics(prefix): print(line) def print_benchmark(elapsed): """ Print benchmark numbers. """ print('%-7.2f %s' % (elapsed, 'seconds elapsed')) for key in BENCHMARK_KEYS: print('%-7d %s per second (%d total)' % ( options.counters[key] / elapsed, key, options.counters[key])) def run_tests(filename): """ Run all the tests from a file. A test file can provide many tests. Each test starts with a declaration. This declaration is a single line starting with '#:'. It declares codes of expected failures, separated by spaces or 'Okay' if no failure is expected. If the file does not contain such declaration, it should pass all tests. If the declaration is empty, following lines are not checked, until next declaration. Examples: * Only E224 and W701 are expected: #: E224 W701 * Following example is conform: #: Okay * Don't check these lines: #: """ lines = readlines(filename) + ['#:\n'] line_offset = 0 codes = ['Okay'] testcase = [] for index, line in enumerate(lines): if not line.startswith('#:'): if codes: # Collect the lines of the test case testcase.append(line) continue if codes and index > 0: label = '%s:%s:1' % (filename, line_offset + 1) codes = [c for c in codes if c != 'Okay'] # Run the checker errors = Checker(filename, testcase).check_all(codes, line_offset) # Check if the expected errors were found for code in codes: if not options.counters.get(code): errors += 1 message('%s: error %s not found' % (label, code)) if options.verbose and not errors: message('%s: passed (%s)' % (label, ' '.join(codes))) # Keep showing errors for multiple tests reset_counters() # output the real line numbers line_offset = index # configure the expected errors codes = line.split()[1:] # empty the test case buffer del testcase[:] def selftest(): """ Test all check functions with test cases in docstrings. """ count_passed = 0 count_failed = 0 checks = options.physical_checks + options.logical_checks for name, check, argument_names in checks: for line in check.__doc__.splitlines(): line = line.lstrip() match = SELFTEST_REGEX.match(line) if match is None: continue code, source = match.groups() checker = Checker(None) for part in source.split(r'\n'): part = part.replace(r'\t', '\t') part = part.replace(r'\s', ' ') checker.lines.append(part + '\n') options.quiet = 2 checker.check_all() error = None if code == 'Okay': if len(options.counters) > len(BENCHMARK_KEYS): codes = [key for key in options.counters.keys() if key not in BENCHMARK_KEYS] error = "incorrectly found %s" % ', '.join(codes) elif not options.counters.get(code): error = "failed to find %s" % code # Reset the counters reset_counters() if not error: count_passed += 1 else: count_failed += 1 if len(checker.lines) == 1: print("pep8.py: %s: %s" % (error, checker.lines[0].rstrip())) else: print("pep8.py: %s:" % error) for line in checker.lines: print(line.rstrip()) if options.verbose: print("%d passed and %d failed." % (count_passed, count_failed)) if count_failed: print("Test failed.") else: print("Test passed.") def process_options(arglist=None): """ Process options passed either via arglist or via command line args. """ global options, args parser = OptionParser(version=__version__, usage="%prog [options] input ...") parser.add_option('-v', '--verbose', default=0, action='count', help="print status messages, or debug with -vv") parser.add_option('-q', '--quiet', default=0, action='count', help="report only file names, or nothing with -qq") parser.add_option('-r', '--repeat', action='store_true', help="show all occurrences of the same error") parser.add_option('--exclude', metavar='patterns', default=DEFAULT_EXCLUDE, help="exclude files or directories which match these " "comma separated patterns (default: %s)" % DEFAULT_EXCLUDE) parser.add_option('--filename', metavar='patterns', default='*.py', help="when parsing directories, only check filenames " "matching these comma separated patterns (default: " "*.py)") parser.add_option('--select', metavar='errors', default='', help="select errors and warnings (e.g. E,W6)") parser.add_option('--ignore', metavar='errors', default='', help="skip errors and warnings (e.g. E4,W)") parser.add_option('--show-source', action='store_true', help="show source code for each error") parser.add_option('--show-pep8', action='store_true', help="show text of PEP 8 for each error") parser.add_option('--statistics', action='store_true', help="count errors and warnings") parser.add_option('--count', action='store_true', help="print total number of errors and warnings " "to standard error and set exit code to 1 if " "total is not null") parser.add_option('--benchmark', action='store_true', help="measure processing speed") parser.add_option('--testsuite', metavar='dir', help="run regression tests from dir") parser.add_option('--doctest', action='store_true', help="run doctest on myself") options, args = parser.parse_args(arglist) if options.testsuite: args.append(options.testsuite) if not args and not options.doctest: parser.error('input not specified') options.prog = os.path.basename(sys.argv[0]) options.exclude = options.exclude.split(',') for index in range(len(options.exclude)): options.exclude[index] = options.exclude[index].rstrip('/') if options.filename: options.filename = options.filename.split(',') if options.select: options.select = options.select.split(',') else: options.select = [] if options.ignore: options.ignore = options.ignore.split(',') elif options.select: # Ignore all checks which are not explicitly selected options.ignore = [''] elif options.testsuite or options.doctest: # For doctest and testsuite, all checks are required options.ignore = [] else: # The default choice: ignore controversial checks options.ignore = DEFAULT_IGNORE.split(',') options.physical_checks = find_checks('physical_line') options.logical_checks = find_checks('logical_line') options.counters = dict.fromkeys(BENCHMARK_KEYS, 0) options.messages = {} return options, args def _main(): """ Parse options and run checks on Python source. """ options, args = process_options() if options.doctest: import doctest doctest.testmod(verbose=options.verbose) selftest() if options.testsuite: runner = run_tests else: runner = input_file start_time = time.time() for path in args: if os.path.isdir(path): input_dir(path, runner=runner) elif not excluded(path): options.counters['files'] += 1 runner(path) elapsed = time.time() - start_time if options.statistics: print_statistics() if options.benchmark: print_benchmark(elapsed) count = get_count() if count: if options.count: sys.stderr.write(str(count) + '\n') sys.exit(1) if __name__ == '__main__': _main()