check-code: prepend warning prefix only once, but for each warning

The code adding the prefix is now run once per pattern. It was run once per
file (after the change 3e1e4a8aec1e).
Demonstrate that it is working now by extending the test. Raise two different
warnings, one of them twice.

contrib/check-code.py

@@ -1,546 +1,547 b''
 #!/usr/bin/env python
 #
 # check-code - a style and portability checker for Mercurial
 #
 # Copyright 2010 Matt Mackall <[e-mail]>
 #
 # This software may be used and distributed according to the terms of the
 # GNU General Public License version 2 or any later version.
 
 import re, glob, os, sys
 import keyword
 import optparse
 try:
     import re2
 except ImportError:
     re2 = None
 
 def compilere(pat, multiline=False):
     if multiline:
         pat = '(?m)' + pat
     if re2:
         try:
             return re2.compile(pat)
         except re2.error:
             pass
     return re.compile(pat)
 
 def repquote(m):
     fromc = '.:'
     tochr = 'pq'
     def encodechr(i):
         if i > 255:
             return 'u'
         c = chr(i)
         if c in ' \n':
             return c
         if c.isalpha():
             return 'x'
         if c.isdigit():
             return 'n'
         try:
             return tochr[fromc.find(c)]
         except (ValueError, IndexError):
             return 'o'
     t = m.group('text')
     tt = ''.join(encodechr(i) for i in xrange(256))
     t = t.translate(tt)
     return m.group('quote') + t + m.group('quote')
 
 def reppython(m):
     comment = m.group('comment')
     if comment:
         l = len(comment.rstrip())
         return "#" * l + comment[l:]
     return repquote(m)
 
 def repcomment(m):
     return m.group(1) + "#" * len(m.group(2))
 
 def repccomment(m):
     t = re.sub(r"((?<=\n) )|\S", "x", m.group(2))
     return m.group(1) + t + "*/"
 
 def repcallspaces(m):
     t = re.sub(r"\n\s+", "\n", m.group(2))
     return m.group(1) + t
 
 def repinclude(m):
     return m.group(1) + "<foo>"
 
 def rephere(m):
     t = re.sub(r"\S", "x", m.group(2))
     return m.group(1) + t
 
 
 testpats = [
   [
     (r'pushd|popd', "don't use 'pushd' or 'popd', use 'cd'"),
     (r'\W\$?\(\([^\)\n]*\)\)', "don't use (()) or $(()), use 'expr'"),
     (r'grep.*-q', "don't use 'grep -q', redirect to /dev/null"),
     (r'(?<!hg )grep.*-a', "don't use 'grep -a', use in-line python"),
     (r'sed.*-i', "don't use 'sed -i', use a temporary file"),
     (r'\becho\b.*\\n', "don't use 'echo \\n', use printf"),
     (r'echo -n', "don't use 'echo -n', use printf"),
     (r'(^| )wc[^|]*$\n(?!.*\(re\))', "filter wc output"),
     (r'head -c', "don't use 'head -c', use 'dd'"),
     (r'tail -n', "don't use the '-n' option to tail, just use '-<num>'"),
     (r'sha1sum', "don't use sha1sum, use $TESTDIR/md5sum.py"),
     (r'ls.*-\w*R', "don't use 'ls -R', use 'find'"),
     (r'printf.*[^\\]\\([1-9]|0\d)', "don't use 'printf \NNN', use Python"),
     (r'printf.*[^\\]\\x', "don't use printf \\x, use Python"),
     (r'\$\(.*\)', "don't use $(expr), use `expr`"),
     (r'rm -rf \*', "don't use naked rm -rf, target a directory"),
     (r'(^|\|\s*)grep (-\w\s+)*[^|]*[(|]\w',
      "use egrep for extended grep syntax"),
     (r'/bin/', "don't use explicit paths for tools"),
     (r'[^\n]\Z', "no trailing newline"),
     (r'export.*=', "don't export and assign at once"),
     (r'^source\b', "don't use 'source', use '.'"),
     (r'touch -d', "don't use 'touch -d', use 'touch -t' instead"),
     (r'ls +[^|\n-]+ +-', "options to 'ls' must come before filenames"),
     (r'[^>\n]>\s*\$HGRCPATH', "don't overwrite $HGRCPATH, append to it"),
     (r'^stop\(\)', "don't use 'stop' as a shell function name"),
     (r'(\[|\btest\b).*-e ', "don't use 'test -e', use 'test -f'"),
     (r'^alias\b.*=', "don't use alias, use a function"),
     (r'if\s*!', "don't use '!' to negate exit status"),
     (r'/dev/u?random', "don't use entropy, use /dev/zero"),
     (r'do\s*true;\s*done', "don't use true as loop body, use sleep 0"),
     (r'^( *)\t', "don't use tabs to indent"),
     (r'sed (-e )?\'(\d+|/[^/]*/)i(?!\\\n)',
      "put a backslash-escaped newline after sed 'i' command"),
   ],
   # warnings
   [
     (r'^function', "don't use 'function', use old style"),
     (r'^diff.*-\w*N', "don't use 'diff -N'"),
     (r'\$PWD|\${PWD}', "don't use $PWD, use `pwd`"),
     (r'^([^"\'\n]|("[^"\n]*")|(\'[^\'\n]*\'))*\^', "^ must be quoted"),
     (r'kill (`|\$\()', "don't use kill, use killdaemons.py")
   ]
 ]
 
 testfilters = [
     (r"( *)(#([^\n]*\S)?)", repcomment),
     (r"<<(\S+)((.|\n)*?\n\1)", rephere),
 ]
 
 winglobmsg = "use (glob) to match Windows paths too"
 uprefix = r"^  \$ "
 utestpats = [
   [
     (r'^(\S.*||  [$>] .*)[ \t]\n', "trailing whitespace on non-output"),
     (uprefix + r'.*\|\s*sed[^|>\n]*\n',
      "use regex test output patterns instead of sed"),
     (uprefix + r'(true|exit 0)', "explicit zero exit unnecessary"),
     (uprefix + r'.*(?<!\[)\$\?', "explicit exit code checks unnecessary"),
     (uprefix + r'.*\|\| echo.*(fail|error)',
      "explicit exit code checks unnecessary"),
     (uprefix + r'set -e', "don't use set -e"),
     (uprefix + r'(\s|fi\b|done\b)', "use > for continued lines"),
     (r'^  saved backup bundle to \$TESTTMP.*\.hg$', winglobmsg),
     (r'^  changeset .* references (corrupted|missing) \$TESTTMP/.*[^)]$',
      winglobmsg),
     (r'^  pulling from \$TESTTMP/.*[^)]$', winglobmsg, '\$TESTTMP/unix-repo$'),
     (r'^  reverting .*/.*[^)]$', winglobmsg, '\$TESTTMP/unix-repo$'),
     (r'^  cloning subrepo \S+/.*[^)]$', winglobmsg, '\$TESTTMP/unix-repo$'),
     (r'^  pushing to \$TESTTMP/.*[^)]$', winglobmsg, '\$TESTTMP/unix-repo$'),
     (r'^  pushing subrepo \S+/\S+ to.*[^)]$', winglobmsg,
      '\$TESTTMP/unix-repo$'),
     (r'^  moving \S+/.*[^)]$', winglobmsg),
     (r'^  no changes made to subrepo since.*/.*[^)]$',
      winglobmsg, '\$TESTTMP/unix-repo$'),
     (r'^  .*: largefile \S+ not available from file:.*/.*[^)]$',
      winglobmsg, '\$TESTTMP/unix-repo$'),
   ],
   # warnings
   [
     (r'^  [^*?/\n]* \(glob\)$',
      "glob match with no glob character (?*/)"),
   ]
 ]
 
 for i in [0, 1]:
     for p, m in testpats[i]:
         if p.startswith(r'^'):
             p = r"^  [$>] (%s)" % p[1:]
         else:
             p = r"^  [$>] .*(%s)" % p
         utestpats[i].append((p, m))
 
 utestfilters = [
     (r"<<(\S+)((.|\n)*?\n  > \1)", rephere),
     (r"( *)(#([^\n]*\S)?)", repcomment),
 ]
 
 pypats = [
   [
     (r'^\s*def\s*\w+\s*\(.*,\s*\(',
      "tuple parameter unpacking not available in Python 3+"),
     (r'lambda\s*\(.*,.*\)',
      "tuple parameter unpacking not available in Python 3+"),
     (r'import (.+,[^.]+\.[^.]+|[^.]+\.[^.]+,)',
      '2to3 can\'t always rewrite "import qux, foo.bar", '
      'use "import foo.bar" on its own line instead.'),
     (r'(?<!def)\s+(cmp)\(', "cmp is not available in Python 3+"),
     (r'\breduce\s*\(.*', "reduce is not available in Python 3+"),
     (r'\.has_key\b', "dict.has_key is not available in Python 3+"),
     (r'\s<>\s', '<> operator is not available in Python 3+, use !='),
     (r'^\s*\t', "don't use tabs"),
     (r'\S;\s*\n', "semicolon"),
     (r'[^_]_\("[^"]+"\s*%', "don't use % inside _()"),
     (r"[^_]_\('[^']+'\s*%", "don't use % inside _()"),
     (r'(\w|\)),\w', "missing whitespace after ,"),
     (r'(\w|\))[+/*\-<>]\w', "missing whitespace in expression"),
     (r'^\s+(\w|\.)+=\w[^,()\n]*$', "missing whitespace in assignment"),
     (r'(\s+)try:\n((?:\n|\1\s.*\n)+?)\1except.*?:\n'
      r'((?:\n|\1\s.*\n)+?)\1finally:', 'no try/except/finally in Python 2.4'),
     (r'(?<!def)(\s+|^|\()next\(.+\)',
      'no next(foo) in Python 2.4 and 2.5, use foo.next() instead'),
     (r'(\s+)try:\n((?:\n|\1\s.*\n)*?)\1\s*yield\b.*?'
      r'((?:\n|\1\s.*\n)+?)\1finally:',
      'no yield inside try/finally in Python 2.4'),
     (r'.{81}', "line too long"),
     (r' x+[xo][\'"]\n\s+[\'"]x', 'string join across lines with no space'),
     (r'[^\n]\Z', "no trailing newline"),
     (r'(\S[ \t]+|^[ \t]+)\n', "trailing whitespace"),
 #    (r'^\s+[^_ \n][^_. \n]+_[^_\n]+\s*=',
 #     "don't use underbars in identifiers"),
     (r'^\s+(self\.)?[A-za-z][a-z0-9]+[A-Z]\w* = ',
      "don't use camelcase in identifiers"),
     (r'^\s*(if|while|def|class|except|try)\s[^[\n]*:\s*[^\\n]#\s]+',
      "linebreak after :"),
     (r'class\s[^( \n]+:', "old-style class, use class foo(object)"),
     (r'class\s[^( \n]+\(\):',
      "class foo() not available in Python 2.4, use class foo(object)"),
     (r'\b(%s)\(' % '|'.join(keyword.kwlist),
      "Python keyword is not a function"),
     (r',]', "unneeded trailing ',' in list"),
 #    (r'class\s[A-Z][^\(]*\((?!Exception)',
 #     "don't capitalize non-exception classes"),
 #    (r'in range\(', "use xrange"),
 #    (r'^\s*print\s+', "avoid using print in core and extensions"),
     (r'[\x80-\xff]', "non-ASCII character literal"),
     (r'("\')\.format\(', "str.format() not available in Python 2.4"),
     (r'^\s*with\s+', "with not available in Python 2.4"),
     (r'\.isdisjoint\(', "set.isdisjoint not available in Python 2.4"),
     (r'^\s*except.* as .*:', "except as not available in Python 2.4"),
     (r'^\s*os\.path\.relpath', "relpath not available in Python 2.4"),
     (r'(?<!def)\s+(any|all|format)\(',
      "any/all/format not available in Python 2.4"),
     (r'(?<!def)\s+(callable)\(',
      "callable not available in Python 3, use getattr(f, '__call__', None)"),
     (r'if\s.*\selse', "if ... else form not available in Python 2.4"),
     (r'^\s*(%s)\s\s' % '|'.join(keyword.kwlist),
      "gratuitous whitespace after Python keyword"),
     (r'([\(\[][ \t]\S)|(\S[ \t][\)\]])', "gratuitous whitespace in () or []"),
 #    (r'\s\s=', "gratuitous whitespace before ="),
     (r'[^>< ](\+=|-=|!=|<>|<=|>=|<<=|>>=|%=)\S',
      "missing whitespace around operator"),
     (r'[^>< ](\+=|-=|!=|<>|<=|>=|<<=|>>=|%=)\s',
      "missing whitespace around operator"),
     (r'\s(\+=|-=|!=|<>|<=|>=|<<=|>>=|%=)\S',
      "missing whitespace around operator"),
     (r'[^^+=*/!<>&| %-](\s=|=\s)[^= ]',
      "wrong whitespace around ="),
     (r'\([^()]*( =[^=]|[^<>!=]= )',
      "no whitespace around = for named parameters"),
     (r'raise Exception', "don't raise generic exceptions"),
     (r'raise [^,(]+, (\([^\)]+\)|[^,\(\)]+)$',
      "don't use old-style two-argument raise, use Exception(message)"),
     (r' is\s+(not\s+)?["\'0-9-]', "object comparison with literal"),
     (r' [=!]=\s+(True|False|None)',
      "comparison with singleton, use 'is' or 'is not' instead"),
     (r'^\s*(while|if) [01]:',
      "use True/False for constant Boolean expression"),
     (r'(?:(?<!def)\s+|\()hasattr',
      'hasattr(foo, bar) is broken, use util.safehasattr(foo, bar) instead'),
     (r'opener\([^)]*\).read\(',
      "use opener.read() instead"),
     (r'BaseException', 'not in Python 2.4, use Exception'),
     (r'os\.path\.relpath', 'os.path.relpath is not in Python 2.5'),
     (r'opener\([^)]*\).write\(',
      "use opener.write() instead"),
     (r'[\s\(](open|file)\([^)]*\)\.read\(',
      "use util.readfile() instead"),
     (r'[\s\(](open|file)\([^)]*\)\.write\(',
      "use util.readfile() instead"),
     (r'^[\s\(]*(open(er)?|file)\([^)]*\)',
      "always assign an opened file to a variable, and close it afterwards"),
     (r'[\s\(](open|file)\([^)]*\)\.',
      "always assign an opened file to a variable, and close it afterwards"),
     (r'(?i)descendent', "the proper spelling is descendAnt"),
     (r'\.debug\(\_', "don't mark debug messages for translation"),
     (r'\.strip\(\)\.split\(\)', "no need to strip before splitting"),
     (r'^\s*except\s*:', "naked except clause", r'#.*re-raises'),
     (r':\n(    )*( ){1,3}[^ ]', "must indent 4 spaces"),
     (r'ui\.(status|progress|write|note|warn)\([\'\"]x',
      "missing _() in ui message (use () to hide false-positives)"),
     (r'release\(.*wlock, .*lock\)', "wrong lock release order"),
   ],
   # warnings
   [
     (r'(^| )pp +xxxxqq[ \n][^\n]', "add two newlines after '.. note::'"),
   ]
 ]
 
 pyfilters = [
     (r"""(?msx)(?P<comment>\#.*?$)|
          ((?P<quote>('''|\"\"\"|(?<!')'(?!')|(?<!")"(?!")))
           (?P<text>(([^\\]|\\.)*?))
           (?P=quote))""", reppython),
 ]
 
 txtfilters = []
 
 txtpats = [
   [
     ('\s$', 'trailing whitespace'),
   ],
   []
 ]
 
 cpats = [
   [
     (r'//', "don't use //-style comments"),
     (r'^  ', "don't use spaces to indent"),
     (r'\S\t', "don't use tabs except for indent"),
     (r'(\S[ \t]+|^[ \t]+)\n', "trailing whitespace"),
     (r'.{81}', "line too long"),
     (r'(while|if|do|for)\(', "use space after while/if/do/for"),
     (r'return\(', "return is not a function"),
     (r' ;', "no space before ;"),
     (r'[)][{]', "space between ) and {"),
     (r'\w+\* \w+', "use int *foo, not int* foo"),
     (r'\W\([^\)]+\) \w+', "use (int)foo, not (int) foo"),
     (r'\w+ (\+\+|--)', "use foo++, not foo ++"),
     (r'\w,\w', "missing whitespace after ,"),
     (r'^[^#]\w[+/*]\w', "missing whitespace in expression"),
     (r'^#\s+\w', "use #foo, not # foo"),
     (r'[^\n]\Z', "no trailing newline"),
     (r'^\s*#import\b', "use only #include in standard C code"),
   ],
   # warnings
   []
 ]
 
 cfilters = [
     (r'(/\*)(((\*(?!/))|[^*])*)\*/', repccomment),
     (r'''(?P<quote>(?<!")")(?P<text>([^"]|\\")+)"(?!")''', repquote),
     (r'''(#\s*include\s+<)([^>]+)>''', repinclude),
     (r'(\()([^)]+\))', repcallspaces),
 ]
 
 inutilpats = [
   [
     (r'\bui\.', "don't use ui in util"),
   ],
   # warnings
   []
 ]
 
 inrevlogpats = [
   [
     (r'\brepo\.', "don't use repo in revlog"),
   ],
   # warnings
   []
 ]
 
 checks = [
     ('python', r'.*\.(py|cgi)$', pyfilters, pypats),
     ('test script', r'(.*/)?test-[^.~]*$', testfilters, testpats),
     ('c', r'.*\.[ch]$', cfilters, cpats),
     ('unified test', r'.*\.t$', utestfilters, utestpats),
     ('layering violation repo in revlog', r'mercurial/revlog\.py', pyfilters,
      inrevlogpats),
     ('layering violation ui in util', r'mercurial/util\.py', pyfilters,
      inutilpats),
     ('txt', r'.*\.txt$', txtfilters, txtpats),
 ]
 
 def _preparepats():
     for c in checks:
         failandwarn = c[-1]
         for pats in failandwarn:
             for i, pseq in enumerate(pats):
                 # fix-up regexes for multi-line searches
                 p = pseq[0]
                 # \s doesn't match \n
                 p = re.sub(r'(?<!\\)\\s', r'[ \\t]', p)
                 # [^...] doesn't match newline
                 p = re.sub(r'(?<!\\)\[\^', r'[^\\n', p)
 
                 pats[i] = (re.compile(p, re.MULTILINE),) + pseq[1:]
         filters = c[2]
         for i, flt in enumerate(filters):
             filters[i] = re.compile(flt[0]), flt[1]
 _preparepats()
 
 class norepeatlogger(object):
     def __init__(self):
         self._lastseen = None
 
     def log(self, fname, lineno, line, msg, blame):
         """print error related a to given line of a given file.
 
         The faulty line will also be printed but only once in the case
         of multiple errors.
 
         :fname: filename
         :lineno: line number
         :line: actual content of the line
         :msg: error message
         """
         msgid = fname, lineno, line
         if msgid != self._lastseen:
             if blame:
                 print "%s:%d (%s):" % (fname, lineno, blame)
             else:
                 print "%s:%d:" % (fname, lineno)
             print " > %s" % line
             self._lastseen = msgid
         print " " + msg
 
 _defaultlogger = norepeatlogger()
 
 def getblame(f):
     lines = []
     for l in os.popen('hg annotate -un %s' % f):
         start, line = l.split(':', 1)
         user, rev = start.split()
         lines.append((line[1:-1], user, rev))
     return lines
 
 def checkfile(f, logfunc=_defaultlogger.log, maxerr=None, warnings=False,
               blame=False, debug=False, lineno=True):
     """checks style and portability of a given file
 
     :f: filepath
     :logfunc: function used to report error
               logfunc(filename, linenumber, linecontent, errormessage)
     :maxerr: number of error to display before aborting.
              Set to false (default) to report all errors
 
     return True if no error is found, False otherwise.
     """
     blamecache = None
     result = True
     for name, match, filters, pats in checks:
         if debug:
             print name, f
         fc = 0
         if not re.match(match, f):
             if debug:
                 print "Skipping %s for %s it doesn't match %s" % (
                        name, match, f)
             continue
         try:
             fp = open(f)
         except IOError, e:
             print "Skipping %s, %s" % (f, str(e).split(':', 1)[0])
             continue
         pre = post = fp.read()
         fp.close()
         if "no-" "check-code" in pre:
             if debug:
                 print "Skipping %s for %s it has no-" "check-code" % (
                        name, f)
             break
         for p, r in filters:
             post = re.sub(p, r, post)
         nerrs = len(pats[0]) # nerr elements are errors
         if warnings:
             pats = pats[0] + pats[1]
         else:
             pats = pats[0]
         # print post # uncomment to show filtered version
 
         if debug:
             print "Checking %s for %s" % (name, f)
 
         prelines = None
         errors = []
         for i, pat in enumerate(pats):
             if len(pat) == 3:
                 p, msg, ignore = pat
             else:
                 p, msg = pat
                 ignore = None
+            if i >= nerrs:
+                msg = "warning: " + msg
 
             pos = 0
             n = 0
             for m in p.finditer(post):
                 if prelines is None:
                     prelines = pre.splitlines()
                     postlines = post.splitlines(True)
 
                 start = m.start()
                 while n < len(postlines):
                     step = len(postlines[n])
                     if pos + step > start:
                         break
                     pos += step
                     n += 1
                 l = prelines[n]
 
                 if "check-code" "-ignore" in l:
                     if debug:
                         print "Skipping %s for %s:%s (check-code" "-ignore)" % (
                             name, f, n)
                     continue
                 elif ignore and re.search(ignore, l, re.MULTILINE):
                     continue
                 bd = ""
                 if blame:
                     bd = 'working directory'
                     if not blamecache:
                         blamecache = getblame(f)
                     if n < len(blamecache):
                         bl, bu, br = blamecache[n]
                         if bl == l:
                             bd = '%s@%s' % (bu, br)
-                if i >= nerrs:
-                    msg = "warning: " + msg
+
                 errors.append((f, lineno and n + 1, l, msg, bd))
                 result = False
 
         errors.sort()
         for e in errors:
             logfunc(*e)
             fc += 1
             if maxerr and fc >= maxerr:
                 print " (too many errors, giving up)"
                 break
 
     return result
 
 if __name__ == "__main__":
     parser = optparse.OptionParser("%prog [options] [files]")
     parser.add_option("-w", "--warnings", action="store_true",
                       help="include warning-level checks")
     parser.add_option("-p", "--per-file", type="int",
                       help="max warnings per file")
     parser.add_option("-b", "--blame", action="store_true",
                       help="use annotate to generate blame info")
     parser.add_option("", "--debug", action="store_true",
                       help="show debug information")
     parser.add_option("", "--nolineno", action="store_false",
                       dest='lineno', help="don't show line numbers")
 
     parser.set_defaults(per_file=15, warnings=False, blame=False, debug=False,
                         lineno=True)
     (options, args) = parser.parse_args()
 
     if len(args) == 0:
         check = glob.glob("*")
     else:
         check = args
 
     ret = 0
     for f in check:
         if not checkfile(f, maxerr=options.per_file, warnings=options.warnings,
                          blame=options.blame, debug=options.debug,
                          lineno=options.lineno):
             ret = 1
     sys.exit(ret)

tests/test-check-code.t

@@ -1,245 +1,253 b''
   $ cat > correct.py <<EOF
   > def toto(arg1, arg2):
   >     del arg2
   >     return (5 + 6, 9)
   > EOF
   $ cat > wrong.py <<EOF
   > def toto( arg1, arg2):
   >     del(arg2)
   >     return ( 5+6, 9)
   > EOF
   $ cat > quote.py <<EOF
   > # let's use quote in comments
   > (''' ( 4x5 )
   > but """\\''' and finally''',
   > """let's fool checkpatch""", '1+2',
   > '"""', 42+1, """and
   > ( 4-1 ) """, "( 1+1 )\" and ")
   > a, '\\\\\\\\', "\\\\\\" x-2", "c-1"
   > EOF
   $ cat > non-py24.py <<EOF
   > # Using builtins that does not exist in Python 2.4
   > if any():
   >     x = all()
   >     y = format(x)
   >     # next(generator) is new in 2.6
   >     z = next(x)
   >     # but generator.next() is okay
   >     x.next()
   >     # and we can make our own next
   >     def next(stuff):
   >         pass
   > 
   > # Do not complain about our own definition
   > def any(x):
   >     pass
   > 
   > # try/except/finally block does not exist in Python 2.4
   >     try:
   >         pass
   >     except StandardError, inst:
   >         pass
   >     finally:
   >         pass
   > 
   > # nested try/finally+try/except is allowed
   >     try:
   >         try:
   >             pass
   >         except StandardError, inst:
   >             pass
   >     finally:
   >         pass
   > 
   > # yield inside a try/finally block is not allowed in Python 2.4
   >     try:
   >         pass
   >         yield 1
   >     finally:
   >         pass
   >     try:
   >         yield
   >         pass
   >     finally:
   >         pass
   > 
   > EOF
   $ cat > classstyle.py <<EOF
   > class newstyle_class(object):
   >     pass
   > 
   > class oldstyle_class:
   >     pass
   > 
   > class empty():
   >     pass
   > 
   > no_class = 1:
   >     pass
   > EOF
   $ check_code="$TESTDIR"/../contrib/check-code.py
   $ "$check_code" ./wrong.py ./correct.py ./quote.py ./non-py24.py ./classstyle.py
   ./wrong.py:1:
    > def toto( arg1, arg2):
    gratuitous whitespace in () or []
   ./wrong.py:2:
    >     del(arg2)
    Python keyword is not a function
   ./wrong.py:3:
    >     return ( 5+6, 9)
    gratuitous whitespace in () or []
    missing whitespace in expression
   ./quote.py:5:
    > '"""', 42+1, """and
    missing whitespace in expression
   ./non-py24.py:2:
    > if any():
    any/all/format not available in Python 2.4
   ./non-py24.py:3:
    >     x = all()
    any/all/format not available in Python 2.4
   ./non-py24.py:4:
    >     y = format(x)
    any/all/format not available in Python 2.4
   ./non-py24.py:6:
    >     z = next(x)
    no next(foo) in Python 2.4 and 2.5, use foo.next() instead
   ./non-py24.py:18:
    >     try:
    no try/except/finally in Python 2.4
   ./non-py24.py:35:
    >     try:
    no yield inside try/finally in Python 2.4
   ./non-py24.py:40:
    >     try:
    no yield inside try/finally in Python 2.4
   ./classstyle.py:4:
    > class oldstyle_class:
    old-style class, use class foo(object)
   ./classstyle.py:7:
    > class empty():
    class foo() not available in Python 2.4, use class foo(object)
   [1]
   $ cat > python3-compat.py << EOF
   > foo <> bar
   > reduce(lambda a, b: a + b, [1, 2, 3, 4])
   > EOF
   $ "$check_code" python3-compat.py
   python3-compat.py:1:
    > foo <> bar
    <> operator is not available in Python 3+, use !=
   python3-compat.py:2:
    > reduce(lambda a, b: a + b, [1, 2, 3, 4])
    reduce is not available in Python 3+
   [1]
 
   $ cat > is-op.py <<EOF
   > # is-operator comparing number or string literal
   > x = None
   > y = x is 'foo'
   > y = x is "foo"
   > y = x is 5346
   > y = x is -6
   > y = x is not 'foo'
   > y = x is not "foo"
   > y = x is not 5346
   > y = x is not -6
   > EOF
 
   $ "$check_code" ./is-op.py
   ./is-op.py:3:
    > y = x is 'foo'
    object comparison with literal
   ./is-op.py:4:
    > y = x is "foo"
    object comparison with literal
   ./is-op.py:5:
    > y = x is 5346
    object comparison with literal
   ./is-op.py:6:
    > y = x is -6
    object comparison with literal
   ./is-op.py:7:
    > y = x is not 'foo'
    object comparison with literal
   ./is-op.py:8:
    > y = x is not "foo"
    object comparison with literal
   ./is-op.py:9:
    > y = x is not 5346
    object comparison with literal
   ./is-op.py:10:
    > y = x is not -6
    object comparison with literal
   [1]
 
   $ cat > for-nolineno.py <<EOF
   > except:
   > EOF
   $ "$check_code" for-nolineno.py --nolineno
   for-nolineno.py:0:
    > except:
    naked except clause
   [1]
 
   $ cat > warning.t <<EOF
   >   $ function warnonly {
   >   > }
+  >   $ diff -N aaa
+  >   $ function onwarn {}
   > EOF
   $ "$check_code" warning.t
   $ "$check_code" --warn warning.t
   warning.t:1:
    >   $ function warnonly {
    warning: don't use 'function', use old style
+  warning.t:3:
+   >   $ diff -N aaa
+   warning: don't use 'diff -N'
+  warning.t:4:
+   >   $ function onwarn {}
+   warning: don't use 'function', use old style
   [1]
   $ cat > raise-format.py <<EOF
   > raise SomeException, message
   > # this next line is okay
   > raise SomeException(arg1, arg2)
   > EOF
   $ "$check_code" not-existing.py raise-format.py
   Skipping*not-existing.py* (glob)
   raise-format.py:1:
    > raise SomeException, message
    don't use old-style two-argument raise, use Exception(message)
   [1]
 
   $ cat > rst.py <<EOF
   > """problematic rst text
   > 
   > .. note::
   >     wrong
   > """
   > 
   > '''
   > 
   > .. note::
   > 
   >     valid
   > 
   > new text
   > 
   >     .. note::
   > 
   >         also valid
   > '''
   > 
   > """mixed
   > 
   > .. note::
   > 
   >   good
   > 
   >     .. note::
   >         plus bad
   > """
   > EOF
   $ $check_code -w rst.py
   rst.py:3:
    > .. note::
    warning: add two newlines after '.. note::'
   rst.py:26:
    >     .. note::
    warning: add two newlines after '.. note::'
   [1]