Moving swap IWYU from <algorithm> to <utility>.

cpplint.py

 #!/usr/bin/env python
 #
 # Copyright (c) 2009 Google Inc. All rights reserved.
 #
 # Redistribution and use in source and binary forms, with or without
 # modification, are permitted provided that the following conditions are
 # met:
 #
 #    * Redistributions of source code must retain the above copyright
 # notice, this list of conditions and the following disclaimer.
@@ skipping 1648 matching lines @@
     named file.
 
   """
 
   # Restores original filename in case that cpplint is invoked from Emacs's
   # flymake.
   filename = re.sub(r'_flymake\.h$', '.h', filename)
   filename = re.sub(r'/\.flymake/([^/]*)$', r'/\1', filename)
   # Replace 'c++' with 'cpp'.
   filename = filename.replace('C++', 'cpp').replace('c++', 'cpp')
-  
+
   fileinfo = FileInfo(filename)
   file_path_from_root = fileinfo.RepositoryName()
   if _root:
     file_path_from_root = re.sub('^' + _root + os.sep, '', file_path_from_root)
   return re.sub(r'[^a-zA-Z0-9]', '_', file_path_from_root).upper() + '_'
 
 
 def CheckForHeaderGuard(filename, clean_lines, error):
   """Checks that the file contains a header guard.
 
@@ skipping 3107 matching lines @@
     return
 
   # Reset include state across preprocessor directives.  This is meant
   # to silence warnings for conditional includes.
   match = Match(r'^\s*#\s*(if|ifdef|ifndef|elif|else|endif)\b', line)
   if match:
     include_state.ResetSection(match.group(1))
 
   # Make Windows paths like Unix.
   fullname = os.path.abspath(filename).replace('\\', '/')
-  
+
   # Perform other checks now that we are sure that this is not an include line
   CheckCasts(filename, clean_lines, linenum, error)
   CheckGlobalStatic(filename, clean_lines, linenum, error)
   CheckPrintf(filename, clean_lines, linenum, error)
 
   if file_extension == 'h':
     # TODO(unknown): check that 1-arg constructors are explicit.
     #                How to tell it's a constructor?
     #                (handled in CheckForNonStandardConstructs for now)
     # TODO(unknown): check that classes declare or disable copy/assign
@@ skipping 683 matching lines @@
     ('<utility>', ('pair',)),
     ('<vector>', ('vector',)),
 
     # gcc extensions.
     # Note: std::hash is their hash, ::hash is our hash
     ('<hash_map>', ('hash_map', 'hash_multimap',)),
     ('<hash_set>', ('hash_set', 'hash_multiset',)),
     ('<slist>', ('slist',)),
     )
 
+_HEADERS_MAYBE_TEMPLATES = (
+    ('<algorithm>', ('copy', 'max', 'min', 'min_element', 'sort',
+                     'transform',
+                    )),
+    ('<utility>', ('swap',)),
+    )
+
 _RE_PATTERN_STRING = re.compile(r'\bstring\b')
 
-_re_pattern_algorithm_header = []
-for _template in ('copy', 'max', 'min', 'min_element', 'sort', 'swap',
-                  'transform'):
-  # Match max<type>(..., ...), max(..., ...), but not foo->max, foo.max or
-  # type::max().
-  _re_pattern_algorithm_header.append(
-      (re.compile(r'[^>.]\b' + _template + r'(<.*?>)?\([^\)]'),
-       _template,
-       '<algorithm>'))
+_RE_PATTERN_HEADERS_MAYBE_TEMPLATES = []

[Dirk Pranke, 2016/02/05 20:40:38]

this isn't a constant, so I wouldn't use all-caps for the name.

[skym, 2016/02/05 20:52:58]

Done.

+for _header, _templates in _HEADERS_MAYBE_TEMPLATES:
+  for _template in _templates:
+    # Match max<type>(..., ...), max(..., ...), but not foo->max, foo.max or
+    # type::max().
+    _RE_PATTERN_HEADERS_MAYBE_TEMPLATES.append(
+        (re.compile(r'[^>.]\b' + _template + r'(<.*?>)?\([^\)]'),
+            _template,
+            _header))
 
+# Other scripts may reach in and modify this pattern.
 _re_pattern_templates = []
 for _header, _templates in _HEADERS_CONTAINING_TEMPLATES:
   for _template in _templates:
     _re_pattern_templates.append(
         (re.compile(r'(\<|\b)' + _template + r'\s*\<'),
          _template + '<>',
          _header))
 
 
 def FilesBelongToSameModule(filename_cc, filename_h):
@@ skipping 106 matching lines @@
 
     # String is special -- it is a non-templatized type in STL.
     matched = _RE_PATTERN_STRING.search(line)
     if matched:
       # Don't warn about strings in non-STL namespaces:
       # (We check only the first match per line; good enough.)
       prefix = line[:matched.start()]
       if prefix.endswith('std::') or not prefix.endswith('::'):
         required['<string>'] = (linenum, 'string')
 
-    for pattern, template, header in _re_pattern_algorithm_header:
+    for pattern, template, header in _RE_PATTERN_HEADERS_MAYBE_TEMPLATES:
       if pattern.search(line):
         required[header] = (linenum, template)
 
     # The following function is just a speed up, no semantics are changed.
     if not '<' in line:  # Reduces the cpu time usage by skipping lines.
       continue
 
     for pattern, template, header in _re_pattern_templates:
       if pattern.search(line):
         required[header] = (linenum, template)
@@ skipping 377 matching lines @@
     CheckForHeaderGuard(filename, clean_lines, error)
 
   for line in xrange(clean_lines.NumLines()):
     ProcessLine(filename, file_extension, clean_lines, line,
                 include_state, function_state, nesting_state, error,
                 extra_check_functions)
     FlagCxx11Features(filename, clean_lines, line, error)
   nesting_state.CheckCompletedBlocks(filename, error)
 
   CheckForIncludeWhatYouUse(filename, clean_lines, include_state, error)
-  
+
   # Check that the .cc file has included its header if it exists.
   if file_extension == 'cc':
     CheckHeaderFileIncluded(filename, include_state, error)
 
   # We check here rather than inside ProcessLine so that we see raw
   # lines rather than "cleaned" lines.
   CheckForBadCharacters(filename, lines, error)
 
   CheckForNewlineAtEOF(filename, lines, error)
 
@@ skipping 266 matching lines @@
   _cpplint_state.ResetErrorCounts()
   for filename in filenames:
     ProcessFile(filename, _cpplint_state.verbose_level)
   _cpplint_state.PrintErrorCounts()
 
   sys.exit(_cpplint_state.error_count > 0)
 
 
 if __name__ == '__main__':
   main()