gcc/c-family/c-spellcheck.cc

   1 /* Find near-matches for macros.
   2    Copyright (C) 2016-2017 Free Software Foundation, Inc.
   3
   4 This file is part of GCC.
   5
   6 GCC is free software; you can redistribute it and/or modify it under
   7 the terms of the GNU General Public License as published by the Free
   8 Software Foundation; either version 3, or (at your option) any later
   9 version.
  10
  11 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
  12 WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14 for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with GCC; see the file COPYING3.  If not see
  18 <http://www.gnu.org/licenses/>.  */
  19
  20 #include "config.h"
  21 #include "system.h"
  22 #include "coretypes.h"
  23 #include "tm.h"
  24 #include "tree.h"
  25 #include "cpplib.h"
  26 #include "spellcheck-tree.h"
  27 #include "c-family/c-spellcheck.h"
  28 #include "selftest.h"
  29
  30 /* Return true iff STR begin with an underscore and either an uppercase
  31    letter or another underscore, and is thus, for C and C++, reserved for
  32    use by the implementation.  */
  33
  34 bool
  35 name_reserved_for_implementation_p (const char *str)
  36 {
  37   if (str[0] != '_')
  38     return false;
  39   return (str[1] == '_' || ISUPPER(str[1]));
  40 }
  41
  42 /* Return true iff HASHNODE is a macro that should be offered as a
  43    suggestion for a misspelling.  */
  44
  45 static bool
  46 should_suggest_as_macro_p (cpp_hashnode *hashnode)
  47 {
  48   if (hashnode->type != NT_MACRO)
  49     return false;
  50
  51   /* Don't suggest names reserved for the implementation, but do suggest the builtin
  52      macros such as __FILE__, __LINE__ etc.  */
  53   if (name_reserved_for_implementation_p ((const char *)hashnode->ident.str)
  54       && !(hashnode->flags & NODE_BUILTIN))
  55     return false;
  56
  57   return true;
  58 }
  59
  60 /* A callback for cpp_forall_identifiers, for use by best_macro_match's ctor.
  61    Process HASHNODE and update the best_macro_match instance pointed to be
  62    USER_DATA.  */
  63
  64 static int
  65 find_closest_macro_cpp_cb (cpp_reader *, cpp_hashnode *hashnode,
  66                            void *user_data)
  67 {
  68   if (!should_suggest_as_macro_p (hashnode))
  69     return 1;
  70
  71   best_macro_match *bmm = (best_macro_match *)user_data;
  72   bmm->consider (hashnode);
  73
  74   /* Keep iterating.  */
  75   return 1;
  76 }
  77
  78 /* Constructor for best_macro_match.
  79    Use find_closest_macro_cpp_cb to find the closest matching macro to
  80    NAME within distance < best_distance_so_far. */
  81
  82 best_macro_match::best_macro_match (tree goal,
  83                                     edit_distance_t best_distance_so_far,
  84                                     cpp_reader *reader)
  85 : best_match <goal_t, candidate_t> (goal, best_distance_so_far)
  86 {
  87   cpp_forall_identifiers (reader, find_closest_macro_cpp_cb, this);
  88 }
  89
  90 #if CHECKING_P
  91
  92 namespace selftest {
  93
  94 /* Selftests.  */
  95
  96 /* Verify that name_reserved_for_implementation_p is sane.  */
  97
  98 static void
  99 test_name_reserved_for_implementation_p ()
 100 {
 101   ASSERT_FALSE (name_reserved_for_implementation_p (""));
 102   ASSERT_FALSE (name_reserved_for_implementation_p ("foo"));
 103   ASSERT_FALSE (name_reserved_for_implementation_p ("_"));
 104   ASSERT_FALSE (name_reserved_for_implementation_p ("_foo"));
 105   ASSERT_FALSE (name_reserved_for_implementation_p ("_42"));
 106   ASSERT_TRUE (name_reserved_for_implementation_p ("_Foo"));
 107   ASSERT_TRUE (name_reserved_for_implementation_p ("__"));
 108   ASSERT_TRUE (name_reserved_for_implementation_p ("__foo"));
 109 }
 110
 111 /* Run all of the selftests within this file.  */
 112
 113 void
 114 c_spellcheck_cc_tests ()
 115 {
 116   test_name_reserved_for_implementation_p ();
 117 }
 118
 119 } // namespace selftest
 120
 121 #endif /* #if CHECKING_P */