ceph/src/boost/libs/spirit/test/x3/omit.cpp

   1 /*=============================================================================
   2     Copyright (c) 2001-2015 Joel de Guzman
   3
   4     Distributed under the Boost Software License, Version 1.0. (See accompanying
   5     file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
   6 =============================================================================*/
   7 #include <boost/detail/lightweight_test.hpp>
   8 #include <boost/spirit/home/x3.hpp>
   9 #include <boost/fusion/include/vector.hpp>
  10 #include <boost/fusion/include/at.hpp>
  11
  12 #include <string>
  13 #include <iostream>
  14 #include "test.hpp"
  15
  16 int
  17 main()
  18 {
  19     using namespace boost::spirit::x3::ascii;
  20     using boost::spirit::x3::omit;
  21     using boost::spirit::x3::unused_type;
  22     using boost::spirit::x3::unused;
  23     using boost::spirit::x3::int_;
  24
  25     using boost::fusion::vector;
  26     using boost::fusion::at_c;
  27
  28     using spirit_test::test;
  29     using spirit_test::test_attr;
  30
  31     BOOST_SPIRIT_ASSERT_CONSTEXPR_CTORS(omit['x']);
  32
  33     {
  34         BOOST_TEST(test("a", omit['a']));
  35     }
  36
  37     {
  38         // omit[] means we don't receive the attribute
  39         char attr;
  40         BOOST_TEST((test_attr("abc", omit[char_] >> omit['b'] >> char_, attr)));
  41         BOOST_TEST((attr == 'c'));
  42     }
  43
  44     {
  45         // If all elements except 1 is omitted, the attribute is
  46         // a single-element sequence. For this case alone, we allow
  47         // naked attributes (unwrapped in a fusion sequence).
  48         char attr;
  49         BOOST_TEST((test_attr("abc", omit[char_] >> 'b' >> char_, attr)));
  50         BOOST_TEST((attr == 'c'));
  51     }
  52
  53     {
  54         // omit[] means we don't receive the attribute
  55         vector<> attr;
  56         BOOST_TEST((test_attr("abc", omit[char_] >> omit['b'] >> omit[char_], attr)));
  57     }
  58
  59     {
  60         // omit[] means we don't receive the attribute
  61         // this test is merely a compile test, because using a unused as the
  62         // explicit attribute doesn't make any sense
  63         unused_type attr;
  64         BOOST_TEST((test_attr("abc", omit[char_ >> 'b' >> char_], attr)));
  65     }
  66
  67     {
  68         // omit[] means we don't receive the attribute, if all elements of a
  69         // sequence have unused attributes, the whole sequence has an unused
  70         // attribute as well
  71         vector<char, char> attr;
  72         BOOST_TEST((test_attr("abcde",
  73             char_ >> (omit[char_] >> omit['c'] >> omit[char_]) >> char_, attr)));
  74         BOOST_TEST((at_c<0>(attr) == 'a'));
  75         BOOST_TEST((at_c<1>(attr) == 'e'));
  76     }
  77
  78     {
  79         // "hello" has an unused_type. unused attrubutes are not part of the sequence
  80         vector<char, char> attr;
  81         BOOST_TEST((test_attr("a hello c", char_ >> "hello" >> char_, attr, space)));
  82         BOOST_TEST((at_c<0>(attr) == 'a'));
  83         BOOST_TEST((at_c<1>(attr) == 'c'));
  84     }
  85
  86     {
  87         // if only one node in a sequence is left (all the others are omitted),
  88         // then we need "naked" attributes (not wrapped in a tuple)
  89         int attr;
  90         BOOST_TEST((test_attr("a 123 c", omit['a'] >> int_ >> omit['c'], attr, space)));
  91         BOOST_TEST((attr == 123));
  92     }
  93
  94     {
  95         // unused means we don't care about the attribute
  96         BOOST_TEST((test_attr("abc", char_ >> 'b' >> char_, unused)));
  97     }
  98
  99     {   // test action with omitted attribute
 100         char c = 0;
 101         auto f = [&](auto& ctx){ c = _attr(ctx); };
 102
 103         BOOST_TEST(test("x123\"a string\"", (char_ >> omit[int_] >> "\"a string\"")[f]));
 104         BOOST_TEST(c == 'x');
 105     }
 106
 107     {   // test action with omitted attribute
 108         int n = 0;
 109         auto f = [&](auto& ctx){ n = _attr(ctx); };
 110
 111         BOOST_TEST(test("x 123 \"a string\"", (omit[char_] >> int_ >> "\"a string\"")[f], space));
 112         BOOST_TEST(n == 123);
 113     }
 114
 115     return boost::report_errors();
 116 }