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
main()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     {
32         BOOST_TEST(test("a", omit['a']));
33     }
34 
35     {
36         // omit[] means we don't receive the attribute
37         char attr;
38         BOOST_TEST((test_attr("abc", omit[char_] >> omit['b'] >> char_, attr)));
39         BOOST_TEST((attr == 'c'));
40     }
41 
42     {
43         // If all elements except 1 is omitted, the attribute is
44         // a single-element sequence. For this case alone, we allow
45         // naked attributes (unwrapped in a fusion sequence).
46         char attr;
47         BOOST_TEST((test_attr("abc", omit[char_] >> 'b' >> char_, attr)));
48         BOOST_TEST((attr == 'c'));
49     }
50 
51     {
52         // omit[] means we don't receive the attribute
53         vector<> attr;
54         BOOST_TEST((test_attr("abc", omit[char_] >> omit['b'] >> omit[char_], attr)));
55     }
56 
57     {
58         // omit[] means we don't receive the attribute
59         // this test is merely a compile test, because using a unused as the
60         // explicit attribute doesn't make any sense
61         unused_type attr;
62         BOOST_TEST((test_attr("abc", omit[char_ >> 'b' >> char_], attr)));
63     }
64 
65     {
66         // omit[] means we don't receive the attribute, if all elements of a
67         // sequence have unused attributes, the whole sequence has an unused
68         // attribute as well
69         vector<char, char> attr;
70         BOOST_TEST((test_attr("abcde",
71             char_ >> (omit[char_] >> omit['c'] >> omit[char_]) >> char_, attr)));
72         BOOST_TEST((at_c<0>(attr) == 'a'));
73         BOOST_TEST((at_c<1>(attr) == 'e'));
74     }
75 
76     {
77         // "hello" has an unused_type. unused attrubutes are not part of the sequence
78         vector<char, char> attr;
79         BOOST_TEST((test_attr("a hello c", char_ >> "hello" >> char_, attr, space)));
80         BOOST_TEST((at_c<0>(attr) == 'a'));
81         BOOST_TEST((at_c<1>(attr) == 'c'));
82     }
83 
84     {
85         // if only one node in a sequence is left (all the others are omitted),
86         // then we need "naked" attributes (not wraped in a tuple)
87         int attr;
88         BOOST_TEST((test_attr("a 123 c", omit['a'] >> int_ >> omit['c'], attr, space)));
89         BOOST_TEST((attr == 123));
90     }
91 
92     {
93         // unused means we don't care about the attribute
94         BOOST_TEST((test_attr("abc", char_ >> 'b' >> char_, unused)));
95     }
96 
97     {   // test action with omitted attribute
98         char c = 0;
99         auto f = [&](auto& ctx){ c = _attr(ctx); };
100 
101         BOOST_TEST(test("x123\"a string\"", (char_ >> omit[int_] >> "\"a string\"")[f]));
102         BOOST_TEST(c == 'x');
103     }
104 
105     {   // test action with omitted attribute
106         int n = 0;
107         auto f = [&](auto& ctx){ n = _attr(ctx); };
108 
109         BOOST_TEST(test("x 123 \"a string\"", (omit[char_] >> int_ >> "\"a string\"")[f], space));
110         BOOST_TEST(n == 123);
111     }
112 
113     return boost::report_errors();
114 }
115