Re-implement parse.

* Work with const CharT* format at the lowest level.
* Avoid dependence on std::lib except for locale-sensitive parsing.
* Add tests for parse.

test/date_test/parse.pass.cpp

@@ -0,0 +1,730 @@
+// The MIT License (MIT)
+//
+// Copyright (c) 2016 Howard Hinnant
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in all
+// copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+// SOFTWARE.
+
+// This test is meant to maintain a record of the sizeof each type.
+
+#include "date.h"
+#include <cassert>
+#include <sstream>
+
+void
+test_a()
+{
+    using namespace date;
+    {
+        // correct abbreviation
+        std::istringstream in{"Sun 2016-12-11"};
+        sys_days tp;
+        parse(in, "%a %F", tp);
+        assert(!in.fail());
+        assert(!in.bad());
+        assert(!in.eof());
+        assert(tp == 2016_y/12/11);
+    }
+    {
+        // correct abbreviation
+        std::istringstream in{"Sun 2016-12-11"};
+        sys_days tp;
+        parse(in, "%A %F", tp);
+        assert(!in.fail());
+        assert(!in.bad());
+        assert(!in.eof());
+        assert(tp == 2016_y/12/11);
+    }
+    {
+        // correct full name
+        std::istringstream in{"Sunday 2016-12-11"};
+        sys_days tp;
+        parse(in, "%a %F", tp);
+        assert(!in.fail());
+        assert(!in.bad());
+        assert(!in.eof());
+        assert(tp == 2016_y/12/11);
+    }
+    {
+        // correct full name
+        std::istringstream in{"Sunday 2016-12-11"};
+        sys_days tp;
+        parse(in, "%A %F", tp);
+        assert(!in.fail());
+        assert(!in.bad());
+        assert(!in.eof());
+        assert(tp == 2016_y/12/11);
+    }
+    {
+        // not a valid name
+        std::istringstream in{"Dec 2016-12-11"};
+        sys_days tp;
+        parse(in, "%a %F", tp);
+        assert( in.fail());
+        assert(!in.bad());
+        assert(!in.eof());
+        assert(tp == 1970_y/1/1);
+    }
+    {
+        // wrong name
+        std::istringstream in{"Sat 2016-12-11"};
+        sys_days tp;
+        parse(in, "%a %F", tp);
+        assert( in.fail());
+        assert(!in.bad());
+        assert(!in.eof());
+        assert(tp == 1970_y/1/1);
+    }
+    {
+        // extra ws in input
+        std::istringstream in{"Sun  2016-12-11"};
+        sys_days tp;
+        parse(in, "%a %F", tp);
+        assert(!in.fail());
+        assert(!in.bad());
+        assert(!in.eof());
+        assert(tp == 2016_y/12/11);
+    }
+    {
+        // extra ws in format
+        std::istringstream in{"Sun 2016-12-11"};
+        sys_days tp;
+        parse(in, "%a  %F", tp);
+        assert(!in.fail());
+        assert(!in.bad());
+        assert(!in.eof());
+        assert(tp == 2016_y/12/11);
+    }
+}
+
+void
+test_b()
+{
+    using namespace date;
+    {
+        // correct abbreviation
+        std::istringstream in{"Dec 11 2016"};
+        sys_days tp;
+        parse(in, "%b %d %Y", tp);
+        assert(!in.fail());
+        assert(!in.bad());
+        assert(!in.eof());
+        assert(tp == 2016_y/12/11);
+    }
+    {
+        // correct abbreviation
+        std::istringstream in{"Dec 11 2016"};
+        sys_days tp;
+        parse(in, "%B %d %Y", tp);
+        assert(!in.fail());
+        assert(!in.bad());
+        assert(!in.eof());
+        assert(tp == 2016_y/12/11);
+    }
+    {
+        // correct abbreviation
+        std::istringstream in{"Dec 11 2016"};
+        sys_days tp;
+        parse(in, "%h %d %Y", tp);
+        assert(!in.fail());
+        assert(!in.bad());
+        assert(!in.eof());
+        assert(tp == 2016_y/12/11);
+    }
+    {
+        // correct full name
+        std::istringstream in{"December 11 2016"};
+        sys_days tp;
+        parse(in, "%b %d %Y", tp);
+        assert(!in.fail());
+        assert(!in.bad());
+        assert(!in.eof());
+        assert(tp == 2016_y/12/11);
+    }
+    {
+        // correct full name
+        std::istringstream in{"December 11 2016"};
+        sys_days tp;
+        parse(in, "%B %d %Y", tp);
+        assert(!in.fail());
+        assert(!in.bad());
+        assert(!in.eof());
+        assert(tp == 2016_y/12/11);
+    }
+    {
+        // correct full name
+        std::istringstream in{"December 11 2016"};
+        sys_days tp;
+        parse(in, "%h %d %Y", tp);
+        assert(!in.fail());
+        assert(!in.bad());
+        assert(!in.eof());
+        assert(tp == 2016_y/12/11);
+    }
+    {
+        // incorrect abbreviation
+        std::istringstream in{"Dece 11 2016"};
+        sys_days tp;
+        parse(in, "%b %d %Y", tp);
+        assert( in.fail());
+        assert(!in.bad());
+        assert(!in.eof());
+        assert(tp == 1970_y/1/1);
+    }
+}
+
+void
+test_c()
+{
+    using namespace date;
+    using namespace std::chrono;
+    {
+        // correct abbreviation
+        std::istringstream in{"Sun Dec 11 14:02:43 2016"};
+        sys_seconds tp;
+        parse(in, "%c", tp);
+        assert(!in.fail());
+        assert(!in.bad());
+        assert(tp == sys_days{2016_y/12/11} + hours{14} + minutes{2} + seconds{43});
+    }
+}
+
+void
+test_x()
+{
+    using namespace date;
+    using namespace std::chrono;
+    {
+        // correct abbreviation
+        std::istringstream in{"12/11/16"};
+        sys_seconds tp;
+        parse(in, "%x", tp);
+        assert(!in.fail());
+        assert(!in.bad());
+        assert(tp == sys_days{2016_y/12/11});
+    }
+}
+
+void
+test_X()
+{
+    using namespace date;
+    using namespace std::chrono;
+    {
+        // correct abbreviation
+        std::istringstream in{"2016-12-11 14:02:43"};
+        sys_seconds tp;
+        parse(in, "%F %X", tp);
+        assert(!in.fail());
+        assert(!in.bad());
+        assert(tp == sys_days{2016_y/12/11} + hours{14} + minutes{2} + seconds{43});
+    }
+}
+
+void
+test_C()
+{
+    using namespace date;
+    using namespace std::chrono;
+    {
+        std::istringstream in{"20 16 12 11"};
+        sys_days tp;
+        parse(in, "%C %y %m %d", tp);
+        assert(!in.fail());
+        assert(!in.bad());
+        assert(tp == 2016_y/12/11);
+    }
+    {
+        std::istringstream in{"-2 1 12 11"};
+        sys_days tp;
+        parse(in, "%C %y %m %d", tp);
+        assert(!in.fail());
+        assert(!in.bad());
+        assert(tp == -101_y/12/11);
+    }
+    {
+        std::istringstream in{"-1 0 12 11"};
+        sys_days tp;
+        parse(in, "%C %y %m %d", tp);
+        assert(!in.fail());
+        assert(!in.bad());
+        assert(tp == -100_y/12/11);
+    }
+    {
+        std::istringstream in{"-1 99 12 11"};
+        sys_days tp;
+        parse(in, "%C %y %m %d", tp);
+        assert(!in.fail());
+        assert(!in.bad());
+        assert(tp == -99_y/12/11);
+    }
+    {
+        std::istringstream in{"-1 1 12 11"};
+        sys_days tp;
+        parse(in, "%C %y %m %d", tp);
+        assert(!in.fail());
+        assert(!in.bad());
+        assert(tp == -1_y/12/11);
+    }
+    {
+        std::istringstream in{"0 0 12 11"};
+        sys_days tp;
+        parse(in, "%C %y %m %d", tp);
+        assert(!in.fail());
+        assert(!in.bad());
+        assert(tp == 0_y/12/11);
+    }
+    {
+        std::istringstream in{"0 1 12 11"};
+        sys_days tp;
+        parse(in, "%C %y %m %d", tp);
+        assert(!in.fail());
+        assert(!in.bad());
+        assert(tp == 1_y/12/11);
+    }
+    {
+        std::istringstream in{"0 99 12 11"};
+        sys_days tp;
+        parse(in, "%C %y %m %d", tp);
+        assert(!in.fail());
+        assert(!in.bad());
+        assert(tp == 99_y/12/11);
+    }
+    {
+        std::istringstream in{"1 0 12 11"};
+        sys_days tp;
+        parse(in, "%C %y %m %d", tp);
+        assert(!in.fail());
+        assert(!in.bad());
+        assert(tp == 100_y/12/11);
+    }
+    {
+        std::istringstream in{"1 1 12 11"};
+        sys_days tp;
+        parse(in, "%C %y %m %d", tp);
+        assert(!in.fail());
+        assert(!in.bad());
+        assert(tp == 101_y/12/11);
+    }
+}
+
+void
+test_d()
+{
+    using namespace date;
+    using namespace std::chrono;
+    {
+        std::istringstream in{"2016 09 12"};
+        sys_days tp;
+        parse(in, "%Y %d %m", tp);
+        assert(!in.fail());
+        assert(!in.bad());
+        assert(tp == 2016_y/12/9);
+    }
+    {
+        std::istringstream in{"2016 09 12"};
+        sys_days tp;
+        parse(in, "%Y %e %m", tp);
+        assert(!in.fail());
+        assert(!in.bad());
+        assert(tp == 2016_y/12/9);
+    }
+    {
+        std::istringstream in{"2016 9 12"};
+        sys_days tp;
+        parse(in, "%Y %d %m", tp);
+        assert(!in.fail());
+        assert(!in.bad());
+        assert(tp == 2016_y/12/9);
+    }
+    {
+        std::istringstream in{"2016 9 12"};
+        sys_days tp;
+        parse(in, "%Y %e %m", tp);
+        assert(!in.fail());
+        assert(!in.bad());
+        assert(tp == 2016_y/12/9);
+    }
+}
+
+void
+test_D()
+{
+    using namespace date;
+    using namespace std::chrono;
+    {
+        std::istringstream in{"12/11/16"};
+        sys_days tp;
+        parse(in, "%D", tp);
+        assert(!in.fail());
+        assert(!in.bad());
+        assert(tp == 2016_y/12/11);
+    }
+}
+
+void
+test_F()
+{
+    using namespace date;
+    using namespace std::chrono;
+    {
+        std::istringstream in{"2016-12-13"};
+        sys_days tp;
+        parse(in, "%F", tp);
+        assert(!in.fail());
+        assert(!in.bad());
+        assert(tp == 2016_y/12/13);
+    }
+}
+
+void
+test_H()
+{
+    using namespace date;
+    using namespace std::chrono;
+    {
+        std::istringstream in{"2016-12-11 15"};
+        sys_time<hours> tp;
+        parse(in, "%F %H", tp);
+        assert(!in.fail());
+        assert(!in.bad());
+        assert(tp == sys_days{2016_y/12/11} + hours{15});
+    }
+}
+
+void
+test_Ip()
+{
+    using namespace date;
+    using namespace std::chrono;
+    {
+        std::istringstream in{"2016-12-11 1 pm"};
+        sys_time<hours> tp;
+        parse(in, "%F %I %p", tp);
+        assert(!in.fail());
+        assert(!in.bad());
+        assert(tp == sys_days{2016_y/12/11} + hours{13});
+    }
+    {
+        std::istringstream in{"2016-12-11 1 am"};
+        sys_time<hours> tp;
+        parse(in, "%F %I %p", tp);
+        assert(!in.fail());
+        assert(!in.bad());
+        assert(tp == sys_days{2016_y/12/11} + hours{1});
+    }
+}
+
+void
+test_j()
+{
+    using namespace date;
+    using namespace std::chrono;
+    {
+        std::istringstream in{"2016 361"};
+        sys_days tp;
+        parse(in, "%Y %j", tp);
+        assert(!in.fail());
+        assert(!in.bad());
+        assert(tp == sys_days{2016_y/12/26});
+    }
+}
+
+void
+test_m()
+{
+    using namespace date;
+    using namespace std::chrono;
+    {
+        std::istringstream in{"2016 12 09"};
+        sys_days tp;
+        parse(in, "%Y %d %m", tp);
+        assert(!in.fail());
+        assert(!in.bad());
+        assert(tp == 2016_y/9/12);
+    }
+    {
+        std::istringstream in{"2016 12 9"};
+        sys_days tp;
+        parse(in, "%Y %d %m", tp);
+        assert(!in.fail());
+        assert(!in.bad());
+        assert(tp == 2016_y/9/12);
+    }
+}
+
+void
+test_M()
+{
+    using namespace date;
+    using namespace std::chrono;
+    {
+        std::istringstream in{"2016-12-11 15"};
+        sys_time<minutes> tp;
+        parse(in, "%F %M", tp);
+        assert(!in.fail());
+        assert(!in.bad());
+        assert(tp == sys_days{2016_y/12/11} + minutes{15});
+    }
+}
+
+void
+test_S()
+{
+    using namespace date;
+    using namespace std::chrono;
+    {
+        std::istringstream in{"2016-12-11 15"};
+        sys_seconds tp;
+        parse(in, "%F %S", tp);
+        assert(!in.fail());
+        assert(!in.bad());
+        assert(tp == sys_days{2016_y/12/11} + seconds{15});
+    }
+    {
+        std::istringstream in{"2016-12-11 15.001"};
+        sys_time<milliseconds> tp;
+        parse(in, "%F %S", tp);
+        assert(!in.fail());
+        assert(!in.bad());
+        assert(tp == sys_days{2016_y/12/11} + seconds{15} + milliseconds{1});
+    }
+}
+
+void
+test_T()
+{
+    using namespace date;
+    using namespace std::chrono;
+    {
+        std::istringstream in{"2016-12-11 15:43:22"};
+        sys_seconds tp;
+        parse(in, "%F %T", tp);
+        assert(!in.fail());
+        assert(!in.bad());
+        assert(tp == sys_days{2016_y/12/11} + hours{15} + minutes{43} + seconds{22});
+    }
+    {
+        std::istringstream in{"2016-12-11 15:43:22.001"};
+        sys_time<milliseconds> tp;
+        parse(in, "%F %T", tp);
+        assert(!in.fail());
+        assert(!in.bad());
+        assert(tp == sys_days{2016_y/12/11} + hours{15} + minutes{43} + seconds{22} +
+                                              milliseconds{1});
+    }
+    {
+        std::istringstream in{"2016-12-11 15:43:22"};
+        sys_time<milliseconds> tp;
+        parse(in, "%F %T", tp);
+        assert(!in.fail());
+        assert(!in.bad());
+        assert(tp == sys_days{2016_y/12/11} + hours{15} + minutes{43} + seconds{22});
+    }
+}
+
+void
+test_p()
+{
+    using namespace date;
+    using namespace std::chrono;
+    {
+        std::istringstream in{"2016-12-11 11pm"};
+        sys_time<hours> tp;
+        parse(in, "%F %I%p", tp);
+        assert(!in.fail());
+        assert(!in.bad());
+        assert(tp == sys_days{2016_y/12/11} + hours{23});
+    }
+}
+
+void
+test_r()
+{
+    using namespace date;
+    using namespace std::chrono;
+    {
+        std::istringstream in{"2016-12-26 1:36:57 pm"};
+        sys_seconds tp;
+        parse(in, "%F %r", tp);
+        assert(!in.fail());
+        assert(!in.bad());
+        assert(tp == sys_days{2016_y/12/26} + hours{13} + minutes{36} + seconds{57});
+    }
+}
+
+void
+test_R()
+{
+    using namespace date;
+    using namespace std::chrono;
+    {
+        std::istringstream in{"2016-12-26 13:36"};
+        sys_seconds tp;
+        parse(in, "%F %R", tp);
+        assert(!in.fail());
+        assert(!in.bad());
+        assert(tp == sys_days{2016_y/12/26} + hours{13} + minutes{36});
+    }
+}
+
+void
+test_U()
+{
+    using namespace date;
+    using namespace std::chrono;
+    {
+        std::istringstream in{"2016-52-1"};
+        sys_days tp;
+        parse(in, "%Y-%U-%w", tp);
+        assert(!in.fail());
+        assert(!in.bad());
+        assert(tp == sys_days{2016_y/12/26});
+    }
+}
+
+void
+test_W()
+{
+    using namespace date;
+    using namespace std::chrono;
+    {
+        std::istringstream in{"2016-52-1"};
+        sys_days tp;
+        parse(in, "%Y-%W-%w", tp);
+        assert(!in.fail());
+        assert(!in.bad());
+        assert(tp == sys_days{2016_y/12/26});
+    }
+}
+
+void
+test_GV()
+{
+    using namespace date;
+    using namespace std::chrono;
+    {
+        std::istringstream in{"2016-52-1"};
+        sys_days tp;
+        parse(in, "%G-%V-%w", tp);
+        assert(!in.fail());
+        assert(!in.bad());
+        assert(tp == sys_days{2016_y/12/26});
+    }
+    {
+        std::istringstream in{"2016-52-1"};
+        sys_days tp;
+        parse(in, "%G-%V-%w", tp);
+        assert(!in.fail());
+        assert(!in.bad());
+        assert(tp == sys_days{2016_y/12/26});
+    }
+    {
+        std::istringstream in{"20 16-52-1"};
+        sys_days tp;
+        parse(in, "%C %g-%V-%w", tp);
+        assert(!in.fail());
+        assert(!in.bad());
+        assert(tp == sys_days{2016_y/12/26});
+    }
+    {
+        std::istringstream in{"20 16-52-1"};
+        sys_days tp;
+        parse(in, "%C %g-%V-%u", tp);
+        assert(!in.fail());
+        assert(!in.bad());
+        assert(tp == sys_days{2016_y/12/26});
+    }
+}
+
+void
+test_z()
+{
+    using namespace date;
+    using namespace std::chrono;
+    {
+        std::istringstream in{"2016-12-26 15:53:22 -0500"};
+        sys_seconds tp;
+        parse(in, "%F %T %z", tp);
+        assert(!in.fail());
+        assert(!in.bad());
+        assert(tp == sys_days{2016_y/12/26} + hours{20} + minutes{53} + seconds{22});
+    }
+    {
+        std::istringstream in{"2016-12-26 15:53:22 -0500"};
+        local_seconds tp;
+        parse(in, "%F %T %z", tp);
+        assert(!in.fail());
+        assert(!in.bad());
+        assert(tp == local_days{2016_y/12/26} + hours{15} + minutes{53} + seconds{22});
+    }
+    {
+        std::istringstream in{"2016-12-26 15:53:22 -05:00"};
+        sys_seconds tp;
+        parse(in, "%F %T %Ez", tp);
+        assert(!in.fail());
+        assert(!in.bad());
+        assert(tp == sys_days{2016_y/12/26} + hours{20} + minutes{53} + seconds{22});
+    }
+}
+
+void
+test_Z()
+{
+    using namespace date;
+    using namespace std::chrono;
+    {
+        std::string a;
+        std::istringstream in{"2016-12-26 15:53:22 word"};
+        local_seconds tp;
+        parse(in, "%F %T %Z", tp, a);
+        assert(!in.fail());
+        assert(!in.bad());
+        assert(tp == local_days{2016_y/12/26} + hours{15} + minutes{53} + seconds{22});
+        assert(a == "word");
+    }
+}
+
+int
+main()
+{
+    test_a();
+    test_b();
+    test_c();
+    test_C();
+    test_d();
+    test_D();
+    test_F();
+    test_H();
+    test_Ip();
+    test_j();
+    test_m();
+    test_M();
+    test_p();
+    test_r();
+    test_R();
+    test_S();
+    test_T();
+    test_U();
+    test_W();
+    test_GV();
+    test_x();
+    test_X();
+    test_z();
+    test_Z();
+}