libstdc++-v3/testsuite/20_util/variant/run.cc

   1 // { dg-options "-std=gnu++17" }
   2 // { dg-do run }
   3
   4 // Copyright (C) 2016-2018 Free Software Foundation, Inc.
   5 //
   6 // This file is part of the GNU ISO C++ Library.  This library is free
   7 // software; you can redistribute it and/or modify it under the
   8 // terms of the GNU General Public License as published by the
   9 // Free Software Foundation; either version 3, or (at your option)
  10 // any later version.
  11
  12 // This library is distributed in the hope that it will be useful,
  13 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 // GNU General Public License for more details.
  16
  17 // You should have received a copy of the GNU General Public License along
  18 // with this library; see the file COPYING3.  If not see
  19 // <http://www.gnu.org/licenses/>.
  20
  21 #include <variant>
  22 #include <string>
  23 #include <vector>
  24 #include <unordered_set>
  25 #include <testsuite_hooks.h>
  26
  27 using namespace std;
  28
  29 struct AlwaysThrow
  30 {
  31   AlwaysThrow() = default;
  32
  33   AlwaysThrow(const AlwaysThrow&)
  34   { throw nullptr; }
  35
  36   AlwaysThrow(AlwaysThrow&&)
  37   { throw nullptr; }
  38
  39   AlwaysThrow& operator=(const AlwaysThrow&)
  40   {
  41     throw nullptr;
  42     return *this;
  43   }
  44
  45   AlwaysThrow& operator=(AlwaysThrow&&)
  46   {
  47     throw nullptr;
  48     return *this;
  49   }
  50
  51   bool operator<(const AlwaysThrow&) const { VERIFY(false); }
  52   bool operator<=(const AlwaysThrow&) const { VERIFY(false); }
  53   bool operator==(const AlwaysThrow&) const { VERIFY(false); }
  54   bool operator!=(const AlwaysThrow&) const { VERIFY(false); }
  55   bool operator>=(const AlwaysThrow&) const { VERIFY(false); }
  56   bool operator>(const AlwaysThrow&) const { VERIFY(false); }
  57 };
  58
  59 void default_ctor()
  60 {
  61   variant<monostate, string> v;
  62   VERIFY(holds_alternative<monostate>(v));
  63 }
  64
  65 void copy_ctor()
  66 {
  67   variant<monostate, string> v("a");
  68   VERIFY(holds_alternative<string>(v));
  69   variant<monostate, string> u(v);
  70   VERIFY(holds_alternative<string>(u));
  71   VERIFY(get<string>(u) == "a");
  72 }
  73
  74 void move_ctor()
  75 {
  76   variant<monostate, string> v("a");
  77   VERIFY(holds_alternative<string>(v));
  78   variant<monostate, string> u(std::move(v));
  79   VERIFY(holds_alternative<string>(u));
  80   VERIFY(get<string>(u) == "a");
  81   VERIFY(holds_alternative<string>(v));
  82 }
  83
  84 void arbitrary_ctor()
  85 {
  86   variant<int, string> v("a");
  87   VERIFY(holds_alternative<string>(v));
  88   VERIFY(get<1>(v) == "a");
  89 }
  90
  91 void copy_assign()
  92 {
  93   variant<monostate, string> v("a");
  94   VERIFY(holds_alternative<string>(v));
  95   variant<monostate, string> u;
  96   u = v;
  97   VERIFY(holds_alternative<string>(u));
  98   VERIFY(get<string>(u) == "a");
  99 }
 100
 101 void move_assign()
 102 {
 103   variant<monostate, string> v("a");
 104   VERIFY(holds_alternative<string>(v));
 105   variant<monostate, string> u;
 106   u = std::move(v);
 107   VERIFY(holds_alternative<string>(u));
 108   VERIFY(get<string>(u) == "a");
 109   VERIFY(holds_alternative<string>(v));
 110 }
 111
 112 void arbitrary_assign()
 113 {
 114   variant<int, string> v;
 115   v = "a";
 116
 117   VERIFY(holds_alternative<string>(variant<int, string>("a")));
 118   VERIFY(get<1>(v) == "a");
 119 }
 120
 121 void dtor()
 122 {
 123   struct A {
 124       A(int& called) : called(called) {}
 125       ~A() {
 126           called++;
 127       }
 128       int& called;
 129   };
 130   {
 131     int called = 0;
 132     { variant<string, A> a(in_place_index<1>, called); }
 133     VERIFY(called == 1);
 134   }
 135   {
 136     int called = 0;
 137     { variant<string, A> a(in_place_index<0>); }
 138     VERIFY(called == 0);
 139   }
 140 }
 141
 142 void in_place_index_ctor()
 143 {
 144   {
 145     variant<int, string> v(in_place_index<1>, "a");
 146     VERIFY(holds_alternative<string>(v));
 147     VERIFY(get<1>(v) == "a");
 148   }
 149   {
 150     variant<int, string> v(in_place_index<1>, {'a', 'b'});
 151     VERIFY(holds_alternative<string>(v));
 152     VERIFY(get<1>(v) == "ab");
 153   }
 154 }
 155
 156 void in_place_type_ctor()
 157 {
 158   {
 159     variant<int, string> v(in_place_type<string>, "a");
 160     VERIFY(holds_alternative<string>(v));
 161     VERIFY(get<1>(v) == "a");
 162   }
 163   {
 164     variant<int, string> v(in_place_type<string>, {'a', 'b'});
 165     VERIFY(holds_alternative<string>(v));
 166     VERIFY(get<1>(v) == "ab");
 167   }
 168 }
 169
 170 void emplace()
 171 {
 172   variant<int, string> v;
 173   v.emplace<0>(1);
 174   VERIFY(get<0>(v) == 1);
 175   v.emplace<string>("a");
 176   VERIFY(get<string>(v) == "a");
 177   v.emplace<1>({'a', 'b'});
 178   VERIFY(get<1>(v) == "ab");
 179   v.emplace<string>({'a', 'c'});
 180   VERIFY(get<string>(v) == "ac");
 181   {
 182     variant<int, AlwaysThrow> v;
 183     AlwaysThrow a;
 184     try { v.emplace<1>(a); } catch (nullptr_t) { }
 185     VERIFY(v.valueless_by_exception());
 186   }
 187   {
 188     variant<int, AlwaysThrow> v;
 189     try { v.emplace<1>(AlwaysThrow{}); } catch (nullptr_t) { }
 190     VERIFY(v.valueless_by_exception());
 191   }
 192   VERIFY(&v.emplace<0>(1) == &std::get<0>(v));
 193   VERIFY(&v.emplace<int>(1) == &std::get<int>(v));
 194   VERIFY(&v.emplace<1>("a") == &std::get<1>(v));
 195   VERIFY(&v.emplace<string>("a") == &std::get<string>(v));
 196   {
 197     variant<vector<int>> v;
 198     VERIFY(&v.emplace<0>({1,2,3}) == &std::get<0>(v));
 199     VERIFY(&v.emplace<vector<int>>({1,2,3}) == &std::get<vector<int>>(v));
 200   }
 201 }
 202
 203 void test_get()
 204 {
 205   VERIFY(get<1>(variant<int, string>("a")) == "a");
 206   VERIFY(get<string>(variant<int, string>("a")) == "a");
 207   {
 208     bool caught = false;
 209
 210     try
 211       {
 212         get<0>(variant<int, string>("a"));
 213       }
 214     catch (const bad_variant_access&)
 215       {
 216         caught = true;
 217       }
 218     VERIFY(caught);
 219   }
 220   {
 221     bool caught = false;
 222
 223     try
 224       {
 225         get<int>(variant<int, string>("a"));
 226       }
 227     catch (const bad_variant_access&)
 228       {
 229         caught = true;
 230       }
 231     VERIFY(caught);
 232   }
 233 }
 234
 235 void test_relational()
 236 {
 237   VERIFY((variant<int, string>(2) < variant<int, string>(3)));
 238   VERIFY((variant<int, string>(3) == variant<int, string>(3)));
 239   VERIFY((variant<int, string>(3) > variant<int, string>(2)));
 240   VERIFY((variant<int, string>(3) <= variant<int, string>(3)));
 241   VERIFY((variant<int, string>(2) <= variant<int, string>(3)));
 242   VERIFY((variant<int, string>(3) >= variant<int, string>(3)));
 243   VERIFY((variant<int, string>(3) >= variant<int, string>(2)));
 244   VERIFY((variant<int, string>(2) != variant<int, string>(3)));
 245
 246   VERIFY((variant<int, string>(2) < variant<int, string>("a")));
 247   VERIFY((variant<string, int>(2) > variant<string, int>("a")));
 248
 249   {
 250     variant<int, AlwaysThrow> v, w;
 251     try
 252       {
 253         AlwaysThrow a;
 254         v = a;
 255       }
 256     catch (nullptr_t) { }
 257     VERIFY(v.valueless_by_exception());
 258     VERIFY(v < w);
 259     VERIFY(v <= w);
 260     VERIFY(!(v == w));
 261     VERIFY(v != w);
 262     VERIFY(w > v);
 263     VERIFY(w >= v);
 264   }
 265 }
 266
 267 void test_swap()
 268 {
 269   variant<int, string> a("a"), b("b");
 270   a.swap(b);
 271   VERIFY(get<1>(a) == "b");
 272   VERIFY(get<1>(b) == "a");
 273   swap(a, b);
 274   VERIFY(get<1>(a) == "a");
 275   VERIFY(get<1>(b) == "b");
 276 }
 277
 278 void test_visit()
 279 {
 280   {
 281     struct Visitor
 282     {
 283       int operator()(int, float) {
 284           return 0;
 285       }
 286       int operator()(int, double) {
 287           return 1;
 288       }
 289       int operator()(char, float) {
 290           return 2;
 291       }
 292       int operator()(char, double) {
 293           return 3;
 294       }
 295       int operator()(int, float) const {
 296           return 5;
 297       }
 298       int operator()(int, double) const {
 299           return 6;
 300       }
 301       int operator()(char, float) const {
 302           return 7;
 303       }
 304       int operator()(char, double) const {
 305           return 8;
 306       }
 307     } visitor1;
 308     VERIFY(visit(visitor1, variant<int, char>(1), variant<float, double>(1.0f)) == 0);
 309     VERIFY(visit(visitor1, variant<int, char>(1), variant<float, double>(1.0)) == 1);
 310     VERIFY(visit(visitor1, variant<int, char>('a'), variant<float, double>(1.0f)) == 2);
 311     VERIFY(visit(visitor1, variant<int, char>('a'), variant<float, double>(1.0)) == 3);
 312
 313     const auto& visitor2 = visitor1;
 314     VERIFY(visit(visitor2, variant<int, char>(1), variant<float, double>(1.0f)) == 5);
 315     VERIFY(visit(visitor2, variant<int, char>(1), variant<float, double>(1.0)) == 6);
 316     VERIFY(visit(visitor2, variant<int, char>('a'), variant<float, double>(1.0f)) == 7);
 317     VERIFY(visit(visitor2, variant<int, char>('a'), variant<float, double>(1.0)) == 8);
 318   }
 319
 320   {
 321     struct Visitor
 322     {
 323       int operator()(int, float) && {
 324           return 0;
 325       }
 326       int operator()(int, double) && {
 327           return 1;
 328       }
 329       int operator()(char, float) && {
 330           return 2;
 331       }
 332       int operator()(char, double) && {
 333           return 3;
 334       }
 335     };
 336     VERIFY(visit(Visitor{}, variant<int, char>(1), variant<float, double>(1.0f)) == 0);
 337     VERIFY(visit(Visitor{}, variant<int, char>(1), variant<float, double>(1.0)) == 1);
 338     VERIFY(visit(Visitor{}, variant<int, char>('a'), variant<float, double>(1.0f)) == 2);
 339     VERIFY(visit(Visitor{}, variant<int, char>('a'), variant<float, double>(1.0)) == 3);
 340   }
 341 }
 342
 343 void test_hash()
 344 {
 345   unordered_set<variant<int, string>> s;
 346   VERIFY(s.emplace(3).second);
 347   VERIFY(s.emplace("asdf").second);
 348   VERIFY(s.emplace().second);
 349   VERIFY(s.size() == 3);
 350   VERIFY(!s.emplace(3).second);
 351   VERIFY(!s.emplace("asdf").second);
 352   VERIFY(!s.emplace().second);
 353   VERIFY(s.size() == 3);
 354   {
 355     struct A
 356     {
 357       operator int()
 358       {
 359         throw nullptr;
 360       }
 361     };
 362     variant<int, string> v;
 363     try
 364       {
 365         v.emplace<0>(A{});
 366       }
 367     catch (nullptr_t)
 368       {
 369       }
 370     VERIFY(v.valueless_by_exception());
 371     VERIFY(s.insert(v).second);
 372     VERIFY(s.size() == 4);
 373     VERIFY(!s.insert(v).second);
 374   }
 375 }
 376
 377 void test_valueless_by_exception()
 378 {
 379   {
 380     AlwaysThrow a;
 381     bool caught = false;
 382     try
 383       {
 384         variant<int, AlwaysThrow> v(a);
 385       }
 386     catch (nullptr_t)
 387       {
 388         caught = true;
 389       }
 390     VERIFY(caught);
 391   }
 392   {
 393     AlwaysThrow a;
 394     bool caught = false;
 395     try
 396       {
 397         variant<int, AlwaysThrow> v(a);
 398       }
 399     catch (nullptr_t)
 400       {
 401         caught = true;
 402       }
 403     VERIFY(caught);
 404   }
 405   {
 406     variant<int, AlwaysThrow> v;
 407     bool caught = false;
 408     try
 409       {
 410         AlwaysThrow a;
 411         v = a;
 412       }
 413     catch (nullptr_t)
 414       {
 415         caught = true;
 416       }
 417     VERIFY(caught);
 418     VERIFY(v.valueless_by_exception());
 419   }
 420   {
 421     variant<int, AlwaysThrow> v;
 422     bool caught = false;
 423     try
 424       {
 425         v = AlwaysThrow{};
 426       }
 427     catch (nullptr_t)
 428       {
 429         caught = true;
 430       }
 431     VERIFY(caught);
 432     VERIFY(v.valueless_by_exception());
 433   }
 434 }
 435
 436 int main()
 437 {
 438   default_ctor();
 439   copy_ctor();
 440   move_ctor();
 441   arbitrary_ctor();
 442   in_place_index_ctor();
 443   in_place_type_ctor();
 444   copy_assign();
 445   move_assign();
 446   arbitrary_assign();
 447   dtor();
 448   emplace();
 449   test_get();
 450   test_relational();
 451   test_swap();
 452   test_visit();
 453   test_hash();
 454   test_valueless_by_exception();
 455 }