gdb/unittests/scoped_restore-selftests.c

   1 /* Self tests for scoped_restore for GDB, the GNU debugger.
   2
   3    Copyright (C) 2017-2024 Free Software Foundation, Inc.
   4
   5    This file is part of GDB.
   6
   7    This program is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 3 of the License, or
  10    (at your option) any later version.
  11
  12    This program 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
  18    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  19
  20 #include "gdbsupport/selftest.h"
  21 #include "gdbsupport/scoped_restore.h"
  22
  23 namespace selftests {
  24 namespace scoped_restore_tests {
  25
  26 struct Base {};
  27 struct Derived : Base {};
  28
  29 static int global;
  30
  31 /* Check that we can return a scoped_restore from a function.  Below
  32    we'll make sure this does the right thing.  */
  33 static scoped_restore_tmpl<int>
  34 make_scoped_restore_global (int value)
  35 {
  36   return make_scoped_restore (&global, value);
  37 }
  38
  39 static void
  40 run_tests ()
  41 {
  42   /* Test that single-argument make_scoped_restore restores the
  43      original value on scope exit.  */
  44   {
  45     int integer = 0;
  46     {
  47       scoped_restore restore = make_scoped_restore (&integer);
  48       SELF_CHECK (integer == 0);
  49       integer = 1;
  50     }
  51     SELF_CHECK (integer == 0);
  52   }
  53
  54   /* Same, with two-argument make_scoped_restore.  */
  55   {
  56     int integer = 0;
  57     {
  58       scoped_restore restore = make_scoped_restore (&integer, 1);
  59       SELF_CHECK (integer == 1);
  60     }
  61     SELF_CHECK (integer == 0);
  62   }
  63
  64   /* Test releasing a scoped_restore.  */
  65   {
  66     int integer = 0;
  67     {
  68       scoped_restore restore = make_scoped_restore (&integer, 1);
  69       SELF_CHECK (integer == 1);
  70       restore.release ();
  71     }
  72     /* The overridden value should persist.  */
  73     SELF_CHECK (integer == 1);
  74   }
  75
  76   /* Test creating a scoped_restore with a value of a type convertible
  77      to T.  */
  78   {
  79     Base *base = nullptr;
  80     Derived derived;
  81     {
  82       scoped_restore restore = make_scoped_restore (&base, &derived);
  83
  84       SELF_CHECK (base == &derived);
  85     }
  86     SELF_CHECK (base == nullptr);
  87   }
  88
  89   /* Test calling a function that returns a scoped restore.  Makes
  90      sure that if the compiler emits a call to the copy ctor, that we
  91      still do the right thing.  */
  92   {
  93     {
  94       SELF_CHECK (global == 0);
  95       scoped_restore restore = make_scoped_restore_global (1);
  96       SELF_CHECK (global == 1);
  97     }
  98     SELF_CHECK (global == 0);
  99   }
 100 }
 101
 102 } /* namespace scoped_restore_tests */
 103 } /* namespace selftests */
 104
 105 void _initialize_scoped_restore_selftests ();
 106 void
 107 _initialize_scoped_restore_selftests ()
 108 {
 109   selftests::register_test ("scoped_restore",
 110                             selftests::scoped_restore_tests::run_tests);
 111 }