skia2/tests/VptrTest.cpp
Mike Klein 0554d497f8 add SkVptr()
I was wondering how feasible using this to make downcasts safe would be.
These tests would need to build and pass on all our bots, at least.

Change-Id: I1753ba58841bf6c17d6ac3af7374518356e1bb05
Reviewed-on: https://skia-review.googlesource.com/81180
Reviewed-by: Brian Salomon <bsalomon@google.com>
Commit-Queue: Mike Klein <mtklein@chromium.org>
2017-12-06 19:37:27 +00:00

62 lines
1.6 KiB
C++

/*
* Copyright 2017 Google Inc.
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#include "SkMakeUnique.h"
#include "SkVptr.h"
#include "Test.h"
namespace {
struct Base {
virtual ~Base() = default;
virtual size_t val() const = 0;
};
struct SubclassA : public Base {
SubclassA(size_t val) : fVal(val) {}
size_t val() const override { return fVal; }
size_t fVal;
};
struct SubclassB : public Base {
SubclassB() {}
size_t val() const override { return 42; }
};
}
DEF_TEST(Vptr, r) {
std::unique_ptr<Base> a = skstd::make_unique<SubclassA>(21),
b = skstd::make_unique<SubclassB>(),
c = skstd::make_unique<SubclassA>(22),
d = skstd::make_unique<SubclassB>();
// These 4 objects all have unique identities.
REPORTER_ASSERT(r, a != b);
REPORTER_ASSERT(r, a != c);
REPORTER_ASSERT(r, a != d);
REPORTER_ASSERT(r, b != c);
REPORTER_ASSERT(r, b != d);
REPORTER_ASSERT(r, c != d);
// Only b and d have the same val().
REPORTER_ASSERT(r, a->val() != b->val());
REPORTER_ASSERT(r, a->val() != c->val());
REPORTER_ASSERT(r, a->val() != d->val());
REPORTER_ASSERT(r, b->val() != c->val());
REPORTER_ASSERT(r, b->val() == d->val());
REPORTER_ASSERT(r, c->val() != d->val());
// SkVptr() returns the same value for objects of the same concrete type.
REPORTER_ASSERT(r, SkVptr(*a) == SkVptr(*c));
REPORTER_ASSERT(r, SkVptr(*b) == SkVptr(*d));
REPORTER_ASSERT(r, SkVptr(*a) != SkVptr(*b));
}