skia2/tests/FunctionTest.cpp
mtklein 0d992db1cf Make SkFunction copyable so it can go in containers.
This totally overhauls the implementation to use ordinary inheritance-based type erasure.  I give up for now getting my manual vtable shenanigans to work with MSVC.  Still those same "expected ; before ), also expected ) before ;" errors.

I added support for uninitialized SkFunctions and operator=(), because it was fairly straightforward with this implementation.

The main downside here is that I've removed the inline implementation.  All SkFunctions involve a heap allocation, even when just wrapping function pointers.

BUG=skia:

Review URL: https://codereview.chromium.org/1056673002
2015-05-06 07:40:26 -07:00

71 lines
2.2 KiB
C++

/*
* Copyright 2015 Google Inc.
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#include "SkFunction.h"
#include "Test.h"
static void test_add_five(skiatest::Reporter* r, SkFunction<int(int)>& f) {
REPORTER_ASSERT(r, f(3) == 8);
REPORTER_ASSERT(r, f(4) == 9);
}
static void test_add_five(skiatest::Reporter* r, SkFunction<int(int)>&& f) { test_add_five(r, f); }
static int add_five(int x) { return x + 5; }
struct AddFive {
int operator()(int x) const { return x + 5; };
};
class MoveOnlyThree : SkNoncopyable {
public:
MoveOnlyThree() {}
MoveOnlyThree(MoveOnlyThree&&) {}
MoveOnlyThree& operator=(MoveOnlyThree&&) { return *this; }
int val() { return 3; }
};
DEF_TEST(Function, r) {
// We should be able to turn a function pointer, an explicit functor, or a
// lambda into an SkFunction all equally well.
test_add_five(r, &add_five);
test_add_five(r, AddFive());
test_add_five(r, [](int x) { return x + 5; });
// AddFive and the lambda above are both small enough to test small-object optimization.
// Now test a lambda that's much too large for the small-object optimization.
int a = 1, b = 1, c = 1, d = 1, e = 1;
test_add_five(r, [&](int x) { return x + a + b + c + d + e; });
// Makes sure we forward arguments when calling SkFunction.
SkFunction<int(int, MoveOnlyThree&&, int)> f([](int x, MoveOnlyThree&& three, int y) {
return x * three.val() + y;
});
REPORTER_ASSERT(r, f(2, MoveOnlyThree(), 4) == 10);
// SkFunctions can go in containers.
SkTArray<SkFunction<int(int)>> add_fivers;
add_fivers.push_back(&add_five);
add_fivers.push_back(AddFive());
add_fivers.push_back([](int x) { return x + 5; });
add_fivers.push_back([&](int x) { return x + a + b + c + d + e; });
for (auto& f : add_fivers) {
test_add_five(r, f);
}
// SkFunctions are assignable.
SkFunction<int(int)> empty;
empty = [](int x) { return x + 5; };
test_add_five(r, empty);
// This all is silly acrobatics, but it should at least work correctly.
SkFunction<int(int)> emptyA, emptyB(emptyA);
emptyA = emptyB;
emptyA = emptyA;
}