skia2/tests/TArrayTest.cpp
John Stiles 31954bf23f Enable ClangTidy check performance-unnecessary-copy-initialization.
https://clang.llvm.org/extra/clang-tidy/checks/performance-unnecessary-copy-initialization.html

Finds local variable declarations that are initialized using the copy
constructor of a non-trivially-copyable type but it would suffice to
obtain a const reference.

The check is only applied if it is safe to replace the copy by a const
reference. This is the case when the variable is const qualified or when
it is only used as a const, i.e. only const methods or operators are
invoked on it, or it is used as const reference or value argument in
constructors or function calls.

Change-Id: I1261410deccd8ea64e85edec53fbd5360940e587
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/308759
Commit-Queue: John Stiles <johnstiles@google.com>
Reviewed-by: Mike Klein <mtklein@google.com>
2020-08-07 22:20:36 +00:00

257 lines
7.9 KiB
C++

/*
* Copyright 2014 Google Inc.
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#include "include/core/SkRefCnt.h"
#include "include/private/SkTArray.h"
#include "include/utils/SkRandom.h"
#include "tests/Test.h"
// Tests the SkTArray<T> class template.
template <bool MEM_MOVE>
static void TestTSet_basic(skiatest::Reporter* reporter) {
SkTArray<int, MEM_MOVE> a;
// Starts empty.
REPORTER_ASSERT(reporter, a.empty());
REPORTER_ASSERT(reporter, a.count() == 0);
// { }, add a default constructed element
a.push_back() = 0;
REPORTER_ASSERT(reporter, !a.empty());
REPORTER_ASSERT(reporter, a.count() == 1);
// { 0 }, removeShuffle the only element.
a.removeShuffle(0);
REPORTER_ASSERT(reporter, a.empty());
REPORTER_ASSERT(reporter, a.count() == 0);
// { }, add a default, add a 1, remove first
a.push_back() = 0;
REPORTER_ASSERT(reporter, a.push_back() = 1);
a.removeShuffle(0);
REPORTER_ASSERT(reporter, !a.empty());
REPORTER_ASSERT(reporter, a.count() == 1);
REPORTER_ASSERT(reporter, a[0] == 1);
// { 1 }, replace with new array
int b[5] = { 0, 1, 2, 3, 4 };
a.reset(b, SK_ARRAY_COUNT(b));
REPORTER_ASSERT(reporter, a.count() == SK_ARRAY_COUNT(b));
REPORTER_ASSERT(reporter, a[2] == 2);
REPORTER_ASSERT(reporter, a[4] == 4);
// { 0, 1, 2, 3, 4 }, removeShuffle the last
a.removeShuffle(4);
REPORTER_ASSERT(reporter, a.count() == SK_ARRAY_COUNT(b) - 1);
REPORTER_ASSERT(reporter, a[3] == 3);
// { 0, 1, 2, 3 }, remove a middle, note shuffle
a.removeShuffle(1);
REPORTER_ASSERT(reporter, a.count() == SK_ARRAY_COUNT(b) - 2);
REPORTER_ASSERT(reporter, a[0] == 0);
REPORTER_ASSERT(reporter, a[1] == 3);
REPORTER_ASSERT(reporter, a[2] == 2);
// {0, 3, 2 }
}
template <typename T> static void test_swap(skiatest::Reporter* reporter,
SkTArray<T>* (&arrays)[4],
int (&sizes)[7])
{
for (auto a : arrays) {
for (auto b : arrays) {
if (a == b) {
continue;
}
for (auto sizeA : sizes) {
for (auto sizeB : sizes) {
a->reset();
b->reset();
int curr = 0;
for (int i = 0; i < sizeA; i++) { a->push_back(curr++); }
for (int i = 0; i < sizeB; i++) { b->push_back(curr++); }
a->swap(*b);
REPORTER_ASSERT(reporter, b->count() == sizeA);
REPORTER_ASSERT(reporter, a->count() == sizeB);
curr = 0;
for (auto&& x : *b) { REPORTER_ASSERT(reporter, x == curr++); }
for (auto&& x : *a) { REPORTER_ASSERT(reporter, x == curr++); }
a->swap(*a);
curr = sizeA;
for (auto&& x : *a) { REPORTER_ASSERT(reporter, x == curr++); }
}}
}}
}
static void test_swap(skiatest::Reporter* reporter) {
int sizes[] = {0, 1, 5, 10, 15, 20, 25};
SkTArray<int> arr;
SkSTArray< 5, int> arr5;
SkSTArray<10, int> arr10;
SkSTArray<20, int> arr20;
SkTArray<int>* arrays[] = { &arr, &arr5, &arr10, &arr20 };
test_swap(reporter, arrays, sizes);
struct MoveOnlyInt {
MoveOnlyInt(int i) : fInt(i) {}
MoveOnlyInt(MoveOnlyInt&& that) : fInt(that.fInt) {}
bool operator==(int i) { return fInt == i; }
int fInt;
};
SkTArray<MoveOnlyInt> moi;
SkSTArray< 5, MoveOnlyInt> moi5;
SkSTArray<10, MoveOnlyInt> moi10;
SkSTArray<20, MoveOnlyInt> moi20;
SkTArray<MoveOnlyInt>* arraysMoi[] = { &moi, &moi5, &moi10, &moi20 };
test_swap(reporter, arraysMoi, sizes);
}
template <typename T, bool MEM_MOVE> int SkTArray<T, MEM_MOVE>::allocCntForTest() const {
return fAllocCount;
}
void test_unnecessary_alloc(skiatest::Reporter* reporter) {
{
SkTArray<int> a;
REPORTER_ASSERT(reporter, a.allocCntForTest() == 0);
}
{
SkSTArray<10, int> a;
REPORTER_ASSERT(reporter, a.allocCntForTest() == 10);
}
{
SkTArray<int> a(1);
REPORTER_ASSERT(reporter, a.allocCntForTest() >= 1);
}
{
SkTArray<int> a, b;
b = a;
REPORTER_ASSERT(reporter, b.allocCntForTest() == 0);
}
{
SkSTArray<10, int> a;
SkTArray<int> b;
b = a;
REPORTER_ASSERT(reporter, b.allocCntForTest() == 0);
}
{
SkTArray<int> a;
SkTArray<int> b(a); // NOLINT(performance-unnecessary-copy-initialization)
REPORTER_ASSERT(reporter, b.allocCntForTest() == 0);
}
{
SkSTArray<10, int> a;
SkTArray<int> b(a); // NOLINT(performance-unnecessary-copy-initialization)
REPORTER_ASSERT(reporter, b.allocCntForTest() == 0);
}
{
SkTArray<int> a;
SkTArray<int> b(std::move(a));
REPORTER_ASSERT(reporter, b.allocCntForTest() == 0);
}
{
SkSTArray<10, int> a;
SkTArray<int> b(std::move(a));
REPORTER_ASSERT(reporter, b.allocCntForTest() == 0);
}
{
SkTArray<int> a;
SkTArray<int> b;
b = std::move(a);
REPORTER_ASSERT(reporter, b.allocCntForTest() == 0);
}
{
SkSTArray<10, int> a;
SkTArray<int> b;
b = std::move(a);
REPORTER_ASSERT(reporter, b.allocCntForTest() == 0);
}
}
static void test_self_assignment(skiatest::Reporter* reporter) {
SkTArray<int> a;
a.push_back(1);
REPORTER_ASSERT(reporter, !a.empty());
REPORTER_ASSERT(reporter, a.count() == 1);
REPORTER_ASSERT(reporter, a[0] == 1);
a = static_cast<decltype(a)&>(a);
REPORTER_ASSERT(reporter, !a.empty());
REPORTER_ASSERT(reporter, a.count() == 1);
REPORTER_ASSERT(reporter, a[0] == 1);
}
template <typename Array> static void test_array_reserve(skiatest::Reporter* reporter,
Array* array, int reserveCount) {
SkRandom random;
REPORTER_ASSERT(reporter, array->allocCntForTest() >= reserveCount);
array->push_back();
REPORTER_ASSERT(reporter, array->allocCntForTest() >= reserveCount);
array->pop_back();
REPORTER_ASSERT(reporter, array->allocCntForTest() >= reserveCount);
while (array->count() < reserveCount) {
// Two steps forward, one step back
if (random.nextULessThan(3) < 2) {
array->push_back();
} else if (array->count() > 0) {
array->pop_back();
}
REPORTER_ASSERT(reporter, array->allocCntForTest() >= reserveCount);
}
}
template<typename Array> static void test_reserve(skiatest::Reporter* reporter) {
// Test that our allocated space stays >= to the reserve count until the array is filled to
// the reserve count
for (int reserveCount : {1, 2, 10, 100}) {
// Test setting reserve in constructor.
Array array1(reserveCount);
test_array_reserve(reporter, &array1, reserveCount);
// Test setting reserve after constructor.
Array array2;
array2.reserve(reserveCount);
test_array_reserve(reporter, &array2, reserveCount);
// Test increasing reserve after constructor.
Array array3(reserveCount/2);
array3.reserve(reserveCount);
test_array_reserve(reporter, &array3, reserveCount);
// Test setting reserve on non-empty array.
Array array4;
array4.push_back_n(reserveCount);
array4.reserve(reserveCount);
array4.pop_back_n(reserveCount);
test_array_reserve(reporter, &array4, 2 * reserveCount);
}
}
DEF_TEST(TArray, reporter) {
TestTSet_basic<true>(reporter);
TestTSet_basic<false>(reporter);
test_swap(reporter);
test_unnecessary_alloc(reporter);
test_self_assignment(reporter);
test_reserve<SkTArray<int>>(reporter);
test_reserve<SkSTArray<1, int>>(reporter);
test_reserve<SkSTArray<2, int>>(reporter);
test_reserve<SkSTArray<16, int>>(reporter);
}