v8/test/unittests/base/iterator-unittest.cc
Philip Pfaffe c51c9f7ca9 Improve iterator_range to take non-&& arguments
The current implementation takes forwarding reference arguments, which
is fine when you call it with rvalues, like
make_iterator_range(V.begin(), V.end()). If you call it with lvalues
though, it doesn't do what you'd expect. ForwardIterator becomes a
reference:

Foo I = V.begin();
make_iterator_range(I, I); //ForwardIterator is deduced as Foo&

Since iterator are supposed to be small, no harm in passing them by
value.

Change-Id: I151c87304949d810c72c42f60e9d1a7151f61f83
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2020780
Commit-Queue: Philip Pfaffe <pfaffe@chromium.org>
Reviewed-by: Clemens Backes <clemensb@chromium.org>
Cr-Commit-Position: refs/heads/master@{#66007}
2020-01-28 13:03:43 +00:00

73 lines
2.0 KiB
C++

// Copyright 2014 the V8 project authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "src/base/iterator.h"
#include <deque>
#include "test/unittests/test-utils.h"
namespace v8 {
namespace base {
TEST(IteratorTest, IteratorRangeEmpty) {
base::iterator_range<char*> r;
EXPECT_EQ(r.begin(), r.end());
EXPECT_EQ(r.end(), r.cend());
EXPECT_EQ(r.begin(), r.cbegin());
EXPECT_TRUE(r.empty());
EXPECT_EQ(0, r.size());
}
TEST(IteratorTest, IteratorRangeArray) {
int array[10] = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9};
base::iterator_range<int*> r1(&array[0], &array[10]);
for (auto i : r1) {
EXPECT_EQ(array[i], i);
}
EXPECT_EQ(10, r1.size());
EXPECT_FALSE(r1.empty());
for (size_t i = 0; i < arraysize(array); ++i) {
EXPECT_EQ(r1[i], array[i]);
}
base::iterator_range<int*> r2(&array[0], &array[0]);
EXPECT_EQ(0, r2.size());
EXPECT_TRUE(r2.empty());
for (auto i : array) {
EXPECT_EQ(r2.end(), std::find(r2.begin(), r2.end(), i));
}
}
TEST(IteratorTest, IteratorRangeDeque) {
using C = std::deque<int>;
C c;
c.push_back(1);
c.push_back(2);
c.push_back(2);
base::iterator_range<typename C::iterator> r(c.begin(), c.end());
EXPECT_EQ(3, r.size());
EXPECT_FALSE(r.empty());
EXPECT_TRUE(c.begin() == r.begin());
EXPECT_TRUE(c.end() == r.end());
EXPECT_EQ(0, std::count(r.begin(), r.end(), 0));
EXPECT_EQ(1, std::count(r.begin(), r.end(), 1));
EXPECT_EQ(2, std::count(r.begin(), r.end(), 2));
}
TEST(IteratorTest, IteratorTypeDeduction) {
base::iterator_range<char*> r;
auto r2 = make_iterator_range(r.begin(), r.end());
EXPECT_EQ(r2.begin(), r.begin());
EXPECT_EQ(r2.end(), r2.end());
auto I = r.begin(), E = r.end();
// Check that this compiles and does the correct thing even if the iterators
// are lvalues:
auto r3 = make_iterator_range(I, E);
EXPECT_TRUE((std::is_same<decltype(r2), decltype(r3)>::value));
EXPECT_EQ(r3.begin(), r.begin());
EXPECT_EQ(r3.end(), r2.end());
}
} // namespace base
} // namespace v8