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/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#ifndef intl_components_gtest_TestBuffer_h_
#define intl_components_gtest_TestBuffer_h_
#include <string_view>
#include "mozilla/DebugOnly.h"
#include "mozilla/Utf8.h"
#include "mozilla/Vector.h"
namespace mozilla::intl {
/**
* A test buffer for interfacing with unified intl classes.
* Closely resembles the FormatBuffer class, but without
* JavaScript-specific implementation details.
*/
template <typename C, size_t inlineCapacity = 0>
class TestBuffer {
public:
using CharType = C;
// Only allow moves, and not copies, as this class owns the mozilla::Vector.
TestBuffer(TestBuffer&& other) noexcept = default;
TestBuffer& operator=(TestBuffer&& other) noexcept = default;
explicit TestBuffer(const size_t aSize = 0) { reserve(aSize); }
/**
* Ensures the buffer has enough space to accommodate |aSize| elemtns.
*/
bool reserve(const size_t aSize) { return mBuffer.reserve(aSize); }
/**
* Returns the raw data inside the buffer.
*/
CharType* data() { return mBuffer.begin(); }
/**
* Returns the count of elements in written to the buffer.
*/
size_t length() const { return mBuffer.length(); }
/**
* Returns the buffer's overall capacity.
*/
size_t capacity() const { return mBuffer.capacity(); }
/**
* Resizes the buffer to the given amount of written elements.
* This is necessary because the buffer gets written to across
* FFI boundaries, so this needs to happen in a separate step.
*/
void written(size_t aAmount) {
MOZ_ASSERT(aAmount <= mBuffer.capacity());
mozilla::DebugOnly<bool> result = mBuffer.resizeUninitialized(aAmount);
MOZ_ASSERT(result);
}
/**
* Get a string view into the buffer, which is useful for test assertions.
*/
std::basic_string_view<CharType> get_string_view() {
return std::basic_string_view<CharType>(data(), length());
}
/**
* Clear the buffer, allowing it to be re-used.
*/
void clear() { mBuffer.clear(); }
/**
* A utility function to convert UTF-16 strings to UTF-8 strings so that they
* can be logged to stderr.
*/
static std::string toUtf8(mozilla::Span<const char16_t> input) {
size_t buff_len = input.Length() * 3;
std::string result(buff_len, ' ');
result.reserve(buff_len);
size_t result_len =
ConvertUtf16toUtf8(input, mozilla::Span(result.data(), buff_len));
result.resize(result_len);
return result;
}
/**
* String buffers, especially UTF-16, do not assert nicely, and are difficult
* to debug. This function is verbose in that it prints the buffer contents
* and expected contents to stderr when they do not match.
*
* Usage:
* ASSERT_TRUE(buffer.assertStringView(u"9/23/2002, 8:07:30 PM"));
*
* Here is what gtests output:
*
* Expected equality of these values:
* buffer.get_string_view()
* Which is: { '0' (48, 0x30), '9' (57, 0x39), '/' (47, 0x2F), ... }
* "9/23/2002, 8:07:30 PM"
* Which is: 0x11600afb9
*
* Here is what this method outputs:
*
* The buffer did not match:
* Buffer:
* u"9/23/2002, 8:07:30 PM"
* Expected:
* u"09/23/2002, 08:07:30 PM"
*/
[[nodiscard]] bool verboseMatches(const CharType* aExpected) {
std::basic_string_view<CharType> actualSV(data(), length());
std::basic_string_view<CharType> expectedSV(aExpected);
if (actualSV.compare(expectedSV) == 0) {
return true;
}
static_assert(std::is_same_v<CharType, char> ||
std::is_same_v<CharType, char16_t>);
std::string actual;
std::string expected;
const char* startQuote;
if constexpr (std::is_same_v<CharType, char>) {
actual = std::string(actualSV);
expected = std::string(expectedSV);
startQuote = "\"";
}
if constexpr (std::is_same_v<CharType, char16_t>) {
actual = toUtf8(actualSV);
expected = toUtf8(expectedSV);
startQuote = "u\"";
}
fprintf(stderr, "The buffer did not match:\n");
fprintf(stderr, " Buffer:\n %s%s\"\n", startQuote, actual.c_str());
fprintf(stderr, " Expected:\n %s%s\"\n", startQuote, expected.c_str());
return false;
}
Vector<C, inlineCapacity> mBuffer{};
};
} // namespace mozilla::intl
#endif