68 lines
2.2 KiB
C++
68 lines
2.2 KiB
C++
/*
|
||
* Copyright (c) 2022, Linus Groh <linusg@serenityos.org>
|
||
* Copyright (c) 2022, networkException <networkexception@serenityos.org>
|
||
*
|
||
* SPDX-License-Identifier: BSD-2-Clause
|
||
*/
|
||
|
||
#include <AK/String.h>
|
||
#include <AK/Utf16View.h>
|
||
#include <AK/Utf8View.h>
|
||
#include <LibWeb/Infra/CharacterTypes.h>
|
||
#include <LibWeb/Infra/Strings.h>
|
||
|
||
namespace Web::Infra {
|
||
|
||
// https://infra.spec.whatwg.org/#strip-and-collapse-ascii-whitespace
|
||
String strip_and_collapse_whitespace(StringView string)
|
||
{
|
||
// Replace any sequence of one or more consecutive code points that are ASCII whitespace in the string with a single U+0020 SPACE code point.
|
||
StringBuilder builder;
|
||
for (auto code_point : Utf8View { string }) {
|
||
if (Infra::is_ascii_whitespace(code_point)) {
|
||
if (!builder.string_view().ends_with(' '))
|
||
builder.append(' ');
|
||
continue;
|
||
}
|
||
builder.append_code_point(code_point);
|
||
}
|
||
|
||
// ...and then remove any leading and trailing ASCII whitespace from that string.
|
||
return builder.string_view().trim(Infra::ASCII_WHITESPACE);
|
||
}
|
||
|
||
// https://infra.spec.whatwg.org/#code-unit-prefix
|
||
bool is_code_unit_prefix(StringView potential_prefix, StringView input)
|
||
{
|
||
auto potential_prefix_utf16 = utf8_to_utf16(potential_prefix);
|
||
auto input_utf16 = utf8_to_utf16(input);
|
||
|
||
// 1. Let i be 0.
|
||
size_t i = 0;
|
||
|
||
// 2. While true:
|
||
while (true) {
|
||
// 1. If i is greater than or equal to potentialPrefix’s length, then return true.
|
||
if (i >= potential_prefix.length())
|
||
return true;
|
||
|
||
// 2. If i is greater than or equal to input’s length, then return false.
|
||
if (i >= input.length())
|
||
return false;
|
||
|
||
// 3. Let potentialPrefixCodeUnit be the ith code unit of potentialPrefix.
|
||
auto potential_prefix_code_unit = Utf16View(potential_prefix_utf16).code_unit_at(i);
|
||
|
||
// 4. Let inputCodeUnit be the ith code unit of input.
|
||
auto input_code_unit = Utf16View(input_utf16).code_unit_at(i);
|
||
|
||
// 5. Return false if potentialPrefixCodeUnit is not inputCodeUnit.
|
||
if (potential_prefix_code_unit != input_code_unit)
|
||
return false;
|
||
|
||
// 6. Set i to i + 1.
|
||
++i;
|
||
}
|
||
}
|
||
|
||
}
|