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// Copyright 2020 Dolphin Emulator Project
// SPDX-License-Identifier: GPL-2.0-or-later
#pragma once
#include <cstddef>
#include <string_view>
namespace Common
{
constexpr std::size_t CountFmtReplacementFields(std::string_view s)
{
std::size_t count = 0;
for (std::size_t i = 0; i < s.size(); ++i)
{
if (s[i] != '{')
continue;
// If the opening brace is followed by another brace, what we have is
// an escaped brace, not a replacement field.
if (i + 1 < s.size() && s[i + 1] == '{')
{
// Skip the second brace.
// This ensures that e.g. {{{}}} is counted correctly: when the first brace character
// is read and detected as being part of an '{{' escape sequence, the second character
// is skipped so the most inner brace (the third character) is not detected
// as the end of an '{{' pair.
++i;
continue;
}
++count;
}
return count;
}
static_assert(CountFmtReplacementFields("") == 0);
static_assert(CountFmtReplacementFields("{} test {:x}") == 2);
static_assert(CountFmtReplacementFields("{} {{}} test {{{}}}") == 2);
constexpr bool ContainsNonPositionalArguments(std::string_view s)
{
for (std::size_t i = 0; i < s.size(); ++i)
{
if (s[i] != '{' || i + 1 == s.size())
continue;
const char next = s[i + 1];
// If the opening brace is followed by another brace, what we have is
// an escaped brace, not a replacement field.
if (next == '{')
{
// Skip the second brace.
// This ensures that e.g. {{{}}} is counted correctly: when the first brace character
// is read and detected as being part of an '{{' escape sequence, the second character
// is skipped so the most inner brace (the third character) is not detected
// as the end of an '{{' pair.
++i;
}
else if (next == '}' || next == ':')
{
return true;
}
}
return false;
}
static_assert(!ContainsNonPositionalArguments(""));
static_assert(ContainsNonPositionalArguments("{}"));
static_assert(!ContainsNonPositionalArguments("{0}"));
static_assert(ContainsNonPositionalArguments("{:x}"));
static_assert(!ContainsNonPositionalArguments("{0:x}"));
static_assert(!ContainsNonPositionalArguments("{0} {{}} test {{{1}}}"));
} // namespace Common
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