catch2/include/internal/catch_approx.cpp
Martin Hořeňovský 84fa76e985 Move Approx's validity checks out of line into cpp file
This avoids having to include <stdexcept> in the main include path
and speeds up the compilation if Approx is used with multiple
different types.
2018-09-03 10:15:51 +02:00

95 lines
2.6 KiB
C++

/*
* Created by Martin on 19/07/2017.
* Copyright 2017 Two Blue Cubes Ltd. All rights reserved.
*
* Distributed under the Boost Software License, Version 1.0. (See accompanying
* file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
*/
#include "catch_approx.h"
#include <cmath>
#include <limits>
#include <stdexcept>
namespace {
// Performs equivalent check of std::fabs(lhs - rhs) <= margin
// But without the subtraction to allow for INFINITY in comparison
bool marginComparison(double lhs, double rhs, double margin) {
return (lhs + margin >= rhs) && (rhs + margin >= lhs);
}
}
namespace Catch {
namespace Detail {
Approx::Approx ( double value )
: m_epsilon( std::numeric_limits<float>::epsilon()*100 ),
m_margin( 0.0 ),
m_scale( 0.0 ),
m_value( value )
{}
Approx Approx::custom() {
return Approx( 0 );
}
Approx Approx::operator-() const {
auto temp(*this);
temp.m_value = -temp.m_value;
return temp;
}
std::string Approx::toString() const {
ReusableStringStream rss;
rss << "Approx( " << ::Catch::Detail::stringify( m_value ) << " )";
return rss.str();
}
bool Approx::equalityComparisonImpl(const double other) const {
// First try with fixed margin, then compute margin based on epsilon, scale and Approx's value
// Thanks to Richard Harris for his help refining the scaled margin value
return marginComparison(m_value, other, m_margin) || marginComparison(m_value, other, m_epsilon * (m_scale + std::fabs(m_value)));
}
void Approx::setMargin(double margin) {
if (margin < 0) {
throw std::domain_error
("Invalid Approx::margin: " +
Catch::Detail::stringify(margin) +
", Approx::Margin has to be non-negative.");
}
m_margin = margin;
}
void Approx::setEpsilon(double epsilon) {
if (epsilon < 0 || epsilon > 1.0) {
throw std::domain_error
("Invalid Approx::epsilon: " +
Catch::Detail::stringify(epsilon) +
", Approx::epsilon has to be between 0 and 1");
}
m_epsilon = epsilon;
}
} // end namespace Detail
namespace literals {
Detail::Approx operator "" _a(long double val) {
return Detail::Approx(val);
}
Detail::Approx operator "" _a(unsigned long long val) {
return Detail::Approx(val);
}
} // end namespace literals
std::string StringMaker<Catch::Detail::Approx>::convert(Catch::Detail::Approx const& value) {
return value.toString();
}
} // end namespace Catch