1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
|
// Copyright Catch2 Authors
// Distributed under the Boost Software License, Version 1.0.
// (See accompanying file LICENSE.txt or copy at
// https://www.boost.org/LICENSE_1_0.txt)
// SPDX-License-Identifier: BSL-1.0
#include <catch2/matchers/catch_matchers_floating_point.hpp>
#include <catch2/internal/catch_enforce.hpp>
#include <catch2/internal/catch_polyfills.hpp>
#include <catch2/internal/catch_to_string.hpp>
#include <catch2/catch_tostring.hpp>
#include <catch2/internal/catch_floating_point_helpers.hpp>
#include <algorithm>
#include <cmath>
#include <cstdlib>
#include <cstdint>
#include <sstream>
#include <iomanip>
#include <limits>
namespace Catch {
namespace {
template <typename FP>
bool almostEqualUlps(FP lhs, FP rhs, uint64_t maxUlpDiff) {
// Comparison with NaN should always be false.
// This way we can rule it out before getting into the ugly details
if (Catch::isnan(lhs) || Catch::isnan(rhs)) {
return false;
}
// This should also handle positive and negative zeros, infinities
const auto ulpDist = ulpDistance(lhs, rhs);
return ulpDist <= maxUlpDiff;
}
template <typename FP>
FP step(FP start, FP direction, uint64_t steps) {
for (uint64_t i = 0; i < steps; ++i) {
start = Catch::nextafter(start, direction);
}
return start;
}
// 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);
}
template <typename FloatingPoint>
void write(std::ostream& out, FloatingPoint num) {
out << std::scientific
<< std::setprecision(std::numeric_limits<FloatingPoint>::max_digits10 - 1)
<< num;
}
} // end anonymous namespace
namespace Matchers {
namespace Detail {
enum class FloatingPointKind : uint8_t {
Float,
Double
};
} // end namespace Detail
WithinAbsMatcher::WithinAbsMatcher(double target, double margin)
:m_target{ target }, m_margin{ margin } {
CATCH_ENFORCE(margin >= 0, "Invalid margin: " << margin << '.'
<< " Margin has to be non-negative.");
}
// Performs equivalent check of std::fabs(lhs - rhs) <= margin
// But without the subtraction to allow for INFINITY in comparison
bool WithinAbsMatcher::match(double const& matchee) const {
return (matchee + m_margin >= m_target) && (m_target + m_margin >= matchee);
}
std::string WithinAbsMatcher::describe() const {
return "is within " + ::Catch::Detail::stringify(m_margin) + " of " + ::Catch::Detail::stringify(m_target);
}
WithinUlpsMatcher::WithinUlpsMatcher(double target, uint64_t ulps, Detail::FloatingPointKind baseType)
:m_target{ target }, m_ulps{ ulps }, m_type{ baseType } {
CATCH_ENFORCE(m_type == Detail::FloatingPointKind::Double
|| m_ulps < (std::numeric_limits<uint32_t>::max)(),
"Provided ULP is impossibly large for a float comparison.");
CATCH_ENFORCE( std::numeric_limits<double>::is_iec559,
"WithinUlp matcher only supports platforms with "
"IEEE-754 compatible floating point representation" );
}
#if defined(__clang__)
#pragma clang diagnostic push
// Clang <3.5 reports on the default branch in the switch below
#pragma clang diagnostic ignored "-Wunreachable-code"
#endif
bool WithinUlpsMatcher::match(double const& matchee) const {
switch (m_type) {
case Detail::FloatingPointKind::Float:
return almostEqualUlps<float>(static_cast<float>(matchee), static_cast<float>(m_target), m_ulps);
case Detail::FloatingPointKind::Double:
return almostEqualUlps<double>(matchee, m_target, m_ulps);
default:
CATCH_INTERNAL_ERROR( "Unknown Detail::FloatingPointKind value" );
}
}
#if defined(__clang__)
#pragma clang diagnostic pop
#endif
std::string WithinUlpsMatcher::describe() const {
std::stringstream ret;
ret << "is within " << m_ulps << " ULPs of ";
if (m_type == Detail::FloatingPointKind::Float) {
write(ret, static_cast<float>(m_target));
ret << 'f';
} else {
write(ret, m_target);
}
ret << " ([";
if (m_type == Detail::FloatingPointKind::Double) {
write( ret,
step( m_target,
-std::numeric_limits<double>::infinity(),
m_ulps ) );
ret << ", ";
write( ret,
step( m_target,
std::numeric_limits<double>::infinity(),
m_ulps ) );
} else {
// We have to cast INFINITY to float because of MinGW, see #1782
write( ret,
step( static_cast<float>( m_target ),
-std::numeric_limits<float>::infinity(),
m_ulps ) );
ret << ", ";
write( ret,
step( static_cast<float>( m_target ),
std::numeric_limits<float>::infinity(),
m_ulps ) );
}
ret << "])";
return ret.str();
}
WithinRelMatcher::WithinRelMatcher(double target, double epsilon):
m_target(target),
m_epsilon(epsilon){
CATCH_ENFORCE(m_epsilon >= 0., "Relative comparison with epsilon < 0 does not make sense.");
CATCH_ENFORCE(m_epsilon < 1., "Relative comparison with epsilon >= 1 does not make sense.");
}
bool WithinRelMatcher::match(double const& matchee) const {
const auto relMargin = m_epsilon * (std::max)(std::fabs(matchee), std::fabs(m_target));
return marginComparison(matchee, m_target,
std::isinf(relMargin)? 0 : relMargin);
}
std::string WithinRelMatcher::describe() const {
Catch::ReusableStringStream sstr;
sstr << "and " << ::Catch::Detail::stringify(m_target) << " are within " << m_epsilon * 100. << "% of each other";
return sstr.str();
}
WithinUlpsMatcher WithinULP(double target, uint64_t maxUlpDiff) {
return WithinUlpsMatcher(target, maxUlpDiff, Detail::FloatingPointKind::Double);
}
WithinUlpsMatcher WithinULP(float target, uint64_t maxUlpDiff) {
return WithinUlpsMatcher(target, maxUlpDiff, Detail::FloatingPointKind::Float);
}
WithinAbsMatcher WithinAbs(double target, double margin) {
return WithinAbsMatcher(target, margin);
}
WithinRelMatcher WithinRel(double target, double eps) {
return WithinRelMatcher(target, eps);
}
WithinRelMatcher WithinRel(double target) {
return WithinRelMatcher(target, std::numeric_limits<double>::epsilon() * 100);
}
WithinRelMatcher WithinRel(float target, float eps) {
return WithinRelMatcher(target, eps);
}
WithinRelMatcher WithinRel(float target) {
return WithinRelMatcher(target, std::numeric_limits<float>::epsilon() * 100);
}
bool IsNaNMatcher::match( double const& matchee ) const {
return std::isnan( matchee );
}
std::string IsNaNMatcher::describe() const {
using namespace std::string_literals;
return "is NaN"s;
}
IsNaNMatcher IsNaN() { return IsNaNMatcher(); }
} // namespace Matchers
} // namespace Catch
|
