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37 * Tests \Gromacs-specific test assertions.
39 * \author Teemu Murtola <teemu.murtola@gmail.com>
40 * \ingroup module_testutils
44 #include "testutils/testasserts.h"
46 #include <gtest/gtest.h>
51 using ::testing::internal::FloatingPoint;
54 * Helper to produce floating-point numbers with specified ULP difference.
56 * This doesn't work if the value would change sign.
58 * \ingroup module_testutils
60 template <typename FloatType>
61 FloatType addUlps(FloatType value, int ulps)
63 return FloatingPoint<FloatType>::ReinterpretBits(
64 FloatingPoint<FloatType>(value).bits() + ulps);
67 using ::gmx::test::FloatingPointDifference;
69 TEST(FloatingPointDifferenceTest, HandlesEqualValues)
71 FloatingPointDifference diff(1.2, 1.2);
72 EXPECT_FALSE(diff.isNaN());
73 EXPECT_EQ(0.0, diff.asAbsolute());
74 EXPECT_EQ(0U, diff.asUlps());
75 EXPECT_FALSE(diff.signsDiffer());
78 TEST(FloatingPointDifferenceTest, HandlesZerosOfDifferentSign)
80 FloatingPointDifference diff(0.0, GMX_DOUBLE_NEGZERO);
81 EXPECT_FALSE(diff.isNaN());
82 EXPECT_EQ(0.0, diff.asAbsolute());
83 EXPECT_EQ(0U, diff.asUlps());
84 EXPECT_TRUE(diff.signsDiffer());
87 TEST(FloatingPointDifferenceTest, HandlesSignComparisonWithZero)
90 FloatingPointDifference diff(0.0, -1.2);
91 EXPECT_FALSE(diff.isNaN());
92 EXPECT_DOUBLE_EQ(1.2, diff.asAbsolute());
93 EXPECT_TRUE(diff.signsDiffer());
96 FloatingPointDifference diff(GMX_DOUBLE_NEGZERO, -1.2);
97 EXPECT_FALSE(diff.isNaN());
98 EXPECT_DOUBLE_EQ(1.2, diff.asAbsolute());
99 EXPECT_FALSE(diff.signsDiffer());
103 TEST(FloatingPointDifferenceTest, HandlesUlpDifferences)
105 const double first = 1.0;
106 const double second = addUlps(first, 2);
108 FloatingPointDifference diff(first, second);
109 EXPECT_FALSE(diff.isNaN());
110 EXPECT_DOUBLE_EQ(second - first, diff.asAbsolute());
111 EXPECT_EQ(2U, diff.asUlps());
112 EXPECT_FALSE(diff.signsDiffer());
115 FloatingPointDifference diff(second, first);
116 EXPECT_FALSE(diff.isNaN());
117 EXPECT_DOUBLE_EQ(second - first, diff.asAbsolute());
118 EXPECT_EQ(2U, diff.asUlps());
119 EXPECT_FALSE(diff.signsDiffer());
123 TEST(FloatingPointDifferenceTest, HandlesUlpDifferenceAcrossZero)
125 const double first = addUlps(GMX_DOUBLE_NEGZERO, 2);
126 const double second = addUlps( 0.0, 2);
127 FloatingPointDifference diff(first, second);
128 EXPECT_FALSE(diff.isNaN());
129 EXPECT_DOUBLE_EQ(second - first, diff.asAbsolute());
130 EXPECT_EQ(4U, diff.asUlps());
131 EXPECT_TRUE(diff.signsDiffer());
134 TEST(FloatingPointDifferenceTest, HandlesNaN)
136 const double first = std::numeric_limits<double>::quiet_NaN();
137 const double second = 2.0;
138 FloatingPointDifference diff(first, second);
139 EXPECT_TRUE(diff.isNaN());