英文:
How to compare Go slices with NaN elements in unit tests?
问题
我需要在单元测试中比较两个切片，我认为assert包应该可以解决这个问题，但它不能处理NaN值：
import (
"github.com/stretchr/testify/assert"
)
func CallMe() []float64 {
return []float64{math.NaN()}
}
func TestCallMe(t *testing.T) {
assert.Equal(t, []float64{math.NaN()}, CallMe())
}
输出结果为：
Error: Not equal:
expected: []float64{NaN}
actual : []float64{NaN}
Diff:
Test: TestCallMe
我理解NaN的特性是它不等于自身，但另一方面，我从函数中得到了预期的结果。
我想知道如何解决这个问题-如何拥有简洁的单元测试断言和清晰的输出？
作为一种替代方案，我可以避免使用assert，并在两个切片的每个元素上调用math.IsNaN，但这在单元测试中看起来会显得冗长。
英文:
I need to compare 2 slices in unit tests and I thought assert package should solve this but it doesn't work with NaNs:
import (
"github.com/stretchr/testify/assert"
)
func CallMe() []float64 {
return []float64{math.NaN()}
}
func TestCallMe(t *testing.T) {
assert.Equal(t, []float64{math.NaN()}, CallMe())
}
The output is:
Error: Not equal:
expected: []float64{NaN}
actual : []float64{NaN}
Diff:
Test: TestCallMe
I understand that it's a property of NaN to be not equal to itself but on the other hand I receive the expected result from the function.
I wonder how to solve that - to have a concise unit test assertion and a clear output?
As an alternative I can avoid using assert and call math.IsNaN on every element of both slices but that will look extra verbose in unit tests.
答案1
得分: 1
github.com/google/go-cmp/cmp 包通常推荐用于更复杂的比较。cmpopts.EquateNaNs 可以用于轻松比较可能包含 NaN 的数据结构。
package calc_test
import (
"math"
"testing"
"github.com/google/go-cmp/cmp"
"github.com/google/go-cmp/cmp/cmpopts"
)
func calc(n float64) []float64 {
return []float64{n, math.NaN()}
}
func TestCalc(t *testing.T) {
want := []float64{1, math.NaN()}
got := calc(1) // 通过。
if !cmp.Equal(got, want, cmpopts.EquateNaNs()) {
t.Errorf("calc: got = %v; want = %v", got, want)
}
got = calc(2) // 失败，有差异。
if diff := cmp.Diff(want, got, cmpopts.EquateNaNs()); diff != "" {
t.Errorf("calc: diff (-want +got) = \n%s", diff)
}
}
英文:
The github.com/google/go-cmp/cmp package is typically recommended for more complex comparisons. cmpopts.EquateNaNs can be used to easily compare data structures which may contain NaNs.
package calc_test
import (
"math"
"testing"
"github.com/google/go-cmp/cmp"
"github.com/google/go-cmp/cmp/cmpopts"
)
func calc(n float64) []float64 {
return []float64{n, math.NaN()}
}
func TestCalc(t *testing.T) {
want := []float64{1, math.NaN()}
got := calc(1) // PASS.
if !cmp.Equal(got, want, cmpopts.EquateNaNs()) {
t.Errorf("calc: got = %v; want = %v", got, want)
}
got = calc(2) // FAIL with differences.
if diff := cmp.Diff(want, got, cmpopts.EquateNaNs()); diff != "" {
t.Errorf("calc: diff (-want +got) = \n%s", diff)
}
}
通过集体智慧和协作来改善编程学习和解决问题的方式。致力于成为全球开发者共同参与的知识库，让每个人都能够通过互相帮助和分享经验来进步。
评论