断言： mock：我不知道要返回什么(即使我已经声明了模拟函数和返回)

Question

我使用Testify为我的golang应用程序创建一个单元测试。我需要为这个函数创建一个单元测试，它调用一个可变函数(带有尾随参数的函数(。我在测试它时遇到了一个错误。实际上，我不确定这个错误是否是因为后面的参数本身，但我觉得mock有问题。

// svc/callThisFunction.go
// data type of args is []sqkit.SelectOption
func CallThisFunction(ctx context.Context, args ...sqkit.SelectFunctiom) (result string, err error) {
return result, nil
}
// svc/functionToTest.go
// This is the function that I wanna test
func FunctionToTest(ctx context.Context, id int64) (result string, err error) {
args := []sqkit.SelectOption{
sqkit.Where{
fmt.Sprintf("id = %d", id),
},
}
newResult, err := callThisFunctionService.CallThisFunction(ctx, args)
if err != nil {
return newResult, err
}
return newResult, nil
}

// svc/functionToTest_test.go
func Test_FunctionToTest(t *testing.T) {
testCase := []struct {
name string
id int64
onCallThisFunctionMock func(callThisFunctionSvc *mocks.CallThisFunctionSvc)
expectedResult string
wantError bool
expectedError error  
}{
{
name: "Success",
id: 1,
onCallThisFunctionMock: func(callThisFunctionSvc *mocks.CallThisFunctionSvc) {
// NOTE: I've created 2 different versions (used separately, not at the same), using mock.Anything() and using actual arguments
// Both of these give the same errors
// Using actual arguments          
args := []sqkit.SelectOption{
sqkit.Where{
fmt.Sprintf("id = %d", 1},
},
}
callThisFunctionSvc.On("CallThisFunction", context.Background(), args).Return("Success", nil)
// Using mock.Anything
callThisFunctionSvc.On("CallThisFunction", context.Background(), mock.Anything).Return("Success", nil)
}
}
}
for _, tc := range testCases {
var callThisFunctionSvc = new(mocks.CallThisFunctionSvc)
tc.onCallThisFunctionMock(callThisFunctionSvc)
svc := &svc.FunctionToTest{
CallThisFunction: callThisFunctionSvc,
}
actualResult, actualError := svc.FunctionToTest(context.Background(), tc.id)
if tc.wantEror {
require.Error(t, actualError, tc.expectedError)
} else {
require.NoError(t, actualError)
}
require.Equal(t, tc.expectedResult, actualResult)
}
}

这是它给的错误

=== RUN   Test_GenerateDocument
--- FAIL: Test_GenerateDocument (0.00s)
panic: 
assert: mock: I don't know what to return because the method call was unexpected.
Either do Mock.On("CallThisFunction").Return(...) first, or remove the GetTemplates() call.
This method was unexpected:
CallThisFunction(*context.emptyCtx,sqkit.Where)
0: (*context.emptyCtx)(0xc0000a4010)
1: sqkit.Where{"id = 1"}

通常，当我遇到这样的错误时，是因为我没有在我想要测试的函数中定义函数调用的返回值。但这一次我创建了它，但不知何故它无法读取返回。知道为什么吗？

Answer 1

错误表明您使用参数(context.Context, sqkit.Where)调用了CallThisFuncion，但您的示例使用并设置了对(context.Context, []sqkit.Option)的期望值。mock.Anything的示例应该有效，但我认为由于上下文的原因，它失败了。你需要用你传递的相同上下文来设定期望值。如果FunctionToTest要更改上下文，我认为您需要使用mock.Anything。

func Test_FunctionToTest(t *testing.T) {
testCase := []struct {
name string
id int64
onCallThisFunctionMock func(context.Context, *mocks.CallThisFunctionSvc)
expectedResult string
wantError bool
expectedError error  
}{
{
name: "Success",
id: 1,
onCallThisFunctionMock: func(ctx context.Context, callThisFunctionSvc *mocks.CallThisFunctionSvc) {
args := []sqkit.SelectOption{
sqkit.Where{
fmt.Sprintf("id = %d", 1},
},
}
callThisFunctionSvc.On("CallThisFunction", ctx, args).Return("Success", nil)
}
}
}
for _, tc := range testCases {
var callThisFunctionSvc = new(mocks.CallThisFunctionSvc)
var ctx = context.Background()
tc.onCallThisFunctionMock(ctx, callThisFunctionSvc)
svc := &svc.FunctionToTest{
CallThisFunction: callThisFunctionSvc,
}
actualResult, actualError := svc.FunctionToTest(ctx, tc.id)
if tc.wantEror {
require.Error(t, actualError, tc.expectedError)
} else {
require.NoError(t, actualError)
}
require.Equal(t, tc.expectedResult, actualResult)
}
}

如果您希望确保context.Context作为第一个参数传递，但不关心什么上下文，则可以使用AnythingOfType。

callThisFunctionSvc.On("CallThisFunction", mock.AnythingOfType("context.Context"), args).Return("Success", nil)