I am using err113
as part of golangci-lint
.
It is complaining about ...
foo_test.go:55:61: err113: do not define dynamic errors, use wrapped static errors instead: "errors.New(\"repo gave err\")" (goerr113)
repoMock.EXPECT().Save(gomock.Eq(&foooBarBar)).Return(nil, errors.New("repo gave err")),
^
foo_test.go:22:42: err113: do not define dynamic errors, use wrapped static errors instead: "errors.New(\"oops\")" (goerr113)
repoMock.EXPECT().FindAll().Return(nil, errors.New("oops"))
^
What is best way to fix this ?
Quoting https://github.com/Djarvur/go-err113
Also, any call of errors.New() and fmt.Errorf() methods are reported except the calls used to initialise package-level variables and the fmt.Errorf() calls wrapping the other errors.
I am trying to get a idiomatic example for this.
Declare a package-level variables as suggested:
var repoGaveErr = errors.New("repo gave err")
func someFunc() {
repoMock.EXPECT().Save(gomock.Eq(&foooBarBar)).Return(nil, repoGaveErr)
}
Every call to errors.New allocates a new unique error value. The application creates a single value representing the error by declaring the package-level variable.
There are two motivations for the single value:
The application can compare values for equality to check for a specific error condition.
Reduce memory allocations (although probably not a big deal in practice)
The value io.EOF is a canonical example.