README
¶
interfacer
A linter that suggests interface types. In other words, it warns about the usage of types that are more specific than necessary.
go get -u github.com/mvdan/interfacer/cmd/interfacer
Usage
func ProcessInput(f *os.File) error {
b, err := ioutil.ReadAll(f)
if err != nil {
return err
}
return processBytes(b)
}
$ interfacer $(go list ./... | grep -v /vendor/)
foo.go:10:19: f can be io.Reader
Basic idea
This tool inspects the parameters of your functions to see if they fit an interface type that is less specific than the current type.
The example above illustrates this point. Overly specific interfaces
also trigger a warning - if f were an io.ReadCloser, the same
message would appear.
It suggests interface types defined both in the func's package and the package's imports (two levels; direct imports and their direct imports).
False positives
To avoid false positives, it never does any suggestions on functions that may be implementing an interface method or a named function type.
It also skips parameters passed by value (excluding pointers and interfaces) on unexported functions, since that would introduce extra allocations where they are usually not worth the tradeoff.
Suppressing warnings
If a suggestion is technically correct but doesn't make sense, you can still suppress the warning by mentioning the type in the function name:
func ProcessInputFile(f *os.File) error {
// use as an io.Reader
}
Documentation
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Index ¶
Constants ¶
This section is empty.
Variables ¶
This section is empty.
Functions ¶
func Interfacer ¶
Types ¶
type Checker ¶
type Checker struct {
*loader.PackageInfo
// contains filtered or unexported fields
}
Source Files