/
error-return.go
67 lines (57 loc) 路 1.37 KB
/
error-return.go
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package rule
import (
"go/ast"
"github.com/mgechev/revive/lint"
)
// ErrorReturnRule lints given else constructs.
type ErrorReturnRule struct{}
// Apply applies the rule to given file.
func (*ErrorReturnRule) Apply(file *lint.File, _ lint.Arguments) []lint.Failure {
var failures []lint.Failure
fileAst := file.AST
walker := lintErrorReturn{
file: file,
fileAst: fileAst,
onFailure: func(failure lint.Failure) {
failures = append(failures, failure)
},
}
ast.Walk(walker, fileAst)
return failures
}
// Name returns the rule name.
func (*ErrorReturnRule) Name() string {
return "error-return"
}
type lintErrorReturn struct {
file *lint.File
fileAst *ast.File
onFailure func(lint.Failure)
}
func (w lintErrorReturn) Visit(n ast.Node) ast.Visitor {
fn, ok := n.(*ast.FuncDecl)
if !ok || fn.Type.Results == nil {
return w
}
ret := fn.Type.Results.List
if len(ret) <= 1 {
return w
}
if isIdent(ret[len(ret)-1].Type, "error") {
return nil
}
// An error return parameter should be the last parameter.
// Flag any error parameters found before the last.
for _, r := range ret[:len(ret)-1] {
if isIdent(r.Type, "error") {
w.onFailure(lint.Failure{
Category: "arg-order",
Confidence: 0.9,
Node: fn,
Failure: "error should be the last type when returning multiple items",
})
break // only flag one
}
}
return w
}