Further refactoring

defaultrule/no-else-return-rule.go

@@ -14,15 +14,15 @@ const (
 )
 
 // LintElseRule lints given else constructs.
-type LintElseRule struct {
-	rule.AbstractRule
-}
+type LintElseRule struct{}
 
 // Apply applies the rule to given file.
 func (r *LintElseRule) Apply(file *file.File, arguments rule.Arguments) []rule.Failure {
-	r.File = file
-	ast.Walk(lintElse{r}, file.GetAST())
-	return r.Failures()
+	var failures []rule.Failure
+	ast.Walk(lintElse(func(failure rule.Failure) {
+		failures = append(failures, failure)
+	}), file.GetAST())
+	return failures
 }
 
 // Name returns the rule name.
@@ -30,9 +30,7 @@ func (r *LintElseRule) Name() string {
 	return ruleName
 }
 
-type lintElse struct {
-	r *LintElseRule
-}
+type lintElse func(rule.Failure)
 
 func (f lintElse) Visit(n ast.Node) ast.Visitor {
 	node, ok := n.(*ast.IfStmt)
@@ -55,10 +53,11 @@ func (f lintElse) Visit(n ast.Node) ast.Visitor {
 		}
 		lastStmt := node.Body.List[len(node.Body.List)-1]
 		if _, ok := lastStmt.(*ast.ReturnStmt); ok {
-			f.r.AddFailureAtNode(rule.Failure{
+			f(rule.Failure{
 				Failure: failure,
 				Type:    rule.FailureTypeWarning,
-			}, node.Else, f.r.File)
+				Node:    node.Else,
+			})
 			return f
 		}
 	}

linter/linter.go

@@ -46,13 +46,16 @@ func (l *Linter) Lint(filenames []string, ruleSet []rule.Rule) ([]rule.Failure,
 			return nil, err
 		}
 
-		for _, rule := range ruleSet {
-			currentFailures := rule.Apply(file, []string{})
+		for _, currentRule := range ruleSet {
+			currentFailures := currentRule.Apply(file, []string{})
 			for idx, failure := range currentFailures {
 				if failure.RuleName == "" {
-					failure.RuleName = rule.Name()
-					currentFailures[idx] = failure
+					failure.RuleName = currentRule.Name()
 				}
+				if failure.Node != nil {
+					failure.Position = rule.ToFailurePosition(failure.Node.Pos(), failure.Node.End(), file)
+				}
+				currentFailures[idx] = failure
 			}
 			currentFailures = l.filterFailures(currentFailures, disabledIntervals)
 			failures = append(failures, currentFailures...)

rule/rule.go

@@ -29,7 +29,7 @@ type Failure struct {
 	RuleName string
 	Type     FailureType
 	Position FailurePosition
-	file     *file.File
+	Node     ast.Node
 }
 
 // GetFilename returns the filename.
@@ -57,33 +57,15 @@ type Config struct {
 type Rule interface {
 	Name() string
 	Apply(*file.File, Arguments) []Failure
-	AddFailures(...Failure)
-	Failures() []Failure
 }
 
 // AbstractRule defines an abstract rule.
 type AbstractRule struct {
-	failures []Failure
-	File     *file.File
+	Failures []Failure
 }
 
-// AddFailures adds rule failures.
-func (r *AbstractRule) AddFailures(failures ...Failure) {
-	r.failures = append(r.failures, failures...)
-}
-
-// AddFailureAtNode adds rule failure at specific node.
-func (r *AbstractRule) AddFailureAtNode(failure Failure, t ast.Node, file *file.File) {
-	failure.Position = toFailurePosition(t.Pos(), t.End(), file)
-	r.AddFailures(failure)
-}
-
-// Failures returns the rule failures.
-func (r *AbstractRule) Failures() []Failure {
-	return r.failures
-}
-
-func toFailurePosition(start token.Pos, end token.Pos, file *file.File) FailurePosition {
+// ToFailurePosition returns the failure position.
+func ToFailurePosition(start token.Pos, end token.Pos, file *file.File) FailurePosition {
 	return FailurePosition{
 		Start: file.ToPosition(start),
 		End:   file.ToPosition(end),