refactor: replace failure Category raw string with constant (#1196)

* refactor: replace Category raw strings with constants

* Add type FailureCategory; add comments for constants

Author: alexandear

lint/failure.go

@@ -5,6 +5,53 @@ import (
 	"go/token"
 )
 
+const (
+	// FailureCategoryArgOrder indicates argument order issues.
+	FailureCategoryArgOrder FailureCategory = "arg-order"
+	// FailureCategoryBadPractice indicates bad practice issues.
+	FailureCategoryBadPractice FailureCategory = "bad practice"
+	// FailureCategoryCodeStyle indicates code style issues.
+	FailureCategoryCodeStyle FailureCategory = "code-style"
+	// FailureCategoryComments indicates comment issues.
+	FailureCategoryComments FailureCategory = "comments"
+	// FailureCategoryComplexity indicates complexity issues.
+	FailureCategoryComplexity FailureCategory = "complexity"
+	// FailureCategoryContent indicates content issues.
+	FailureCategoryContent FailureCategory = "content"
+	// FailureCategoryErrors indicates error handling issues.
+	FailureCategoryErrors FailureCategory = "errors"
+	// FailureCategoryImports indicates import issues.
+	FailureCategoryImports FailureCategory = "imports"
+	// FailureCategoryLogic indicates logic issues.
+	FailureCategoryLogic FailureCategory = "logic"
+	// FailureCategoryMaintenance indicates maintenance issues.
+	FailureCategoryMaintenance FailureCategory = "maintenance"
+	// FailureCategoryNaming indicates naming issues.
+	FailureCategoryNaming FailureCategory = "naming"
+	// FailureCategoryOptimization indicates optimization issues.
+	FailureCategoryOptimization FailureCategory = "optimization"
+	// FailureCategoryStyle indicates style issues.
+	FailureCategoryStyle FailureCategory = "style"
+	// FailureCategoryTime indicates time-related issues.
+	FailureCategoryTime FailureCategory = "time"
+	// FailureCategoryTypeInference indicates type inference issues.
+	FailureCategoryTypeInference FailureCategory = "type-inference"
+	// FailureCategoryUnaryOp indicates unary operation issues.
+	FailureCategoryUnaryOp FailureCategory = "unary-op"
+	// FailureCategoryUnexportedTypeInAPI indicates unexported type in API issues.
+	FailureCategoryUnexportedTypeInAPI FailureCategory = "unexported-type-in-api"
+	// FailureCategoryZeroValue indicates zero value issues.
+	FailureCategoryZeroValue FailureCategory = "zero-value"
+
+	// failureCategoryInternal indicates internal failures.
+	failureCategoryInternal FailureCategory = "REVIVE_INTERNAL"
+	// failureCategoryValidity indicates validity issues.
+	failureCategoryValidity FailureCategory = "validity"
+)
+
+// FailureCategory is the type for the failure categories.
+type FailureCategory string
+
 const (
 	// SeverityWarning declares failures of type warning
 	SeverityWarning = "warning"
@@ -25,7 +72,7 @@ type FailurePosition struct {
 type Failure struct {
 	Failure    string
 	RuleName   string
-	Category   string
+	Category   FailureCategory
 	Position   FailurePosition
 	Node       ast.Node `json:"-"`
 	Confidence float64
@@ -38,17 +85,15 @@ func (f *Failure) GetFilename() string {
 	return f.Position.Start.Filename
 }
 
-const internalFailure = "REVIVE_INTERNAL"
-
 // IsInternal returns true if this failure is internal, false otherwise.
 func (f *Failure) IsInternal() bool {
-	return f.Category == internalFailure
+	return f.Category == failureCategoryInternal
 }
 
 // NewInternalFailure yields an internal failure with the given message as failure message.
 func NewInternalFailure(message string) Failure {
 	return Failure{
-		Category: internalFailure,
+		Category: failureCategoryInternal,
 		Failure:  message,
 	}
 }

lint/linter.go

@@ -223,7 +223,7 @@ func addInvalidFileFailure(filename, errStr string, failures chan Failure) {
 	failures <- Failure{
 		Confidence: 1,
 		Failure:    fmt.Sprintf("invalid file %s: %v", filename, errStr),
-		Category:   "validity",
+		Category:   failureCategoryValidity,
 		Position:   position,
 	}
 }