feat: use inspect.Analyzer for optimized traversal

Author: tdakkota

asciicheck.go

@@ -6,63 +6,72 @@ import (
 	"go/token"
 
 	"golang.org/x/tools/go/analysis"
+	"golang.org/x/tools/go/analysis/passes/inspect"
+	"golang.org/x/tools/go/ast/inspector"
 )
 
 func NewAnalyzer() *analysis.Analyzer {
 	return &analysis.Analyzer{
-		Name: "asciicheck",
-		Doc:  "checks that all code identifiers does not have non-ASCII symbols in the name",
-		Run:  run,
+		Name:     "asciicheck",
+		Doc:      "checks that all code identifiers does not have non-ASCII symbols in the name",
+		Requires: []*analysis.Analyzer{inspect.Analyzer},
+		Run:      run,
 	}
 }
 
 func run(pass *analysis.Pass) (any, error) {
-	for _, file := range pass.Files {
-		ast.Inspect(
-			file, func(node ast.Node) bool {
-				cb(pass, node)
-				return true
-			},
-		)
+	inspect := pass.ResultOf[inspect.Analyzer].(*inspector.Inspector)
+
+	nodeFilter := []ast.Node{
+		(*ast.File)(nil),
+		(*ast.ImportSpec)(nil),
+		(*ast.TypeSpec)(nil),
+		(*ast.ValueSpec)(nil),
+		(*ast.FuncDecl)(nil),
+		(*ast.StructType)(nil),
+		(*ast.FuncType)(nil),
+		(*ast.InterfaceType)(nil),
+		(*ast.LabeledStmt)(nil),
+		(*ast.AssignStmt)(nil),
 	}
-	return nil, nil
-}
 
-func cb(pass *analysis.Pass, n ast.Node) {
-	switch n := n.(type) {
-	case *ast.File:
-		checkIdent(pass, n.Name)
-	case *ast.ImportSpec:
-		checkIdent(pass, n.Name)
-	case *ast.TypeSpec:
-		checkIdent(pass, n.Name)
-		checkFieldList(pass, n.TypeParams)
-	case *ast.ValueSpec:
-		for _, name := range n.Names {
-			checkIdent(pass, name)
-		}
-	case *ast.FuncDecl:
-		checkIdent(pass, n.Name)
-		checkFieldList(pass, n.Recv)
-	case *ast.StructType:
-		checkFieldList(pass, n.Fields)
-	case *ast.FuncType:
-		checkFieldList(pass, n.TypeParams)
-		checkFieldList(pass, n.Params)
-		checkFieldList(pass, n.Results)
-	case *ast.InterfaceType:
-		checkFieldList(pass, n.Methods)
-	case *ast.LabeledStmt:
-		checkIdent(pass, n.Label)
-	case *ast.AssignStmt:
-		if n.Tok == token.DEFINE {
-			for _, expr := range n.Lhs {
-				if ident, ok := expr.(*ast.Ident); ok {
-					checkIdent(pass, ident)
+	inspect.Preorder(nodeFilter, func(n ast.Node) {
+		switch n := n.(type) {
+		case *ast.File:
+			checkIdent(pass, n.Name)
+		case *ast.ImportSpec:
+			checkIdent(pass, n.Name)
+		case *ast.TypeSpec:
+			checkIdent(pass, n.Name)
+			checkFieldList(pass, n.TypeParams)
+		case *ast.ValueSpec:
+			for _, name := range n.Names {
+				checkIdent(pass, name)
+			}
+		case *ast.FuncDecl:
+			checkIdent(pass, n.Name)
+			checkFieldList(pass, n.Recv)
+		case *ast.StructType:
+			checkFieldList(pass, n.Fields)
+		case *ast.FuncType:
+			checkFieldList(pass, n.TypeParams)
+			checkFieldList(pass, n.Params)
+			checkFieldList(pass, n.Results)
+		case *ast.InterfaceType:
+			checkFieldList(pass, n.Methods)
+		case *ast.LabeledStmt:
+			checkIdent(pass, n.Label)
+		case *ast.AssignStmt:
+			if n.Tok == token.DEFINE {
+				for _, expr := range n.Lhs {
+					if ident, ok := expr.(*ast.Ident); ok {
+						checkIdent(pass, ident)
+					}
 				}
 			}
 		}
-	}
+	})
+	return nil, nil
 }
 
 func checkIdent(pass *analysis.Pass, v *ast.Ident) {