fix: generateFuncTypeName ignores field names for stable WithArgType/WithResultType matching

Author: dingsongjie

plugins/core/instrument/enhance.go

@@ -94,41 +94,55 @@ func generateTypeNameByExp(exp dst.Expr) string {
 func generateFuncTypeName(n *dst.FuncType) string {
 	result := "func("
 	if n.Params != nil {
-		for i, field := range n.Params.List {
-			if i > 0 {
-				result += ", "
+		first := true
+		for _, field := range n.Params.List {
+			count := len(field.Names)
+			if count == 0 {
+				count = 1
 			}
-			if len(field.Names) > 0 {
-				for j, name := range field.Names {
-					if j > 0 {
-						result += ", "
-					}
-					result += name.Name + " " + generateTypeNameByExp(field.Type)
+			for k := 0; k < count; k++ {
+				if !first {
+					result += ", "
 				}
-			} else {
 				result += generateTypeNameByExp(field.Type)
+				first = false
 			}
 		}
 	}
 	result += ")"
 	if n.Results != nil && len(n.Results.List) > 0 {
-		if len(n.Results.List) == 1 && len(n.Results.List[0].Names) == 0 {
-			result += " " + generateTypeNameByExp(n.Results.List[0].Type)
+		totalResults := 0
+		for _, field := range n.Results.List {
+			if len(field.Names) == 0 {
+				totalResults++
+			} else {
+				totalResults += len(field.Names)
+			}
+		}
+		if totalResults == 1 {
+			for _, field := range n.Results.List {
+				count := len(field.Names)
+				if count == 0 {
+					count = 1
+				}
+				for k := 0; k < count; k++ {
+					result += " " + generateTypeNameByExp(field.Type)
+				}
+			}
 		} else {
 			result += " ("
-			for i, field := range n.Results.List {
-				if i > 0 {
-					result += ", "
+			first := true
+			for _, field := range n.Results.List {
+				count := len(field.Names)
+				if count == 0 {
+					count = 1
 				}
-				if len(field.Names) > 0 {
-					for j, name := range field.Names {
-						if j > 0 {
-							result += ", "
-						}
-						result += name.Name + " " + generateTypeNameByExp(field.Type)
+				for k := 0; k < count; k++ {
+					if !first {
+						result += ", "
 					}
-				} else {
 					result += generateTypeNameByExp(field.Type)
+					first = false
 				}
 			}
 			result += ")"

plugins/core/instrument/enhance_test.go

@@ -113,6 +113,77 @@ func TestGenerateTypeNameByExp_FuncType(t *testing.T) {
 			},
 			"func(context.Context, *primitive.SendResult, error)",
 		},
+		{
+			"func with named params ignores names",
+			&dst.FuncType{
+				Params: &dst.FieldList{List: []*dst.Field{
+					{Names: []*dst.Ident{dst.NewIdent("ctx")}, Type: &dst.SelectorExpr{X: dst.NewIdent("context"), Sel: dst.NewIdent("Context")}},
+					{Names: []*dst.Ident{dst.NewIdent("err")}, Type: dst.NewIdent("error")},
+				}},
+			},
+			"func(context.Context, error)",
+		},
+		{
+			"func with multi-name field expands types",
+			&dst.FuncType{
+				Params: &dst.FieldList{List: []*dst.Field{
+					{Names: []*dst.Ident{dst.NewIdent("a"), dst.NewIdent("b")}, Type: dst.NewIdent("int")},
+					{Names: []*dst.Ident{dst.NewIdent("s")}, Type: dst.NewIdent("string")},
+				}},
+			},
+			"func(int, int, string)",
+		},
+		{
+			"func with named single result ignores name",
+			&dst.FuncType{
+				Params: &dst.FieldList{List: []*dst.Field{
+					{Type: dst.NewIdent("int")},
+				}},
+				Results: &dst.FieldList{List: []*dst.Field{
+					{Names: []*dst.Ident{dst.NewIdent("err")}, Type: dst.NewIdent("error")},
+				}},
+			},
+			"func(int) error",
+		},
+		{
+			"func with named multiple results ignores names",
+			&dst.FuncType{
+				Params: &dst.FieldList{List: []*dst.Field{
+					{Type: dst.NewIdent("int")},
+				}},
+				Results: &dst.FieldList{List: []*dst.Field{
+					{Names: []*dst.Ident{dst.NewIdent("n")}, Type: dst.NewIdent("int")},
+					{Names: []*dst.Ident{dst.NewIdent("err")}, Type: dst.NewIdent("error")},
+				}},
+			},
+			"func(int) (int, error)",
+		},
+		{
+			"func with multi-name result field expands types",
+			&dst.FuncType{
+				Params: &dst.FieldList{List: []*dst.Field{
+					{Type: dst.NewIdent("string")},
+				}},
+				Results: &dst.FieldList{List: []*dst.Field{
+					{Names: []*dst.Ident{dst.NewIdent("x"), dst.NewIdent("y")}, Type: dst.NewIdent("int")},
+				}},
+			},
+			"func(string) (int, int)",
+		},
+		{
+			"func with named params and results from real code",
+			&dst.FuncType{
+				Params: &dst.FieldList{List: []*dst.Field{
+					{Names: []*dst.Ident{dst.NewIdent("ctx")}, Type: &dst.SelectorExpr{X: dst.NewIdent("context"), Sel: dst.NewIdent("Context")}},
+					{Names: []*dst.Ident{dst.NewIdent("req")}, Type: &dst.StarExpr{X: &dst.SelectorExpr{X: dst.NewIdent("http"), Sel: dst.NewIdent("Request")}}},
+				}},
+				Results: &dst.FieldList{List: []*dst.Field{
+					{Names: []*dst.Ident{dst.NewIdent("resp")}, Type: &dst.StarExpr{X: &dst.SelectorExpr{X: dst.NewIdent("http"), Sel: dst.NewIdent("Response")}}},
+					{Names: []*dst.Ident{dst.NewIdent("err")}, Type: dst.NewIdent("error")},
+				}},
+			},
+			"func(context.Context, *http.Request) (*http.Response, error)",
+		},
 	}
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {