support method receivers with type parameters for Go 1.18

analyze.go

@@ -138,15 +138,3 @@ func funcName(fn *ast.FuncDecl) string {
 	}
 	return fn.Name.Name
 }
-
-// recvString returns a string representation of recv of the
-// form "T", "*T", or "BADRECV" (if not a proper receiver type).
-func recvString(recv ast.Expr) string {
-	switch t := recv.(type) {
-	case *ast.Ident:
-		return t.Name
-	case *ast.StarExpr:
-		return "*" + recvString(t.X)
-	}
-	return "BADRECV"
-}

go.mod

@@ -1,3 +1,3 @@
 module github.com/fzipp/gocyclo
 
-go 1.16
+go 1.18

recv.go

@@ -0,0 +1,26 @@
+// Copyright 2021 Frederik Zipp. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build go1.18
+// +build go1.18
+
+package gocyclo
+
+import "go/ast"
+
+// recvString returns a string representation of recv of the
+// form "T", "*T", or "BADRECV" (if not a proper receiver type).
+func recvString(recv ast.Expr) string {
+	switch t := recv.(type) {
+	case *ast.Ident:
+		return t.Name
+	case *ast.StarExpr:
+		return "*" + recvString(t.X)
+	case *ast.IndexExpr:
+		return recvString(t.X)
+	case *ast.IndexListExpr:
+		return recvString(t.X)
+	}
+	return "BADRECV"
+}

recv_pre118.go

@@ -0,0 +1,24 @@
+// Copyright 2021 Frederik Zipp. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build !go1.18
+// +build !go1.18
+
+package gocyclo
+
+import "go/ast"
+
+// recvString returns a string representation of recv of the
+// form "T", "*T", or "BADRECV" (if not a proper receiver type).
+func recvString(recv ast.Expr) string {
+	switch t := recv.(type) {
+	case *ast.Ident:
+		return t.Name
+	case *ast.StarExpr:
+		return "*" + recvString(t.X)
+	case *ast.IndexExpr:
+		return recvString(t.X)
+	}
+	return "BADRECV"
+}