Handle Op with index expressions (#18)

Author: ckaznocha

intrange.go

@@ -245,6 +245,8 @@ func findNExpr(expr ast.Expr) ast.Expr {
 		return e
 	case *ast.SelectorExpr:
 		return e
+	case *ast.IndexExpr:
+		return e
 	default:
 		return nil
 	}
@@ -293,7 +295,19 @@ func identEqual(a, b ast.Expr) bool {
 
 		return identEqual(aT.Sel, selectorB.Sel) && identEqual(aT.X, selectorB.X)
 	case *ast.IndexExpr:
+		indexB, ok := b.(*ast.IndexExpr)
+		if ok {
+			return identEqual(aT.X, indexB.X) && identEqual(aT.Index, indexB.Index)
+		}
+
 		return identEqual(aT.X, b)
+	case *ast.BasicLit:
+		litB, ok := b.(*ast.BasicLit)
+		if !ok {
+			return false
+		}
+
+		return aT.Value == litB.Value
 	default:
 		return false
 	}

testdata/main.go

@@ -198,3 +198,31 @@ func issue16(service protoreflect.ServiceDescriptor) {
 		print(i)
 	}
 }
+
+func opReEval_IndexExpressions_ArrayLike(n []int) {
+	for i := 0; i < n[0]; i++ { // want `for loop can be changed to use an integer range \(Go 1\.22\+\)`
+		print(i)
+	}
+
+	for i := 0; i < n[0]; i++ {
+		n[0]++
+	}
+
+	for i := 0; i < n[0]; i++ {
+		n[0] = 5
+	}
+}
+
+func opReEval_IndexExpressions_Map(n map[string]int) {
+	for i := 0; i < n["N"]; i++ { // want `for loop can be changed to use an integer range \(Go 1\.22\+\)`
+		print(i)
+	}
+
+	for i := 0; i < n["N"]; i++ {
+		n["N"]++
+	}
+
+	for i := 0; i < n["N"]; i++ {
+		n["N"] = 5
+	}
+}