Add more tests for filter_map optimization

Author: antonmedv

expr_test.go

@@ -2764,7 +2764,7 @@ func TestExpr_env_types_map_error(t *testing.T) {
 	require.Error(t, err)
 }
 
-func TestIssue758_FilterMapIndex(t *testing.T) {
+func TestIssue758_filter_map_index(t *testing.T) {
 	env := map[string]interface{}{}
 
 	exprStr := `

optimizer/filter_map_test.go

@@ -72,3 +72,43 @@ func TestOptimize_filter_map_with_index_pointer(t *testing.T) {
 
 	assert.Equal(t, Dump(expected), Dump(tree.Node))
 }
+
+func TestOptimize_filter_map_with_index_pointer_with_index_pointer_in_first_argument(t *testing.T) {
+	tree, err := parser.Parse(`1..2 | map(map(filter([#index], true), 42))`)
+	require.NoError(t, err)
+
+	err = optimizer.Optimize(&tree.Node, nil)
+	require.NoError(t, err)
+
+	expected := &BuiltinNode{
+		Name: "map",
+		Arguments: []Node{
+			&BinaryNode{
+				Operator: "..",
+				Left:     &IntegerNode{Value: 1},
+				Right:    &IntegerNode{Value: 2},
+			},
+			&PredicateNode{
+				Node: &BuiltinNode{
+					Name: "filter",
+					Arguments: []Node{
+						&ArrayNode{
+							Nodes: []Node{
+								&PointerNode{Name: "index"},
+							},
+						},
+						&PredicateNode{
+							Node: &BoolNode{Value: true},
+						},
+					},
+					Throws: false,
+					Map:    &IntegerNode{Value: 42},
+				},
+			},
+		},
+		Throws: false,
+		Map:    nil,
+	}
+
+	assert.Equal(t, Dump(expected), Dump(tree.Node))
+}