Added list:add

ucl/builtins/lists.go

@@ -0,0 +1,35 @@
+package builtins
+
+import (
+	"context"
+	"ucl.lmika.dev/ucl"
+)
+
+func Lists() ucl.Module {
+	return ucl.Module{
+		Name: "lists",
+		Builtins: map[string]ucl.BuiltinHandler{
+			"add": listAdd,
+		},
+	}
+}
+
+func listAdd(ctx context.Context, args ucl.CallArgs) (any, error) {
+	var target ucl.ModListable
+
+	if err := args.Bind(&target); err != nil {
+		return nil, err
+	}
+
+	for args.NArgs() > 0 {
+		var obj ucl.Object
+		if err := args.Bind(&obj); err != nil {
+			return nil, err
+		}
+		if err := target.Insert(-1, obj); err != nil {
+			return nil, err
+		}
+	}
+
+	return target, nil
+}

ucl/builtins/lists_test.go

@@ -0,0 +1,37 @@
+package builtins_test
+
+import (
+	"context"
+	"github.com/stretchr/testify/assert"
+	"testing"
+	"ucl.lmika.dev/ucl"
+	"ucl.lmika.dev/ucl/builtins"
+)
+
+func TestLists_Add(t *testing.T) {
+	tests := []struct {
+		desc    string
+		eval    string
+		want    any
+		wantErr bool
+	}{
+		{desc: "list add 1", eval: `lists:add [1 2 3] 4`, want: []any{1, 2, 3, 4}},
+		{desc: "list add 2", eval: `lists:add [1 2 3] 4 5`, want: []any{1, 2, 3, 4, 5}},
+		{desc: "list add 3", eval: `lists:add [1 2 3]`, want: []any{1, 2, 3}},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.desc, func(t *testing.T) {
+			inst := ucl.New(
+				ucl.WithModule(builtins.Lists()),
+			)
+			res, err := inst.Eval(context.Background(), tt.eval)
+			if tt.wantErr {
+				assert.Error(t, err)
+			} else {
+				assert.NoError(t, err)
+				assert.Equal(t, tt.want, res)
+			}
+		})
+	}
+}