Fix BigInt remote object parsing

common/remote_object.go

@@ -5,6 +5,7 @@ import (
 	"encoding/json"
 	"fmt"
 	"math"
+	"regexp"
 	"strconv"
 	"strings"
 
@@ -15,6 +16,8 @@ import (
 	"github.com/dop251/goja"
 )
 
+var bigIntRegex = regexp.MustCompile("^[0-9]*n$")
+
 type objectOverflowError struct{}
 
 // Error returns the description of the overflow error.
@@ -164,11 +167,21 @@ func parseExceptionDetails(exc *cdpruntime.ExceptionDetails) string {
 // parseRemoteObject is to be used by callers that require the string value
 // to be parsed to a Go type.
 func parseRemoteObject(obj *cdpruntime.RemoteObject) (any, error) {
-	if obj.UnserializableValue == "" {
+	uv := obj.UnserializableValue
+
+	if uv == "" {
 		return parseRemoteObjectValue(obj.Type, obj.Subtype, string(obj.Value), obj.Preview)
 	}
 
-	switch obj.UnserializableValue.String() {
+	if bigIntRegex.Match([]byte(uv)) {
+		n, err := strconv.ParseInt(strings.ReplaceAll(uv.String(), "n", ""), 10, 64)
+		if err != nil {
+			return nil, BigIntParseError{err}
+		}
+		return n, nil
+	}
+
+	switch uv.String() {
 	case "-0": // To handle +0 divided by negative number
 		return math.Float64frombits(0 | (1 << 63)), nil
 	case "NaN":
@@ -182,7 +195,7 @@ func parseRemoteObject(obj *cdpruntime.RemoteObject) (any, error) {
 	// We should never get here, as previous switch statement should
 	// be exhaustive and contain all possible unserializable values.
 	// See: https://chromedevtools.github.io/devtools-protocol/tot/Runtime/#type-UnserializableValue
-	return nil, UnserializableValueError{obj.UnserializableValue}
+	return nil, UnserializableValueError{uv}
 }
 
 func valueFromRemoteObject(ctx context.Context, robj *cdpruntime.RemoteObject) (goja.Value, error) {

tests/remote_obj_test.go

@@ -5,6 +5,7 @@ import (
 	"testing"
 	"time"
 
+	"github.com/dop251/goja"
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
 
@@ -106,3 +107,86 @@ func TestConsoleLogParse(t *testing.T) {
 		})
 	}
 }
+
+func TestEvalRemoteObjectParse(t *testing.T) {
+	t.Parallel()
+
+	tests := []struct {
+		name string
+		eval string
+		want any
+	}{
+		{
+			name: "number", eval: "1", want: 1,
+		},
+		{
+			name: "string", eval: `"some string"`, want: "some string",
+		},
+		{
+			name: "bool", eval: "true", want: true,
+		},
+		{
+			name: "empty_array", eval: "[]", want: []any{},
+		},
+		{
+			name: "empty_object", eval: "{}", want: goja.Undefined(),
+		},
+		{
+			name: "filled_object", eval: `{return {foo:"bar"};}`, want: map[string]any{"foo": "bar"},
+		},
+		{
+			name: "filled_array", eval: `{return ["foo","bar"];}`, want: []any{0: "foo", 1: "bar"},
+		},
+		{
+			name: "filled_array", eval: `() => true`, want: `function()`,
+		},
+		{
+			name: "empty", eval: "", want: "",
+		},
+		{
+			name: "null", eval: "null", want: "null",
+		},
+		{
+			name: "undefined", eval: "undefined", want: goja.Undefined(),
+		},
+		{
+			name: "bigint", eval: `BigInt("2")`, want: 2,
+		},
+		{
+			name: "unwrapped_bigint", eval: "3n", want: 3,
+		},
+		{
+			name: "float", eval: "3.14", want: 3.14,
+		},
+		{
+			name: "scientific_notation", eval: "123e-5", want: 0.00123,
+		},
+		// TODO:
+		// {
+		// 	// This test is ignored until https://github.com/grafana/xk6-browser/issues/1132
+		// 	// has been resolved.
+		// 	name: "partially_parsed",
+		// 	eval:  "window",
+		// 	want: `{"document":"#document","location":"Location","name":"","self":"Window","window":"Window"}`,
+		// },
+	}
+
+	for _, tt := range tests {
+		tt := tt
+		t.Run(tt.name, func(t *testing.T) {
+			t.Parallel()
+
+			tb := newTestBrowser(t, withFileServer())
+			p := tb.NewPage(nil)
+
+			var got any
+			if tt.eval == "" {
+				got = p.Evaluate(tb.toGojaValue(`() => ""`))
+			} else {
+				got = p.Evaluate(tb.toGojaValue(fmt.Sprintf("() => %s", tt.eval)))
+			}
+
+			assert.Equal(t, tb.toGojaValue(tt.want), got)
+		})
+	}
+}