Parse: allow trailing commas in array (not just object)

Author: sqs

parser_test.go

@@ -48,6 +48,7 @@ func TestParser(t *testing.T) {
 		"[]":                {want: "[]"},
 		"[ [], [ [] ]]":     {want: "[[],[[]]]"},
 		"[ 1, 2, 3 ]":       {want: "[1,2,3]"},
+		"[ 1, 5, ]":         {want: "[1,5]"},
 		`[ { "a": null } ]`: {want: `[{"a":null}]`},
 
 		// objects with errors
@@ -60,7 +61,6 @@ func TestParser(t *testing.T) {
 
 		// array with errors
 		"[,]":           {want: "[]", errors: true},
-		"[ 1, 5, ]":     {want: "[1,5]"},
 		"[ 1, 2, ]":     {options: &ParseOptions{TrailingCommas: false}, want: "[1,2]", errors: true},
 		"[ 1 2, 3]":     {want: "[1,2,3]", errors: true},
 		"[ ,1, 2, 3 ]":  {want: "[1,2,3]", errors: true},
@@ -93,6 +93,9 @@ func TestParser(t *testing.T) {
 		if test.errors && errors == nil {
 			t.Errorf("%s: got no parse errors, want parse errors", label)
 		}
+		if !test.errors && errors != nil {
+			t.Errorf("%s: got parse errors %v, want no parse errors", label, errors)
+		}
 		if string(output) != test.want {
 			t.Errorf("%s: got output %s, want %s", label, output, test.want)
 		}

visitor.go

@@ -260,6 +260,9 @@ func (w *walker) parseArray() bool {
 			}
 			w.onSeparator(',')
 			w.scanNext() // consume comma
+			if w.scanner.Token() == CloseBracketToken && w.options.TrailingCommas {
+				break
+			}
 		} else if needsComma {
 			w.handleError(CommaExpected, nil, nil)
 		}