AppFlowy/frontend/app_flowy/packages/flowy_editor/test/delta_test.dart

import 'package:flutter_test/flutter_test.dart';
import 'package:flowy_editor/src/document/text_delta.dart';

void main() {
  group('compose', () {
    test('test delta', () {
      final delta = Delta(<TextOperation>[
        TextInsert('Gandalf', {
          'bold': true,
        }),
        TextInsert(' the '),
        TextInsert('Grey', {
          'color': '#ccc',
        })
      ]);

      final death = Delta()
        ..retain(12)
        ..insert("White", {
          'color': '#fff',
        })
        ..delete(4);

      final restores = delta.compose(death);
      expect(restores.toList(), <TextOperation>[
        TextInsert('Gandalf', {'bold': true}),
        TextInsert(' the '),
        TextInsert('White', {'color': '#fff'}),
      ]);
    });
    test('compose()', () {
      final a = Delta()..insert('A');
      final b = Delta()..insert('B');
      final expected = Delta()
        ..insert('B')
        ..insert('A');
      expect(a.compose(b), expected);
    });
    test('insert + retain', () {
      final a = Delta()..insert('A');
      final b = Delta()
        ..retain(1, {
          'bold': true,
          'color': 'red',
        });
      final expected = Delta()
        ..insert('A', {
          'bold': true,
          'color': 'red',
        });
      expect(a.compose(b), expected);
    });
    test('insert + delete', () {
      final a = Delta()..insert('A');
      final b = Delta()..delete(1);
      final expected = Delta();
      expect(a.compose(b), expected);
    });
    test('delete + insert', () {
      final a = Delta()..delete(1);
      final b = Delta()..insert('B');
      final expected = Delta()
        ..insert('B')
        ..delete(1);
      expect(a.compose(b), expected);
    });
    test('delete + retain', () {
      final a = Delta()..delete(1);
      final b = Delta()
        ..retain(1, {
          'bold': true,
          'color': 'red',
        });
      final expected = Delta()
        ..delete(1)
        ..retain(1, {
          'bold': true,
          'color': 'red',
        });
      expect(a.compose(b), expected);
    });
    test('delete + delete', () {
      final a = Delta()..delete(1);
      final b = Delta()..delete(1);
      final expected = Delta()..delete(2);
      expect(a.compose(b), expected);
    });
    test('retain + insert', () {
      final a = Delta()..retain(1, {'color': 'blue'});
      final b = Delta()..insert('B');
      final expected = Delta()
        ..insert('B')
        ..retain(1, {
          'color': 'blue',
        });
      expect(a.compose(b), expected);
    });
    test('retain + retain', () {
      final a = Delta()
        ..retain(1, {
          'color': 'blue',
        });
      final b = Delta()
        ..retain(1, {
          'bold': true,
          'color': 'red',
        });
      final expected = Delta()
        ..retain(1, {
          'bold': true,
          'color': 'red',
        });
      expect(a.compose(b), expected);
    });
    test('retain + delete', () {
      final a = Delta()
        ..retain(1, {
          'color': 'blue',
        });
      final b = Delta()..delete(1);
      final expected = Delta()..delete(1);
      expect(a.compose(b), expected);
    });
    test('insert in middle of text', () {
      final a = Delta()..insert('Hello');
      final b = Delta()
        ..retain(3)
        ..insert('X');
      final expected = Delta()..insert('HelXlo');
      expect(a.compose(b), expected);
    });
    test('insert and delete ordering', () {
      final a = Delta()..insert('Hello');
      final b = Delta()..insert('Hello');
      final insertFirst = Delta()
        ..retain(3)
        ..insert('X')
        ..delete(1);
      final deleteFirst = Delta()
        ..retain(3)
        ..delete(1)
        ..insert('X');
      final expected = Delta()..insert('HelXo');
      expect(a.compose(insertFirst), expected);
      expect(b.compose(deleteFirst), expected);
    });
    test('delete entire text', () {
      final a = Delta()
        ..retain(4)
        ..insert('Hello');
      final b = Delta()..delete(9);
      final expected = Delta()..delete(4);
      expect(a.compose(b), expected);
    });
    test('retain more than length of text', () {
      final a = Delta()..insert('Hello');
      final b = Delta()..retain(10);
      final expected = Delta()..insert('Hello');
      expect(a.compose(b), expected);
    });
    test('retain start optimization', () {
      final a = Delta()
        ..insert('A', {'bold': true})
        ..insert('B')
        ..insert('C', {'bold': true})
        ..delete(1);
      final b = Delta()
        ..retain(3)
        ..insert('D');
      final expected = Delta()
        ..insert('A', {'bold': true})
        ..insert('B')
        ..insert('C', {'bold': true})
        ..insert('D')
        ..delete(1);
      expect(a.compose(b), expected);
    });
    test('retain end optimization', () {
      final a = Delta()
        ..insert('A', {'bold': true})
        ..insert('B')
        ..insert('C', {'bold': true});
      final b = Delta()..delete(1);
      final expected = Delta()
        ..insert('B')
        ..insert('C', {'bold': true});
      expect(a.compose(b), expected);
    });
    test('retain end optimization join', () {
      final a = Delta()
        ..insert('A', {'bold': true})
        ..insert('B')
        ..insert('C', {'bold': true})
        ..insert('D')
        ..insert('E', {'bold': true})
        ..insert('F');
      final b = Delta()
        ..retain(1)
        ..delete(1);
      final expected = Delta()
        ..insert('AC', {'bold': true})
        ..insert('D')
        ..insert('E', {'bold': true})
        ..insert('F');
      expect(a.compose(b), expected);
    });
  });
  group('invert', () {
    test('insert', () {
      final delta = Delta()
        ..retain(2)
        ..insert('A');
      final base = Delta()..insert('12346');
      final expected = Delta()
        ..retain(2)
        ..delete(1);
      final inverted = delta.invert(base);
      expect(expected, inverted);
      expect(base.compose(delta).compose(inverted), base);
    });
    test('delete', () {
      final delta = Delta()
        ..retain(2)
        ..delete(3);
      final base = Delta()..insert('123456');
      final expected = Delta()
        ..retain(2)
        ..insert('345');
      final inverted = delta.invert(base);
      expect(expected, inverted);
      expect(base.compose(delta).compose(inverted), base);
    });
    // test('retain', () {
    //   final delta = Delta().retain(2).retain(3, {'bold': true});
    //   final base = Delta().insert('123456');
    //   final expected = Delta().retain(2).retain(3, {'bold': null});
    //   final inverted = delta.invert(base);
    //   expect(expected, inverted);
    //   expect(base.compose(delta).compose(inverted), base);
    // });
  });
  group('json', () {
    test('toJson()', () {
      final delta = Delta()
        ..retain(2)
        ..insert('A')
        ..delete(3);
      expect(delta.toJson(), [
        {'retain': 2},
        {'insert': 'A'},
        {'delete': 3}
      ]);
    });
    test('attributes', () {
      final delta = Delta()
        ..retain(2, {'bold': true})
        ..insert('A', {'italic': true});
      expect(delta.toJson(), [
        {
          'retain': 2,
          'attributes': {'bold': true},
        },
        {
          'insert': 'A',
          'attributes': {'italic': true},
        },
      ]);
    });
    test('fromJson()', () {
      final delta = Delta.fromJson([
        {'retain': 2},
        {'insert': 'A'},
        {'delete': 3},
      ]);
      final expected = Delta()
        ..retain(2)
        ..insert('A')
        ..delete(3);
      expect(delta, expected);
    });
  });
  group('runes', () {
    test("stringIndexes", () {
      final indexes = stringIndexes('😊');
      expect(indexes[0], 0);
      expect(indexes[1], 0);
    });
    test("next rune 1", () {
      final delta = Delta()..insert('😊');
      expect(delta.nextRunePosition(0), 2);
    });
    test("next rune 2", () {
      final delta = Delta()..insert('😊a');
      expect(delta.nextRunePosition(0), 2);
    });
    test("next rune 3", () {
      final delta = Delta()..insert('😊陈');
      expect(delta.nextRunePosition(2), 3);
    });
    test("prev rune 1", () {
      final delta = Delta()..insert('😊陈');
      expect(delta.prevRunePosition(2), 0);
    });
    test("prev rune 2", () {
      final delta = Delta()..insert('😊');
      expect(delta.prevRunePosition(2), 0);
    });
    test("prev rune 3", () {
      final delta = Delta()..insert('😊');
      expect(delta.prevRunePosition(0), -1);
    });
  });
}