element-web/test/editor/position-test.ts

/*
Copyright 2019 The Matrix.org Foundation C.I.C.

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

    http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/

import EditorModel from "../../src/editor/model";
import { createPartCreator } from "./mock";

function createRenderer() {
    const render = (c) => {
        render.caret = c;
        render.count += 1;
    };
    render.count = 0;
    render.caret = null;
    return render;
}

describe("editor/position", function () {
    it("move first position backward in empty model", function () {
        const model = new EditorModel([], createPartCreator(), createRenderer());
        const pos = model.positionForOffset(0, true);
        const pos2 = pos.backwardsWhile(model, () => true);
        expect(pos).toBe(pos2);
    });
    it("move first position forwards in empty model", function () {
        const model = new EditorModel([], createPartCreator(), createRenderer());
        const pos = model.positionForOffset(0, true);
        const pos2 = pos.forwardsWhile(model, () => true);
        expect(pos).toBe(pos2);
    });
    it("move forwards within one part", function () {
        const pc = createPartCreator();
        const model = new EditorModel([pc.plain("hello")], pc, createRenderer());
        const pos = model.positionForOffset(1);
        let n = 3;
        const pos2 = pos.forwardsWhile(model, () => {
            n -= 1;
            return n >= 0;
        });
        expect(pos2.index).toBe(0);
        expect(pos2.offset).toBe(4);
    });
    it("move forwards crossing to other part", function () {
        const pc = createPartCreator();
        const model = new EditorModel([pc.plain("hello"), pc.plain(" world")], pc, createRenderer());
        const pos = model.positionForOffset(4);
        let n = 3;
        const pos2 = pos.forwardsWhile(model, () => {
            n -= 1;
            return n >= 0;
        });
        expect(pos2.index).toBe(1);
        expect(pos2.offset).toBe(2);
    });
    it("move backwards within one part", function () {
        const pc = createPartCreator();
        const model = new EditorModel([pc.plain("hello")], pc, createRenderer());
        const pos = model.positionForOffset(4);
        let n = 3;
        const pos2 = pos.backwardsWhile(model, () => {
            n -= 1;
            return n >= 0;
        });
        expect(pos2.index).toBe(0);
        expect(pos2.offset).toBe(1);
    });
    it("move backwards crossing to other part", function () {
        const pc = createPartCreator();
        const model = new EditorModel([pc.plain("hello"), pc.plain(" world")], pc, createRenderer());
        const pos = model.positionForOffset(7);
        let n = 3;
        const pos2 = pos.backwardsWhile(model, () => {
            n -= 1;
            return n >= 0;
        });
        expect(pos2.index).toBe(0);
        expect(pos2.offset).toBe(4);
    });
});