overleaf/services/document-updater/test/unit/coffee/ShareJS/TextTransformTests.js

/*
 * decaffeinate suggestions:
 * DS101: Remove unnecessary use of Array.from
 * DS102: Remove unnecessary code created because of implicit returns
 * DS202: Simplify dynamic range loops
 * DS205: Consider reworking code to avoid use of IIFEs
 * Full docs: https://github.com/decaffeinate/decaffeinate/blob/master/docs/suggestions.md
 */
const text = require("../../../../app/js/sharejs/types/text");
require("chai").should();
const RangesTracker = require("../../../../app/js/RangesTracker");

describe("ShareJS text type", function() {
	beforeEach(function() {
		return this.t = "mock-thread-id";
	});
		
	describe("transform", function() {
		describe("insert / insert", function() {
			it("with an insert before", function() {
				const dest = [];
				text._tc(dest, { i: "foo", p: 9 }, { i: "bar", p: 3 });
				return dest.should.deep.equal([{ i: "foo", p: 12 }]);
		});

			it("with an insert after", function() {
				const dest = [];
				text._tc(dest, { i: "foo", p: 3 }, { i: "bar", p: 9 });
				return dest.should.deep.equal([{ i: "foo", p: 3 }]);
		});

			it("with an insert at the same place with side == 'right'", function() {
				const dest = [];
				text._tc(dest, { i: "foo", p: 3 }, { i: "bar", p: 3 }, 'right');
				return dest.should.deep.equal([{ i: "foo", p: 6 }]);
		});

			return it("with an insert at the same place with side == 'left'", function() {
				const dest = [];
				text._tc(dest, { i: "foo", p: 3 }, { i: "bar", p: 3 }, 'left');
				return dest.should.deep.equal([{ i: "foo", p: 3 }]);
		});
	});

		describe("insert / delete", function() {
			it("with a delete before", function() {
				const dest = [];
				text._tc(dest, { i: "foo", p: 9 }, { d: "bar", p: 3 });
				return dest.should.deep.equal([{ i: "foo", p: 6 }]);
		});

			it("with a delete after", function() {
				const dest = [];
				text._tc(dest, { i: "foo", p: 3 }, { d: "bar", p: 9 });
				return dest.should.deep.equal([{ i: "foo", p: 3 }]);
		});

			it("with a delete at the same place with side == 'right'", function() {
				const dest = [];
				text._tc(dest, { i: "foo", p: 3 }, { d: "bar", p: 3 }, 'right');
				return dest.should.deep.equal([{ i: "foo", p: 3 }]);
		});

			return it("with a delete at the same place with side == 'left'", function() {
				const dest = [];
				
				text._tc(dest, { i: "foo", p: 3 }, { d: "bar", p: 3 }, 'left');
				return dest.should.deep.equal([{ i: "foo", p: 3 }]);
		});
	});

		describe("delete / insert", function() {
			it("with an insert before", function() {
				const dest = [];
				text._tc(dest, { d: "foo", p: 9 }, { i: "bar", p: 3 });
				return dest.should.deep.equal([{ d: "foo", p: 12 }]);
		});

			it("with an insert after", function() {
				const dest = [];
				text._tc(dest, { d: "foo", p: 3 }, { i: "bar", p: 9 });
				return dest.should.deep.equal([{ d: "foo", p: 3 }]);
		});

			it("with an insert at the same place with side == 'right'", function() {
				const dest = [];
				text._tc(dest, { d: "foo", p: 3 }, { i: "bar", p: 3 }, 'right');
				return dest.should.deep.equal([{ d: "foo", p: 6 }]);
		});

			it("with an insert at the same place with side == 'left'", function() {
				const dest = [];
				text._tc(dest, { d: "foo", p: 3 }, { i: "bar", p: 3 }, 'left');
				return dest.should.deep.equal([{ d: "foo", p: 6 }]);
		});
			
			return it("with a delete that overlaps the insert location", function() {
				const dest = [];
				text._tc(dest, { d: "foo", p: 3 }, { i: "bar", p: 4 });
				return dest.should.deep.equal([{ d: "f", p: 3 }, { d: "oo", p: 6 }]);
		});
	});
				

		describe("delete / delete", function() {
			it("with a delete before", function() {
				const dest = [];
				text._tc(dest, { d: "foo", p: 9 }, { d: "bar", p: 3 });
				return dest.should.deep.equal([{ d: "foo", p: 6 }]);
		});

			it("with a delete after", function() {
				const dest = [];
				text._tc(dest, { d: "foo", p: 3 }, { d: "bar", p: 9 });
				return dest.should.deep.equal([{ d: "foo", p: 3 }]);
		});

			it("with deleting the same content", function() {
				const dest = [];
				text._tc(dest, { d: "foo", p: 3 }, { d: "foo", p: 3 }, 'right');
				return dest.should.deep.equal([]);
		});

			it("with the delete overlapping before", function() {
				const dest = [];
				text._tc(dest, { d: "foobar", p: 3 }, { d: "abcfoo", p: 0 }, 'right');
				return dest.should.deep.equal([{ d: "bar", p: 0 }]);
		});

			it("with the delete overlapping after", function() {
				const dest = [];
				text._tc(dest, { d: "abcfoo", p: 3 }, { d: "foobar", p: 6 });
				return dest.should.deep.equal([{ d: "abc", p: 3 }]);
		});

			it("with the delete overlapping the whole delete", function() {
				const dest = [];
				text._tc(dest, { d: "abcfoo123", p: 3 }, { d: "foo", p: 6 });
				return dest.should.deep.equal([{ d: "abc123", p: 3 }]);
		});

			return it("with the delete inside the whole delete", function() {
				const dest = [];
				text._tc(dest, { d: "foo", p: 6 }, { d: "abcfoo123", p: 3 });
				return dest.should.deep.equal([]);
		});
	});
	
		describe("comment / insert", function() {
			it("with an insert before", function() {
				const dest = [];
				text._tc(dest, { c: "foo", p: 9, t: this.t }, { i: "bar", p: 3 });
				return dest.should.deep.equal([{ c: "foo", p: 12, t: this.t }]);
		});

			it("with an insert after", function() {
				const dest = [];
				text._tc(dest, { c: "foo", p: 3, t: this.t }, { i: "bar", p: 9 });
				return dest.should.deep.equal([{ c: "foo", p: 3, t: this.t }]);
		});

			it("with an insert at the left edge", function() {
				const dest = [];
				text._tc(dest, { c: "foo", p: 3, t: this.t }, { i: "bar", p: 3 });
				// RangesTracker doesn't inject inserts into comments on edges, so neither should we
				return dest.should.deep.equal([{ c: "foo", p: 6, t: this.t }]);
		});

			it("with an insert at the right edge", function() {
				const dest = [];
				text._tc(dest, { c: "foo", p: 3, t: this.t }, { i: "bar", p: 6 });
				// RangesTracker doesn't inject inserts into comments on edges, so neither should we
				return dest.should.deep.equal([{ c: "foo", p: 3, t: this.t }]);
		});

			return it("with an insert in the middle", function() {
				const dest = [];
				text._tc(dest, { c: "foo", p: 3, t: this.t }, { i: "bar", p: 5 });
				return dest.should.deep.equal([{ c: "fobaro", p: 3, t: this.t }]);
		});
	});
	
		describe("comment / delete", function() {
			it("with a delete before", function() {
				const dest = [];
				text._tc(dest, { c: "foo", p: 9, t: this.t }, { d: "bar", p: 3 });
				return dest.should.deep.equal([{ c: "foo", p: 6, t: this.t }]);
		});

			it("with a delete after", function() {
				const dest = [];
				text._tc(dest, { c: "foo", p: 3, t: this.t }, { i: "bar", p: 9 });
				return dest.should.deep.equal([{ c: "foo", p: 3, t: this.t }]);
		});

			it("with a delete overlapping the comment content before", function() {
				const dest = [];
				text._tc(dest, { c: "foobar", p: 6, t: this.t }, { d: "123foo", p: 3 });
				return dest.should.deep.equal([{ c: "bar", p: 3, t: this.t }]);
		});

			it("with a delete overlapping the comment content after", function() {
				const dest = [];
				text._tc(dest, { c: "foobar", p: 6, t: this.t }, { d: "bar123", p: 9 });
				return dest.should.deep.equal([{ c: "foo", p: 6, t: this.t }]);
		});

			it("with a delete overlapping the comment content in the middle", function() {
				const dest = [];
				text._tc(dest, { c: "foo123bar", p: 6, t: this.t }, { d: "123", p: 9 });
				return dest.should.deep.equal([{ c: "foobar", p: 6, t: this.t }]);
		});

			return it("with a delete overlapping the whole comment", function() {
				const dest = [];
				text._tc(dest, { c: "foo", p: 6, t: this.t }, { d: "123foo456", p: 3 });
				return dest.should.deep.equal([{ c: "", p: 3, t: this.t }]);
		});
	});
	
		describe("comment / insert", () => it("should not do anything", function() {
            const dest = [];
            text._tc(dest, { i: "foo", p: 6 }, { c: "bar", p: 3 });
            return dest.should.deep.equal([{ i: "foo", p: 6 }]);
    }));
	
		describe("comment / delete", () => it("should not do anything", function() {
            const dest = [];
            text._tc(dest, { d: "foo", p: 6 }, { c: "bar", p: 3 });
            return dest.should.deep.equal([{ d: "foo", p: 6 }]);
    }));
	
		return describe("comment / comment", () => it("should not do anything", function() {
            const dest = [];
            text._tc(dest, { c: "foo", p: 6 }, { c: "bar", p: 3 });
            return dest.should.deep.equal([{ c: "foo", p: 6 }]);
    }));
});

	describe("apply", function() {
		it("should apply an insert", () => text.apply("foo", [{ i: "bar", p: 2 }]).should.equal("fobaro"));

		it("should apply a delete", () => text.apply("foo123bar", [{ d: "123", p: 3 }]).should.equal("foobar"));

		it("should do nothing with a comment", () => text.apply("foo123bar", [{ c: "123", p: 3 }]).should.equal("foo123bar"));
		
		it("should throw an error when deleted content does not match", () => ((() => text.apply("foo123bar", [{ d: "456", p: 3 }]))).should.throw(Error));
		
		return it("should throw an error when comment content does not match", () => ((() => text.apply("foo123bar", [{ c: "456", p: 3 }]))).should.throw(Error));
	});
	
	return describe("applying ops and comments in different orders", () => it("should not matter which op or comment is applied first", function() {
        let length, p;
        let asc, end;
        let asc1, end1;
        let asc3, end3;
        const transform = function(op1, op2, side) {
            const d = [];
            text._tc(d, op1, op2, side);
            return d;
        };
        
        const applySnapshot = (snapshot, op) => text.apply(snapshot, op);
        
        const applyRanges = function(rangesTracker, ops) {
            for (let op of Array.from(ops)) {
                rangesTracker.applyOp(op, {});
            }
            return rangesTracker;
        };
        
        const commentsEqual = function(comments1, comments2) {
            if (comments1.length !== comments2.length) { return false; }
            comments1.sort(function(a,b) {
                if ((a.offset - b.offset) === 0) {
                    return a.length - b.length;
                } else {
                    return a.offset - b.offset;
                }
            });
            comments2.sort(function(a,b) {
                if ((a.offset - b.offset) === 0) {
                    return a.length - b.length;
                } else {
                    return a.offset - b.offset;
                }
            });
            for (let i = 0; i < comments1.length; i++) {
                const comment1 = comments1[i];
                const comment2 = comments2[i];
                if ((comment1.offset !== comment2.offset) || (comment1.length !== comment2.length)) {
                    return false;
                }
            }
            return true;
        };
        
        const SNAPSHOT = "123";
        
        const OPS = [];
        // Insert ops
        for (p = 0, end = SNAPSHOT.length, asc = 0 <= end; asc ? p <= end : p >= end; asc ? p++ : p--) {
            OPS.push({i: "a", p});
            OPS.push({i: "bc", p});
        }
        for (p = 0, end1 = SNAPSHOT.length-1, asc1 = 0 <= end1; asc1 ? p <= end1 : p >= end1; asc1 ? p++ : p--) {
            var asc2, end2;
            for (length = 1, end2 = SNAPSHOT.length - p, asc2 = 1 <= end2; asc2 ? length <= end2 : length >= end2; asc2 ? length++ : length--) {
                OPS.push({d: SNAPSHOT.slice(p, p+length), p});
            }
        }
        for (p = 0, end3 = SNAPSHOT.length-1, asc3 = 0 <= end3; asc3 ? p <= end3 : p >= end3; asc3 ? p++ : p--) {
            var asc4, end4;
            for (length = 1, end4 = SNAPSHOT.length - p, asc4 = 1 <= end4; asc4 ? length <= end4 : length >= end4; asc4 ? length++ : length--) {
                OPS.push({c: SNAPSHOT.slice(p, p+length), p, t: this.t});
            }
        }

        return (() => {
            const result = [];
            for (var op1 of Array.from(OPS)) {
                result.push((() => {
                    const result1 = [];
                    for (let op2 of Array.from(OPS)) {
                        const op1_t = transform(op1, op2, "left");
                        const op2_t = transform(op2, op1, "right");
                
                        const rt12 = new RangesTracker();
                        const snapshot12 = applySnapshot(applySnapshot(SNAPSHOT, [op1]), op2_t);
                        applyRanges(rt12, [op1]);
                        applyRanges(rt12, op2_t);
                
                        const rt21 = new RangesTracker();
                        const snapshot21 = applySnapshot(applySnapshot(SNAPSHOT, [op2]), op1_t);
                        applyRanges(rt21, [op2]);
                        applyRanges(rt21, op1_t);
                
                        if (snapshot12 !== snapshot21) {
                            console.error({op1, op2, op1_t, op2_t, snapshot12, snapshot21}, "Ops are not consistent");
                            throw new Error("OT is inconsistent");
                        }
                
                        if (!commentsEqual(rt12.comments, rt21.comments)) {
                            console.log(rt12.comments);
                            console.log(rt21.comments);
                            console.error({op1, op2, op1_t, op2_t, rt12_comments: rt12.comments, rt21_comments: rt21.comments}, "Comments are not consistent");
                            throw new Error("OT is inconsistent");
                        } else {
                            result1.push(undefined);
                        }
                    }
                    return result1;
                })());
            }
            return result;
        })();
    }));
});