undo_2 0.2.1

Undo and redo done the right-way.
Documentation 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83

#![allow(unused)]
use undo_2::{Action, Commands};

#[derive(Debug, Eq, PartialEq)]
enum Command {
    A,
    B,
    C,
    D,
}
use Action::*;
use Command::*;

#[test]
fn redo() {
    {
        let mut commands = Commands::new();

        commands.push(A); // A
        commands.push(B); // A B
        commands.undo(); // A
        commands.undo(); //
        commands.push(C); // C
        commands.undo(); //
        commands.undo(); // A B

        let v: Vec<_> = commands.redo().collect();
        assert_eq!(v, [(Undo, &B), (Undo, &A)]);

        let v: Vec<_> = commands.redo().collect();
        assert_eq!(v, [(Do, &C)]);
    }
    {
        let mut commands = Commands::new();

        commands.push(A); // A
        commands.push(B); // A B
        commands.undo(); // A
        commands.undo(); //
                         //
        commands.push(C); // C
                          //
        commands.undo(); //
        commands.undo(); // A B
        commands.undo(); // A
        commands.undo(); //

        commands.push(D); // D

        commands.undo(); //
        commands.undo(); // C
        commands.undo(); //
        commands.undo(); // A B

        let v: Vec<_> = commands.redo().collect();
        assert_eq!(v, [(Undo, &B), (Undo, &A)]);

        let v: Vec<_> = commands.redo().collect();
        assert_eq!(v, [(Do, &C)]);

        let v: Vec<_> = commands.redo().collect();
        assert_eq!(v, [(Undo, &C)]);

        let v: Vec<_> = commands.redo().collect();
        assert_eq!(v, [(Do, &D)]);

        let v: Vec<_> = commands.redo().collect();
        assert_eq!(v, []);
    }
}

#[test]
fn redo_all() {
    let mut commands = Commands::new();

    commands.push(A);
    commands.push(B);
    commands.undo();
    commands.undo();

    let v: Vec<_> = commands.redo_all().collect();
    assert_eq!(v, [(Do, &A), (Do, &Command::B)]);
}