semver-diff 0.1.1

Find the release-type difference between two semantic versions (major/minor/patch and their prerelease variants). A faithful Rust port of node-semver's diff.
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
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143

//! End-to-end behavioral spec for the public `semver-diff` API.
//!
//! Expected values are cross-checked against node-semver's `diff()`.

use semver::Version;
use semver_diff::{diff, diff_str, Difference};

fn v(s: &str) -> Version {
    Version::parse(s).unwrap()
}

// ---------------------------------------------------------------------------
// Release-level changes (no prerelease)
// ---------------------------------------------------------------------------

#[test]
fn release_level_diffs() {
    assert_eq!(diff(&v("1.0.0"), &v("1.0.1")), Some(Difference::Patch));
    assert_eq!(diff(&v("1.0.0"), &v("1.1.0")), Some(Difference::Minor));
    assert_eq!(diff(&v("1.0.0"), &v("2.0.0")), Some(Difference::Major));
    assert_eq!(diff(&v("1.2.3"), &v("1.2.4")), Some(Difference::Patch));
}

#[test]
fn equal_versions_are_none() {
    assert_eq!(diff(&v("1.2.3"), &v("1.2.3")), None);
    // Build metadata is ignored, just like semver comparison.
    assert_eq!(diff(&v("1.2.3+build.1"), &v("1.2.3+build.2")), None);
}

#[test]
fn diff_is_symmetric() {
    let pairs = [
        ("1.0.0", "2.3.4"),
        ("1.0.0-alpha", "1.0.0"),
        ("1.0.0", "1.1.0-rc.1"),
        ("1.2.0-alpha", "1.2.0"),
    ];
    for (a, b) in pairs {
        assert_eq!(diff(&v(a), &v(b)), diff(&v(b), &v(a)), "{a} vs {b}");
    }
}

// ---------------------------------------------------------------------------
// Going TO a prerelease → the `pre*` variants
// ---------------------------------------------------------------------------

#[test]
fn changes_to_a_prerelease() {
    assert_eq!(
        diff(&v("1.0.0"), &v("2.0.0-pre")),
        Some(Difference::PreMajor)
    );
    assert_eq!(
        diff(&v("1.0.0"), &v("1.1.0-pre")),
        Some(Difference::PreMinor)
    );
    assert_eq!(
        diff(&v("1.0.0"), &v("1.0.1-pre")),
        Some(Difference::PrePatch)
    );
    // same main version, both prereleases that differ → prerelease
    assert_eq!(
        diff(&v("1.0.0-alpha"), &v("1.0.0-beta")),
        Some(Difference::PreRelease)
    );
    assert_eq!(
        diff(&v("1.0.0-alpha.1"), &v("1.0.0-alpha.2")),
        Some(Difference::PreRelease)
    );
}

// ---------------------------------------------------------------------------
// Releasing FROM a prerelease (node-semver's quirky branch)
// ---------------------------------------------------------------------------

#[test]
fn releasing_from_a_prerelease() {
    // X.0.0-pre → X.0.0 is a major release
    assert_eq!(
        diff(&v("1.0.0-alpha"), &v("1.0.0")),
        Some(Difference::Major)
    );
    // X.Y.0-pre → X.Y.0 is a minor release
    assert_eq!(
        diff(&v("1.2.0-alpha"), &v("1.2.0")),
        Some(Difference::Minor)
    );
    // X.Y.Z-pre → X.Y.Z is a patch release
    assert_eq!(
        diff(&v("1.2.3-alpha"), &v("1.2.3")),
        Some(Difference::Patch)
    );
}

// Regression: when the MAIN version also changes, a prerelease→release diff must
// fall through to the standard comparison (matches live node-semver 7.7.2).
#[test]
fn releasing_from_a_prerelease_with_changed_main() {
    assert_eq!(diff(&v("1.2.3-pre"), &v("2.3.5")), Some(Difference::Major));
    assert_eq!(diff(&v("1.5.0-pre"), &v("2.3.0")), Some(Difference::Major));
    assert_eq!(diff(&v("1.2.0-pre"), &v("1.3.5")), Some(Difference::Minor));
    assert_eq!(diff(&v("1.0.5-pre"), &v("1.2.3")), Some(Difference::Minor));
    assert_eq!(diff(&v("0.0.1-0"), &v("1.0.1")), Some(Difference::Major));
    assert_eq!(diff(&v("0.0.1-0"), &v("1.1.0")), Some(Difference::Major));
    assert_eq!(diff(&v("0.0.1-0"), &v("0.1.1")), Some(Difference::Minor));
    assert_eq!(diff(&v("0.1.3-pre"), &v("1.2.0")), Some(Difference::Major));
    assert_eq!(diff(&v("0.1.0-pre"), &v("0.2.5")), Some(Difference::Minor));
}

// ---------------------------------------------------------------------------
// Difference helpers + string form (matches node-semver)
// ---------------------------------------------------------------------------

#[test]
fn difference_as_str() {
    assert_eq!(Difference::Major.as_str(), "major");
    assert_eq!(Difference::PreMajor.as_str(), "premajor");
    assert_eq!(Difference::Minor.as_str(), "minor");
    assert_eq!(Difference::PreMinor.as_str(), "preminor");
    assert_eq!(Difference::Patch.as_str(), "patch");
    assert_eq!(Difference::PrePatch.as_str(), "prepatch");
    assert_eq!(Difference::PreRelease.as_str(), "prerelease");
}

#[test]
fn difference_is_prerelease() {
    assert!(!Difference::Major.is_prerelease());
    assert!(!Difference::Patch.is_prerelease());
    assert!(Difference::PreMajor.is_prerelease());
    assert!(Difference::PreRelease.is_prerelease());
}

// ---------------------------------------------------------------------------
// diff_str convenience
// ---------------------------------------------------------------------------

#[test]
fn diff_str_parses_and_diffs() {
    assert_eq!(diff_str("1.0.0", "1.0.1").unwrap(), Some(Difference::Patch));
    assert_eq!(diff_str("1.0.0", "1.0.0").unwrap(), None);
    assert!(diff_str("not-a-version", "1.0.0").is_err());
}