libversion

Advanced version string comparison library.

Need to compare software, package or whatever versions? Comparing 1.0 and 1.1 could be easy, but are you ready for more complex cases like 1.2-x.3~alpha4? libversion is, which is proven by using the library in Repology project which relies on comparing software version strings, even if they are written in different formats.

Features

A short list of version features libversion handles for you:

• Simple versions, obviously: 0.9 < 1.0 < 1.1
• Omitting insignificant components: 1.0 == 1.0.0
• Leading zeroes: 1.001 == 1.1
• Unusual separators: 1_2~3 == 1.2.3
• Letter suffixes: 1.2 < 1.2a < 1.2b < 1.3
• Alphanumeric prerelease components:
  • 1.0alpha1 == 1.0.alpha1 == 1.0a1 == 1.0.a1
  • 1.0alpha1 < 1.0alpha2 < 1.0beta1 < 1.0rc1 < 1.0
• Awareness of prerelease keywords: while 1.0 < 1.0a-1 (a treated as version addendum), but 1.0alpha-1 < 1.0 (alpha is treated as prerelease marker)
• Awareness of patch, post and pl keywords: while 1.0alpha1 < 1.0 (alpha is pre-release), but 1.0 < 1.0patch1 < 1.1 (patch is post-release)
• Customizable handling of p keyword (it may mean either patch or pre, and since libversion cannot guess, this is controlled with an external flag)

See ALGORITHM.md for more elaborate description of inner logic.

API

Version comparison

fn version_compare2(v1: &str, v2: &str);
fn version_compare4(v1: &str, v2: &str, v1_flags: Flags, int v2_flags: Flags);

Compares version strings v1 and v2.

Returns -1 if v1 is lower than v2, 0 if v1 is equal to v2 and 1 if v1 is higher than v2.

Thread safe, does not produce errors, does not allocate dynamic memory (this needs to checked for rust implementation), O(N) computational complexity, O(1) stack memory requirements.

4-argument form allows specifying flags for each version argument to tune comparison behavior in specific cases. Currently supported flags values are:

• Flags:PIsPatch p letter is treated as patch (post-release) instead of pre (pre-release).
• Flags::AnyIsPatch any letter sequence is treated as post-release (useful for handling patchsets as in 1.2foopatchset3.barpatchset4).
• Flags::LowerBound derive lowest possible version with the given prefix. For example, lower bound for 1.0 is such imaginary version ? that it's higher than any release before 1.0 and lower than any prerelease of 1.0. E.g. 0.999 < lower bound(1.0) < 1.0alpha0.
• Flags::UpperBound derive highest possible version with the given prefix. Opposite of Flags::LowerBound.

If both flags are zero, version_compare4 acts exactly the same as version_compare2.

Example

(TODO: check that this compiles after publishing the crate)

use libversion::{Flags, version_compare2, version_compare4};

int main() {
    // 0.99 < 1.11
    assert_eq!(version_compare2("0.99", "1.11"), -1);

    // 1.0 == 1.0.0
    assert_eq!(version_compare2("1.0", "1.0.0"), 0);

    // 1.0alpha1 < 1.0.rc1
    assert_eq!(version_compare2("1.0alpha1", "1.0.rc1"), -1);

    // 1.0 > 1.0.rc1
    assert_eq!(version_compare2("1.0", "1.0-rc1"), 1);

    // 1.2.3alpha4 is the same as 1.2.3~a4
    assert_eq!(version_compare2("1.2.3alpha4", "1.2.3~a4"), 0);

    // by default, `p' is treated as `pre'...
    assert_eq!(version_compare2("1.0p1", "1.0pre1"), 0);
    assert_eq!(version_compare2("1.0p1", "1.0post1"), -1);
    assert_eq!(version_compare2("1.0p1", "1.0patch1"), -1);

    // ...but this is tunable: here it's handled as `patch`
    assert_eq!(version_compare4("1.0p1", "1.0pre1", Flags::PIsPatch, Flags::empty()), 1);
    assert_eq!(version_compare4("1.0p1", "1.0post1", Flags::PIsPatch, Flags::empty()), 0);
    assert_eq!(version_compare4("1.0p1", "1.0patch1", Flags::PIsPatch, Flags::empty()), 0);

    // a way to check that the version belongs to a given release
    assert_eq!(version_compare4("1.0alpha1", "1.0", Flags::empty(), Flags::LowerBound), 1);
	assert_eq!(version_compare4("1.0alpha1", "1.0", Flags::empty(), Flags::UpperBound), -1);

    assert_eq!(version_compare4("1.0.1", "1.0", Flags::empty(), Flags::LowerBound), 1);
    assert_eq!(version_compare4("1.0.1", "1.0", Flags::empty(), Flags::UpperBound), -1);
    // 1.0alpha1 and 1.0.1 belong to 1.0 release, e.g. they lie between
    // (lowest possible version in 1.0) and (highest possible version in 1.0)
}

Bindings and compatible implementations

• Python: py-libversion by @AMDmi3
• Go: golibversion by @saenai255
• Rust: libversion-rs by @AMDmi3

Author

• Dmitry Marakasov amdmi3@amdmi3.ru

License

• MIT