compare

Compares two version strings by semver precedence.

Both are read leniently (see Version::parse_lenient: a v prefix and missing minor or patch are fine), and build metadata is ignored.

Import

use helpers4::version::compare;

Cargo feature version (enabled by default). To compile only this module:

cargo add helpers4 --no-default-features --features version

or in Cargo.toml:

[dependencies]
helpers4 = { version = "0.0.6", default-features = false, features = ["version"] }

Signature

pub fn compare(a: &str, b: &str) -> Result<Ordering, ParseVersionError>

Parameters

Parameter	Type	Description
a	&str	The first version.
b	&str	The second version.

Returns

Result<Ordering, ParseVersionError> — Ok on success, otherwise an Err: see Errors.

Errors

The ParseVersionError of whichever string does not parse (the first one if both fail).

Examples

use helpers4::version::compare;
use std::cmp::Ordering;

assert_eq!(compare("1.10.0", "1.9.0")?, Ordering::Greater);
assert_eq!(compare("v2", "2.0.0")?, Ordering::Equal);
assert_eq!(compare("1.0.0-rc.1", "1.0.0")?, Ordering::Less);

Error type: ParseVersionError

Why a version or a version requirement could not be parsed.

use helpers4::version::ParseVersionError;

#[non_exhaustive]
pub enum ParseVersionError {
    /// The text is empty or only whitespace.
    Empty,
    /// A part is missing: `"1.2"` has no patch.
    MissingComponent {
        /// `"minor"` or `"patch"`.
        component: &'static str,
    },
    /// A part is not a number (or does not fit a `u64`).
    InvalidNumber {
        /// `"major"`, `"minor"` or `"patch"`.
        component: &'static str,
    },
    /// A number has a leading zero (`"01"`), which semver forbids.
    LeadingZero {
        /// `"major"`, `"minor"`, `"patch"` or `"prerelease"` (a numeric identifier).
        component: &'static str,
    },
    /// A pre-release or build identifier is empty or has a character outside `[0-9A-Za-z-]`.
    InvalidIdentifier,
    /// A requirement comparator is malformed: unknown operator, a wildcard where it is not
    /// allowed, a pre-release on a partial version, or build metadata.
    InvalidComparator,
}

Source

src/version/compare.rs