The semantic version parser

SemanticVersion.php

<?php
declare(strict_types=1);

class SemanticVersion implements JsonSerializable
{
    /**
     * Regex pattern for semantic versioning
     * eg:
     * 1.2.3
     * v1.2.3
     * 1.2.3-beta
     * 1.2.3-beta.1
     * 1.2.3-beta.1+build.1
     * 1.2.3+build.1
     * 1.2.3+build.1.2
     *
     * contains array matched keys:
     * {
     *      "prefix"?: "[a-zA-Z]+",
     *      "major": "[0-9]+",
     *      "minor": "[0-9]+",
     *      "patch": "[0-9]+",
     *      "release_separator"?: "[+\-]",   // optional
     *      "release"?: "[a-zA-Z0-9]+([a-zA-Z0-9.+\-]*[a-zA-Z0-9])?",   // optional the release version
     * }
     */
    public const SEMANTIC_VERSION_REGEX = '^
(?x)
    (?<prefix>[a-zA-Z]+)? # optional prefix: eg : "v" in "v1.2.3"
    (?P<major>[0-9]+)     # major version
    \.(?P<minor>[0-9]+)   # minor version
    \.(?P<patch>[0-9]+)   # patch version
    (?:
        (?P<release_separator>[+\-])
        (?P<release>
            [a-zA-Z0-9]+            # should start with a number or a letter
            (?:
                [a-zA-Z0-9.+\-]*    # allow any number of letters, numbers, dots, plus and minus
                [a-zA-Z0-9]         # should end with a number or a letter
            )?
        ) # release version
    )?
$';

    /**
     * The version string
     *
     * @var string
     */
    public readonly string $version;

    /**
     * Is the version string valid
     *
     * @var bool
     */
    public readonly bool $valid;

    /**
     * The major version
     *
     * @var int|null
     */
    public readonly ?int $major;

    /**
     * The minor version
     *
     * @var int|null
     */
    public readonly ?int $minor;

    /**
     * The patch version
     *
     * @var int|null
     */
    public readonly ?int $patch;

    /**
     * The release separator
     *
     * @var string|null
     */
    public readonly ?string $releaseSeparator;

    /**
     * The release version
     *
     * @var string|null
     */
    public readonly ?string $release;

    /**
     * SemanticVersion constructor.
     *
     * @param string $version
     */
    public function __construct(string $version)
    {
        $this->version = trim($version);

        preg_match('/' . self::SEMANTIC_VERSION_REGEX . '/', $this->version, $matches);

        $this->valid = !empty($matches);
        $this->major = is_array($matches) && isset($matches['major']) ? (int) $matches['major'] : null;
        $this->minor = is_array($matches) && isset($matches['minor']) ? (int) $matches['minor'] : null;
        $this->patch = is_array($matches) && isset($matches['patch']) ? (int) $matches['patch'] : null;
        $this->releaseSeparator = is_array($matches)
            && isset($matches['release_separator'])
            ? $matches['release_separator']
            : null;
        $this->release = is_array($matches) && isset($matches['release']) ? $matches['release'] : null;
    }

    public function __toString(): string
    {
        return $this->version;
    }

    /**
     * @return array{
     *     version: string,
     *     valid: bool,
     *     major: int|null,
     *     minor: int|null,
     *     patch: int|null,
     *     release_separator: string|null,
     *     release: string|null
     * }
     */
    public function toArray(): array
    {
        return [
            'version' => $this->version,
            'valid' => $this->valid,
            'major' => $this->major,
            'minor' => $this->minor,
            'patch' => $this->patch,
            'release_separator' => $this->releaseSeparator,
            'release' => $this->release,
        ];
    }

    /**
     * @return array{
     *     version: string,
     *     valid: bool,
     *     major: int|null,
     *     minor: int|null,
     *     patch: int|null,
     *     release_separator: string|null,
     *     release: string|null
     * }
     */
    public function jsonSerialize(): array
    {
        return $this->toArray();
    }
}