A VERY quick and rough tool to check your project for SilverStripe upgradability

ss4-upgradability-check.php

<?php
/**
 * Test (roughly) your SilverStripe 4 upgradability. Ensure you run "composer require composer/semver" first.
 *
 * @author Robbie Averill <robbie@silverstripe.com>
 */
require_once __DIR__ . '/vendor/autoload.php';

use Composer\Semver\Semver;

$composerConfig = @file_get_contents(__DIR__ . '/composer.json');
if ($composerConfig === false || !json_decode($composerConfig)) {
    echo 'composer.json not found or invalid. Please run this from your project root.', PHP_EOL;
    exit(1);
}
$composerConfig = json_decode($composerConfig);

echo 'Checking your dependencies for SilverStripe 4 compatibility...', PHP_EOL;

$results = [
    'pass' => 0,
    'fail' => 0,
    'skipped' => 0
];

foreach ($composerConfig->require as $package => $constraint) {
    echo ' * Testing ' . $package . '... ';

    if (in_array($package, ['silverstripe/framework', 'silverstripe/cms'])) {
        $results['pass']++;
        echo 'Pass.', PHP_EOL;
        continue;
    }

    $result = @file_get_contents('https://packagist.org/p/' . $package . '.json');
    if ($result === false || !json_decode($result)) {
        $results['skipped']++;
        echo 'Skipped - not found.', PHP_EOL;
        continue;
    }
    $result = json_decode($result);

    if (empty($result->packages->$package->{'dev-master'})) {
        $results['skipped']++;
        echo 'Skipped - master branch not found.', PHP_EOL;
        continue;
    }

    $valid = false;
    $master = $result->packages->$package->{'dev-master'};
    foreach ($master->require as $required => $version) {
        if (!in_array($required, ['silverstripe/framework', 'silverstripe/cms'])) {
            continue;
        }

        if (Semver::satisfies('4.0.0', $version)) {
            $results['pass']++;
            echo 'Pass.', PHP_EOL;
            continue 2;
        }

        $results['fail']++;
        echo 'Fail.', PHP_EOL;
        continue;
    }
}

echo PHP_EOL;
echo <<<RESULTS

Results:
---
Compatible:     {$results['pass']}
Non-compatible: {$results['fail']}
Skipped:        {$results['skipped']}

RESULTS;