4.x → 4.2 update instructions in preparation of the Bolt 5 upgrade

[I-Valchev]

Updating from 4.0.x or 4.1.x to 4.2 will work without issues, since Bolt follows semantic versioning. However, Bolt 4.2 also allows you to make the preparatory steps for upgrading to Bolt 5.0.

Here is how to update to Bolt 4.2 with these steps in preparation of the major release:

1. Run composer update as usual.
2. After it has completed without errors, verify that you are running version 4.2 by checking the output of php bin/console bolt:info or in Bolt's Dashboard.
3. Switch the site to development mode, if not already, by setting APP_ENV=dev and APP_DEBUG=1 in the .env file in the root of your project.
4. Locate the composer.json file in the root of your project, and make the following adjustments:

5.a Update the "scripts" section to be (if you have defined your own custom scripts, you can keep them):

"scripts": {
        "pre-install-cmd": [
            "Bolt\\ComposerScripts\\ProjectEventHandler::preInstall"
        ],
        "post-install-cmd": [
            "Bolt\\ComposerScripts\\ProjectEventHandler::postInstall"
        ],
        "pre-update-cmd": [
            "Bolt\\ComposerScripts\\ProjectEventHandler::preUpdate"
        ],
        "post-update-cmd": [
            "Bolt\\ComposerScripts\\ProjectEventHandler::postUpdate"
        ],
        "post-create-project-cmd": [
            "Bolt\\ComposerScripts\\ProjectEventHandler::postCreateProject"
        ],
        "pre-package-uninstall": [
            "Bolt\\ComposerScripts\\ProjectEventHandler::prePackageUninstall"
        ],
        "lint": "@php vendor/bin/ecs check --no-progress-bar --no-interaction",
        "lint:fix": "@php vendor/bin/ecs check --no-progress-bar --no-interaction --fix",
        "phpstan": "@php vendor/bin/phpstan --memory-limit=1G analyse -c phpstan.neon src"
    },

5.b Add a new "autoload-dev" section in the composer.json file right after the above scripts section, like so:

"autoload-dev": {
        "psr-4": {
            "App\\Tests\\": "tests/",
            "Bolt\\ComposerScripts\\": "vendor/bolt/core/bin/composer-script/"
        }
    },

6. Now run composer update. It should work without errors.