[plugin] activate and deactivate event

[rino1]

Here is the structure of my scenario

├── xxx
│   ├── composer.json
└── yyy
    ├── composer.json
    └── src
        └── Main.php

Let's examine the files

cat ./xxx/composer.json
{
    "repositories": {
        "metapackage": {
            "type": "path",
            "url": "../yyy"
        }
    },
    "config": {
        "allow-plugins": {
            "yyy/yyy": true
        }
    }
}

cat ./yyy/composer.json
{
    "name": "yyy/yyy",
    "type": "composer-plugin",
    "extra": {
        "class": "Main"
    },
    "require": {
        "composer-plugin-api": "^2.0"
    },
    "autoload": {
        "psr-4": {
            "": "src"
        }
    }
}

cat ./yyy/src/Main.php
<?php

use Composer\{
    Composer,
    IO\IOInterface,
    Plugin\PluginInterface as Plugin,
};

final class Main implements Plugin
{

    private $invoked = [
        'actibate' => false,
        'deactivate' => false,
        'uninstall' => false,
    ];

    /*
     * NOTE
     * activate, deactivate and uninstall methods,
     * call __invoke magic method
     * https://www.php.net/manual/en/language.oop5.magic.php#object.invoke
     */

    function activate(Composer $composer, IOInterface $io)
    {
        $this(__FUNCTION__);
    }

    function deactivate(Composer $composer, IOInterface $io)
    {
        $this(__FUNCTION__);
    }

    function uninstall(Composer $composer, IOInterface $io)
    {
        $this(__FUNCTION__);
    }

    function __invoke($event)
    {
        $this->invoked[$event] = true;
        $this->echoHighlight("$event event invoked");
    }

    private function echoHighlight($lines, $eol = PHP_EOL)
    {
        $lines = (array) $lines;

        foreach ($lines as $line) {
            printf(
                "[Highlight] %s%s",
                $line,
                $eol
            );
        }
    }

    function __destruct()
    {
        $deepenings = [];

        if ($this->invoked['deactivate'] && $this->invoked['uninstall']) {
            array_push(
                $deepenings,
                "Justifiable: deactivate and uninstall events both were invoked. Before uninstalling a plugin, it is generally advisable to deactivate it"
            );
        }

        if ($this->invoked['activate'] && $this->invoked['deactivate']) {
            array_push(
                $deepenings,
                "Warning: activate and deactivate events they should be contrasting. Because they were both called?"
            );
        }

        $this->echoHighlight($deepenings);
    }

}

Let's do some tests

++ cd xxx
++ composer require yyy/yyy:@dev
./composer.json has been updated
Running composer update yyy/yyy
Loading composer repositories with package information
Updating dependencies
Lock file operations: 1 install, 0 updates, 0 removals
  - Locking yyy/yyy (dev-main)
Writing lock file
Installing dependencies from lock file (including require-dev)
Package operations: 1 install, 0 updates, 0 removals
  - Installing yyy/yyy (dev-main): Symlinking from ../yyy
[Highlight] activate event invoked
Generating autoload files
++ composer update yyy/yyy:@dev
[Highlight] activate event invoked
Loading composer repositories with package information
Updating dependencies
Lock file operations: 0 installs, 0 updates, 0 removals
Installing dependencies from lock file (including require-dev)
Nothing to install, update or remove
Generating autoload files
++ composer remove yyy/yyy
[Highlight] activate event invoked
./composer.json has been updated
[Highlight] deactivate event invoked
[Highlight] Warning: activate and deactivate events they should be contrasting. Because they were both called?
[Highlight] activate event invoked
Running composer update yyy/yyy
Loading composer repositories with package information
Updating dependencies
Lock file operations: 0 installs, 0 updates, 1 removal
  - Removing yyy/yyy (dev-main)
Writing lock file
Installing dependencies from lock file (including require-dev)
Package operations: 0 installs, 0 updates, 1 removal
[Highlight] deactivate event invoked
[Highlight] uninstall event invoked
[Highlight] Justifiable: deactivate and uninstall events both were invoked. Before uninstalling a plugin, it is generally advisable to deactivate it
[Highlight] Warning: activate and deactivate events they should be contrasting. Because they were both called?
  - Removing yyy/yyy (dev-main)
Generating autoload files

Let's summarize a bit...

+++ composer require yyy/yyy:@dev
[Highlight] activate event invoked
+++ composer update yyy/yyy:@dev
[Highlight] activate event invoked
+++ composer remove yyy/yyy
[Highlight] activate event invoked
[Highlight] deactivate event invoked
[Highlight] Warning: activate and deactivate events they should be contrasting. Because they were both called?
[Highlight] activate event invoked
[Highlight] deactivate event invoked
[Highlight] uninstall event invoked
[Highlight] Justifiable: deactivate and uninstall events both were invoked. Before uninstalling a plugin, it is generally advisable to deactivate it
[Highlight] Warning: activate and deactivate events they should be contrasting. Because they were both called?

Like seeing some things are good, some are not.
Let's analyze...

+++ composer require yyy/yyy:@dev
[Highlight] activate event invoked
+++ composer update yyy/yyy:@dev
[Highlight] activate event invoked

OK!!!

+++ composer remove yyy/yyy
[Highlight] activate event invoked
[Highlight] deactivate event invoked
[Highlight] Warning: activate and deactivate events they should be contrasting. Because they both were called?

Why?

[Highlight] activate event invoked
[Highlight] deactivate event invoked
[Highlight] uninstall event invoked
[Highlight] Justifiable: deactivate and uninstall events both were invoked. Before uninstalling a plugin, it is generally advisable to deactivate it

OK!!!

[Highlight] Warning: activate and deactivate events they should be contrasting. Because they were both called?

Why?

[Seldaek]

Sorry but I have no idea what you are asking here.

[rino1]

Because when I give the command

$ composer remove yyy/yyy

all three events (activate, deactivate, uninstall) are invoked?

[Seldaek]

Yes that's as expected imo, the plug-in gets activated when composer starts as it is installed then it gets deactivated and un-installed if you remove it

[rino1]

OK.
But to deactivate a plugin?

$ composer deactivate ...
Command "deactivate" is not defined.

it does not work...

[Seldaek]

Activate and deactivate only happen at runtime when plugins are loaded and unloaded, then uninstall only happens when a plug-in is removed.

[rino1]

Activate and deactivate only happen at runtime when plugins are loaded

OK

and unloaded,

Meaning what? [1]

then uninstall only happens when a plug-in is removed.

OK

[1] In other words, what purpose does the deactivate event serve?
In what concrete situation should it be exploited?
An example?

[Seldaek]

deactivate could be used to unregister event listeners that were registered in activate for example. Because when a plugin gets upgraded it will be activated when composer boots, then deactivated, then upgraded, then activated with the new version

[rino1]

At this point, however, I wouldn't call the event disable (it's confusing), but update (or beforeUpdate).
It's more appropriate, more intuitive IHMO

[rino1]

thanks!!!