[Performance] Implement command loader to reduce initialization time of Magento CLI

app/code/Magento/Backend/Console/Command/MaintenanceAllowIpsCommand.php

@@ -22,9 +22,10 @@ class MaintenanceAllowIpsCommand extends AbstractSetupCommand
     /**
      * Names of input arguments or options
      */
-    const INPUT_KEY_IP = 'ip';
-    const INPUT_KEY_NONE = 'none';
-    const INPUT_KEY_ADD = 'add';
+    public const INPUT_KEY_IP = 'ip';
+    public const INPUT_KEY_NONE = 'none';
+    public const INPUT_KEY_ADD = 'add';
+    public const NAME = 'maintenance:allow-ips';
 
     /**
      * @var MaintenanceMode
@@ -76,7 +77,7 @@ protected function configure(): void
                 'Add the IP address to existing list'
             ),
         ];
-        $this->setName('maintenance:allow-ips')
+        $this->setName(self::NAME)
             ->setDescription('Sets maintenance mode exempt IPs')
             ->setDefinition(array_merge($arguments, $options));
 

app/code/Magento/Backend/Console/Command/MaintenanceDisableCommand.php

@@ -10,14 +10,16 @@
  */
 class MaintenanceDisableCommand extends AbstractMaintenanceCommand
 {
+    public const NAME = 'maintenance:disable';
+
     /**
      * Initialization of the command
      *
      * @return void
      */
     protected function configure()
     {
-        $this->setName('maintenance:disable')->setDescription('Disables maintenance mode');
+        $this->setName(self::NAME)->setDescription('Disables maintenance mode');
 
         parent::configure();
     }

app/code/Magento/Backend/Console/Command/MaintenanceEnableCommand.php

@@ -10,14 +10,16 @@
  */
 class MaintenanceEnableCommand extends AbstractMaintenanceCommand
 {
+    public const NAME = 'maintenance:enable';
+
     /**
      * Initialization of the command
      *
      * @return void
      */
     protected function configure(): void
     {
-        $this->setName('maintenance:enable')->setDescription('Enables maintenance mode');
+        $this->setName(self::NAME)->setDescription('Enables maintenance mode');
 
         parent::configure();
     }

app/code/Magento/Backend/Console/Command/MaintenanceStatusCommand.php

@@ -16,6 +16,8 @@
  */
 class MaintenanceStatusCommand extends AbstractSetupCommand
 {
+    public const NAME = 'maintenance:status';
+
     /**
      * @var MaintenanceMode $maintenanceMode
      */
@@ -40,7 +42,7 @@ public function __construct(MaintenanceMode $maintenanceMode)
      */
     protected function configure(): void
     {
-        $this->setName('maintenance:status')
+        $this->setName(self::NAME)
             ->setDescription('Displays maintenance mode status');
 
         parent::configure();

dev/tests/static/testsuite/Magento/Test/Integrity/Library/DependencyTest.php

@@ -39,7 +39,7 @@ protected function getAllowedNamespaces()
             'Framework',
             'SomeModule',
             'ModuleName',
-            'Setup\Console\CommandList',
+            'Setup\Console\CommandLoader',
             'Setup\Console\CompilerPreparation',
             'Setup\Model\ObjectManagerProvider',
             'Setup\Mvc\Bootstrap\InitParamListener',

lib/internal/Magento/Framework/App/Test/Unit/Console/CommandLoader/AggregateTest.php

@@ -0,0 +1,120 @@
+<?php
+declare(strict_types=1);
+/**
+ * Copyright © Magento, Inc. All rights reserved.
+ * See COPYING.txt for license details.
+ */
+namespace Magento\Framework\App\Test\Unit\Console\CommandLoader;
+
+use Magento\Framework\Console\CommandLoader\Aggregate;
+use PHPUnit\Framework\MockObject\MockObject;
+use PHPUnit\Framework\TestCase;
+use Symfony\Component\Console\Command\Command;
+use Symfony\Component\Console\CommandLoader\CommandLoaderInterface;
+use Symfony\Component\Console\Exception\CommandNotFoundException;
+
+/**
+ * Tests the "aggregate" command loader
+ * @see Aggregate
+ */
+class AggregateTest extends TestCase
+{
+    /** @var CommandLoaderInterface|MockObject */
+    private MockObject|CommandLoaderInterface $firstMockCommandLoader;
+
+    /** @var CommandLoaderInterface|MockObject */
+    private MockObject|CommandLoaderInterface $secondMockCommandLoader;
+
+    /** @var Aggregate */
+    private Aggregate $aggregateCommandLoader;
+
+    protected function setUp(): void
+    {
+        $this->firstMockCommandLoader = $this->getMockBuilder(CommandLoaderInterface::class)->getMock();
+        $this->secondMockCommandLoader = $this->getMockBuilder(CommandLoaderInterface::class)->getMock();
+        $this->aggregateCommandLoader = new Aggregate([$this->firstMockCommandLoader, $this->secondMockCommandLoader]);
+    }
+
+    /**
+     * Test the various cases of `has` for the aggregate command loader:
+     *  - When at least one "internal" command loader has a command, the aggregate does as well
+     *  - When none of the "internal" command loaders has a command, neither does the aggregate
+     *
+     * @dataProvider provideTestCasesForHas
+     */
+    public function testHas(bool $firstResult, bool $secondResult, bool $overallResult): void
+    {
+        $this->firstMockCommandLoader->method('has')->with('foo')->willReturn($firstResult);
+        $this->secondMockCommandLoader->method('has')->with('foo')->willReturn($secondResult);
+
+        $this->assertEquals($overallResult, $this->aggregateCommandLoader->has('foo'));
+    }
+
+    public function provideTestCasesForHas(): array
+    {
+        return [
+            [true, false, true],
+            [false, true, true],
+            [false, false, false]
+        ];
+    }
+
+    /**
+     * Test the various cases of `get` for the aggregate command loader. Similar to `has`,
+     * the return value of `Aggregate::get` mirrors its internal command loaders.
+     *
+     * For simplicity, this test does not cover the "no results" case. @see testGetThrow
+     *
+     * @dataProvider provideTestCasesForGet
+     */
+    public function testGet(?Command $firstCmd, ?Command $secondCmd): void
+    {
+        $firstHas = (bool)$firstCmd;
+        $secondHas = (bool)$secondCmd;
+        $this->firstMockCommandLoader->method('has')->with('foo')->willReturn($firstHas);
+        $this->firstMockCommandLoader->method('get')->with('foo')->willReturn($firstCmd);
+        $this->secondMockCommandLoader->method('has')->with('foo')->willReturn($secondHas);
+        $this->secondMockCommandLoader->method('get')->with('foo')->willReturn($secondCmd);
+
+        $this->assertInstanceOf(Command::class, $this->aggregateCommandLoader->get('foo'));
+    }
+
+    public function provideTestCasesForGet(): array
+    {
+        return [
+            [
+                new Command(),
+                null
+            ],
+            [
+                null,
+                new Command()
+            ]
+        ];
+    }
+
+    /**
+     * When none of the internal command loaders have matching commands, the aggregate command loader
+     * will throw an exception. @see CommandNotFoundException
+     */
+    public function testGetThrow(): void
+    {
+        $this->firstMockCommandLoader->method('has')->with('foo')->willReturn(false);
+        $this->secondMockCommandLoader->method('has')->with('foo')->willReturn(false);
+
+        $this->expectException(CommandNotFoundException::class);
+        $this->aggregateCommandLoader->get('foo');
+    }
+
+    /**
+     * An aggregate command loader's `getNames` method returns the merged array of the `getNames`
+     * return values of all its internal command loaders
+     */
+    public function testGetNames(): void
+    {
+        $this->firstMockCommandLoader->method('getNames')->willReturn(['foo', 'bar']);
+        $this->secondMockCommandLoader->method('getNames')->willReturn(['baz', 'qux']);
+
+        $this->assertEquals(['foo', 'bar', 'baz', 'qux'], $this->aggregateCommandLoader->getNames());
+    }
+}

lib/internal/Magento/Framework/App/Test/Unit/Console/CommandLoaderTest.php

@@ -0,0 +1,116 @@
+<?php
+declare(strict_types=1);
+/**
+ * Copyright © Magento, Inc. All rights reserved.
+ * See COPYING.txt for license details.
+ */
+namespace Magento\Framework\App\Test\Unit\Console;
+
+use Magento\Framework\Console\CommandLoader;
+use Magento\Framework\ObjectManagerInterface;
+use PHPUnit\Framework\MockObject\MockObject;
+use PHPUnit\Framework\TestCase;
+use Symfony\Component\Console\Command\Command;
+use Symfony\Component\Console\Exception\CommandNotFoundException;
+
+class CommandLoaderTest extends TestCase
+{
+    /** @var MockObject|ObjectManagerInterface */
+    private ObjectManagerInterface|MockObject $objectManagerMock;
+
+    protected function setUp(): void
+    {
+        $this->objectManagerMock = $this->getMockBuilder(ObjectManagerInterface::class)->getMock();
+    }
+
+    /**
+     * Test that the command loader, when provided zero commands, does not have a command named "foo"
+     */
+    public function testHasWithZeroCommands(): void
+    {
+        $subj = new CommandLoader($this->objectManagerMock, []);
+
+        $this->assertFalse($subj->has('foo'));
+    }
+
+    /**
+     * Test that the command loader will return true when provided with a command "foo"
+     */
+    public function testHasWithAtLeastOneCommand(): void
+    {
+        $subj = new CommandLoader($this->objectManagerMock, [
+            [
+                'name' => 'foo',
+                'class' => FooCommand::class
+            ]
+        ]);
+
+        $this->assertTrue($subj->has('foo'));
+    }
+
+    /**
+     * Test that the command loader will throw a CommandNotFoundException when it does not have the requested command
+     */
+    public function testGetWithZeroCommands(): void
+    {
+        $subj = new CommandLoader($this->objectManagerMock, []);
+
+        $this->expectException(CommandNotFoundException::class);
+
+        $subj->get('foo');
+    }
+
+    /**
+     * Test that the command loader returns a command when one it has is requested
+     */
+    public function testGetWithAtLeastOneCommand(): void
+    {
+        $this->objectManagerMock
+            ->method('create')
+            ->with(FooCommand::class)
+            ->willReturn(new FooCommand());
+
+        $subj = new CommandLoader($this->objectManagerMock, [
+            [
+                'name' => 'foo',
+                'class' => FooCommand::class
+            ]
+        ]);
+
+        $this->assertInstanceOf(FooCommand::class, $subj->get('foo'));
+    }
+
+    /**
+     * Test that the command loader will return an empty "names" array when it has none
+     */
+    public function testGetNamesWithZeroCommands(): void
+    {
+        $subj = new CommandLoader($this->objectManagerMock, []);
+
+        $this->assertEquals([], $subj->getNames());
+    }
+
+    /**
+     * Test that the command loader returns an array of its command names when `getNames` is called
+     */
+    public function testGetNames(): void
+    {
+        $subj = new CommandLoader($this->objectManagerMock, [
+            [
+                'name' => 'foo',
+                'class' => FooCommand::class
+            ],
+            [
+                'name' => 'bar',
+                'class' => 'BarCommand'
+            ]
+        ]);
+
+        $this->assertEquals(['foo', 'bar'], $subj->getNames());
+    }
+}
+
+// phpcs:ignore PSR1.Classes.ClassDeclaration
+class FooCommand extends Command
+{
+}