Fixes #67: Adds ability to disable all or certain installers

README.md

@@ -52,7 +52,7 @@ is not needed to install packages with these frameworks:
 | Decibel      | `decibel-app`
 | DokuWiki     | `dokuwiki-plugin`<br>`dokuwiki-template`
 | Dolibarr     | `dolibarr-module`
-| Drupal       | <b>`drupal-core`<br>`drupal-module`<br>`drupal-theme`</b><br>`drupal-library`<br>`drupal-profile`<br>`drupal-drush`
+| Drupal       | <b>`drupal-core`<br>`drupal-module`<br>`drupal-theme`</b><br>`drupal-library`<br>`drupal-profile`<br>`drupal-drush`<br>`drupal-custom-theme`<br>`drupal-custom-module`
 | Elgg         | `elgg-plugin`
 | Eliasis      | `eliasis-component`<br>`eliasis-module`<br>`eliasis-plugin`<br>`eliasis-template`
 | ExpressionEngine 3         | `ee3-addon`<br>`ee3-theme`
@@ -207,6 +207,51 @@ will allow this:
 Please note the name entered into `installer-name` will be the final and will
 not be inflected.
 
+## Disabling installers
+
+There may be time when you want to disable one or more installers from `composer/installers`.
+For example, if you are managing a package or project that uses a framework specific installer that
+conflicts with `composer/installers` but also have a dependency on a package that depends on `composer/installers`.
+
+Installers can be disabled for your project by specifying the extra
+`installer-disable` property. If set to `true`, `"all"`, or `"*"` all installers
+will be disabled. 
+
+```json
+{
+    "extra": {
+        "installer-disable": true
+    }
+}
+```
+
+Otherwise a single installer or an array of installers may be specified.
+
+```json
+{
+    "extra": {
+        "installer-disable": [
+            "cakephp",
+            "drupal"
+        ]
+    }
+}
+```
+
+**Note:** Using a global disable value (`true`, `"all"`, or `"*"`) will take precedence over individual
+installer names if used in an array. The example below will disable all installers.
+
+```json
+{
+    "extra": {
+        "installer-disable": [
+          "drupal",
+          "all"
+        ]
+    }
+}
+```
+
 ## Should we allow dynamic package types or paths? No.
 
 What are they? The ability for a package author to determine where a package

src/Composer/Installers/DrupalInstaller.php

@@ -11,6 +11,6 @@ class DrupalInstaller extends BaseInstaller
         'profile'   => 'profiles/{$name}/',
         'drush'     => 'drush/{$name}/',
 	    'custom-theme' => 'themes/custom/{$name}/',
-	    'custom-module' => 'modules/custom/{$name}',
+	    'custom-module' => 'modules/custom/{$name}/',
     );
 }

src/Composer/Installers/Installer.php

@@ -1,13 +1,18 @@
 <?php
+
 namespace Composer\Installers;
 
-use Composer\IO\IOInterface;
+use Composer\Composer;
+use Composer\Installer\BinaryInstaller;
 use Composer\Installer\LibraryInstaller;
+use Composer\IO\IOInterface;
 use Composer\Package\PackageInterface;
 use Composer\Repository\InstalledRepositoryInterface;
+use Composer\Util\Filesystem;
 
 class Installer extends LibraryInstaller
 {
+
     /**
      * Package types to installer class map
      *
@@ -103,6 +108,30 @@ class Installer extends LibraryInstaller
         'prestashop'   => 'PrestashopInstaller'
     );
 
+    /**
+     * Installer constructor.
+     *
+     * Disables installers specified in main composer extra installer-disable
+     * list
+     *
+     * @param IOInterface          $io
+     * @param Composer             $composer
+     * @param string               $type
+     * @param Filesystem|null      $filesystem
+     * @param BinaryInstaller|null $binaryInstaller
+     */
+    public function __construct(
+        IOInterface $io,
+        Composer $composer,
+        $type = 'library',
+        Filesystem $filesystem = null,
+        BinaryInstaller $binaryInstaller = null
+    ) {
+        parent::__construct($io, $composer, $type, $filesystem,
+            $binaryInstaller);
+        $this->removeDisabledInstallers();
+    }
+
     /**
      * {@inheritDoc}
      */
@@ -198,4 +227,48 @@ private function getIO()
     {
         return $this->io;
     }
+
+    /**
+     * Look for installers set to be disabled in composer's extra config and
+     * remove them from the list of supported installers.
+     *
+     * Globals:
+     *  - true, "all", and "*" - disable all installers.
+     *  - false - enable all installers (useful with
+     *     wikimedia/composer-merge-plugin or similar)
+     *
+     * @return void
+     */
+    protected function removeDisabledInstallers()
+    {
+        $extra = $this->composer->getPackage()->getExtra();
+
+        if (!isset($extra['installer-disable']) || $extra['installer-disable'] === false) {
+            // No installers are disabled
+            return;
+        }
+
+        // Get installers to disable
+        $disable = $extra['installer-disable'];
+
+        // Ensure $disabled is an array
+        if (!is_array($disable)) {
+            $disable = array($disable);
+        }
+
+        // Check which installers should be disabled
+        $all = array(true, "all", "*");
+        $intersect = array_intersect($all, $disable);
+        if (!empty($intersect)) {
+            // Disable all installers
+            $this->supportedTypes = array();
+        } else {
+            // Disable specified installers
+            foreach ($disable as $key => $installer) {
+                if (is_string($installer) && key_exists($installer, $this->supportedTypes)) {
+                    unset($this->supportedTypes[$installer]);
+                }
+            }
+        }
+    }
 }

tests/Composer/Installers/Test/InstallerTest.php

@@ -1,12 +1,12 @@
 <?php
 namespace Composer\Installers\Test;
 
+use Composer\Composer;
+use Composer\Config;
 use Composer\Installers\Installer;
-use Composer\Util\Filesystem;
 use Composer\Package\Package;
 use Composer\Package\RootPackage;
-use Composer\Composer;
-use Composer\Config;
+use Composer\Util\Filesystem;
 
 class InstallerTest extends TestCase
 {
@@ -52,6 +52,10 @@ public function setUp()
 
         $this->repository = $this->getMock('Composer\Repository\InstalledRepositoryInterface');
         $this->io = $this->getMock('Composer\IO\IOInterface');
+
+        $consumerPackage = new RootPackage('foo/bar', '1.0.0', '1.0.0');
+        $this->composer->setPackage($consumerPackage);
+
     }
 
     /**
@@ -116,7 +120,14 @@ public function dataForTestSupport()
             array('decibel-app', true),
             array('dokuwiki-plugin', true),
             array('dokuwiki-template', true),
+            array('drupal-core', true),
             array('drupal-module', true),
+            array('drupal-theme', true),
+            array('drupal-library', true),
+            array('drupal-profile', true),
+            array('drupal-drush', true),
+            array('drupal-custom-theme', true),
+            array('drupal-custom-module', true),
             array('dolibarr-module', true),
             array('ee3-theme', true),
             array('ee3-addon', true),
@@ -279,10 +290,14 @@ public function dataForTestInstallPath()
             array('dokuwiki-plugin', 'lib/plugins/someplugin/', 'author/someplugin'),
             array('dokuwiki-template', 'lib/tpl/sometemplate/', 'author/sometemplate'),
             array('dolibarr-module', 'htdocs/custom/my_module/', 'shama/my_module'),
+            array('drupal-core', 'core/', 'drupal/core'),
             array('drupal-module', 'modules/my_module/', 'shama/my_module'),
-            array('drupal-theme', 'themes/my_module/', 'shama/my_module'),
-            array('drupal-profile', 'profiles/my_module/', 'shama/my_module'),
-            array('drupal-drush', 'drush/my_module/', 'shama/my_module'),
+            array('drupal-theme', 'themes/my_theme/', 'shama/my_theme'),
+            array('drupal-library', 'libraries/my_library/', 'shama/my_library'),
+            array('drupal-profile', 'profiles/my_profile/', 'shama/my_profile'),
+            array('drupal-drush', 'drush/my_command/', 'shama/my_command'),
+            array('drupal-custom-theme', 'themes/custom/my_theme/', 'shama/my_theme'),
+            array('drupal-custom-module', 'modules/custom/my_module/', 'shama/my_module'),
             array('elgg-plugin', 'mod/sample_plugin/', 'test/sample_plugin'),
             array('eliasis-component', 'components/my_component/', 'shama/my_component'),
             array('eliasis-module', 'modules/my_module/', 'shama/my_module'),
@@ -433,9 +448,7 @@ public function testCustomInstallPath()
         $installer = new Installer($this->io, $this->composer);
         $package = new Package('shama/ftp', '1.0.0', '1.0.0');
         $package->setType('cakephp-plugin');
-        $consumerPackage = new RootPackage('foo/bar', '1.0.0', '1.0.0');
-        $this->composer->setPackage($consumerPackage);
-        $consumerPackage->setExtra(array(
+        $this->composer->getPackage()->setExtra(array(
             'installer-paths' => array(
                 'my/custom/path/{$name}/' => array(
                     'shama/ftp',
@@ -470,9 +483,7 @@ public function testCustomTypePath()
         $installer = new Installer($this->io, $this->composer);
         $package = new Package('slbmeh/my_plugin', '1.0.0', '1.0.0');
         $package->setType('wordpress-plugin');
-        $consumerPackage = new RootPackage('foo/bar', '1.0.0', '1.0.0');
-        $this->composer->setPackage($consumerPackage);
-        $consumerPackage->setExtra(array(
+        $this->composer->getPackage()->setExtra(array(
             'installer-paths' => array(
                 'my/custom/path/{$name}/' => array(
                     'type:wordpress-plugin'
@@ -491,9 +502,7 @@ public function testVendorPath()
         $installer = new Installer($this->io, $this->composer);
         $package = new Package('penyaskito/my_module', '1.0.0', '1.0.0');
         $package->setType('drupal-module');
-        $consumerPackage = new RootPackage('drupal/drupal', '1.0.0', '1.0.0');
-        $this->composer->setPackage($consumerPackage);
-        $consumerPackage->setExtra(array(
+        $this->composer->getPackage()->setExtra(array(
           'installer-paths' => array(
             'modules/custom/{$name}/' => array(
               'vendor:penyaskito'
@@ -549,4 +558,44 @@ public function testUninstallAndDeletePackageFromLocalRepo()
 
         $installer->uninstall($repo, $package);
     }
+
+    /**
+     * testDisabledInstallers
+     *
+     * @dataProvider dataForTestDisabledInstallers
+     */
+    public function testDisabledInstallers($disabled, $type, $expected)
+    {
+        $this->composer->getPackage()->setExtra(array(
+            'installer-disable' => $disabled,
+        ));
+        $this->testSupports($type, $expected);
+    }
+
+    /**
+     * dataForTestDisabledInstallers
+     *
+     * @return array
+     */
+    public function dataForTestDisabledInstallers()
+    {
+        return array(
+            array(false, "drupal-module", true),
+            array(true, "drupal-module", false),
+            array("true", "drupal-module", true),
+            array("all", "drupal-module", false),
+            array("*", "drupal-module", false),
+            array("cakephp", "drupal-module", true),
+            array("drupal", "cakephp-plugin", true),
+            array("cakephp", "cakephp-plugin", false),
+            array("drupal", "drupal-module", false),
+            array(array("drupal", "cakephp"), "cakephp-plugin", false),
+            array(array("drupal", "cakephp"), "drupal-module", false),
+            array(array("cakephp", true), "drupal-module", false),
+            array(array("cakephp", "all"), "drupal-module", false),
+            array(array("cakephp", "*"), "drupal-module", false),
+            array(array("cakephp", "true"), "drupal-module", true),
+            array(array("drupal", "true"), "cakephp-plugin", true),
+        );
+    }
 }