Finalize code review changes

.travis.yml

@@ -27,13 +27,13 @@ jobs:
         - TEST_COVERAGE=true
 
 before_install:
-  - if [[ ! -z $PHP_UNIT_VERSION ]] ; then composer require --dev --no-update phpunit/phpunit $PHP_UNIT_VERSION ; fi
-  - if [[ ! -z $COMPOSER2 ]] ; then composer self-update --snapshot ; composer config minimum-stability dev ; fi
+  - if [[ -n $PHP_UNIT_VERSION ]] ; then composer require --dev --no-update phpunit/phpunit $PHP_UNIT_VERSION ; fi
+  - if [[ -n $COMPOSER2 ]] ; then composer self-update --snapshot ; composer config minimum-stability dev ; fi
 
 install:
   - travis_retry composer install $COMPOSER_ARGS
   - if [[ $TEST_COVERAGE == 'true' ]] ; then travis_retry composer require --dev $COMPOSER_ARGS $COVERAGE_DEPS ; fi
-  - if [[ ! -z $COMPOSER2 ]] ; then travis_retry composer require --dev --with-all-dependencies $COMPOSER_ARGS composer/composer 2.0.0-alpha1 ; fi
+  - if [[ -n $COMPOSER2 ]] ; then travis_retry composer require --dev --with-all-dependencies $COMPOSER_ARGS composer/composer 2.0.0-alpha1 ; fi
 
 script:
   - if [[ $TEST_COVERAGE == 'true' ]] ; then composer test-coverage ; else composer test ; fi

test/PrivateComposerInstaller/RemoteFilesystemTest.php

@@ -13,35 +13,24 @@ class RemoteFilesystemTest extends TestCase
 
     protected function setUp(): void
     {
+        // As of Composer 2 this class is no longer in use
+        if (version_compare(PluginInterface::PLUGIN_API_VERSION, '2.0.0', '>=')) {
+            $this->markTestSkipped();
+        }
+
         $this->io = $this->createMock(IOInterface::class);
     }
 
     public function testExtendsComposerRemoteFilesystem()
     {
-        if (PluginInterface::PLUGIN_API_VERSION === '2.0.0') {
-            $this->markTestSkipped();
-        }
-
         $this->assertInstanceOf(
             \Composer\Util\RemoteFilesystem::class,
             new RemoteFilesystem('', $this->io)
         );
     }
 
-    protected function setUp(): void
-    {
-        if (version_compare(PluginInterface::PLUGIN_API_VERSION, '2.0.0', '>=')) {
-            $this->markTestSkipped();
-        }
-
-        $this->io = $this->createMock(IOInterface::class);
-    }
     public function testCopyUsesPrivateFileUrl()
     {
-        if (PluginInterface::PLUGIN_API_VERSION === '2.0.0') {
-            $this->markTestSkipped();
-        }
-
         // Test inspired by testCopy in
         // Composer\Test\Util\RemoteFilesystemTest
         $privateFileUrl = 'file://' . __FILE__;