symfony
diff --git a/‎src/Symfony/Installer/NewCommand.php
Copy file name to clipboardExpand all lines: src/Symfony/Installer/NewCommand.php
+16-6Lines changed: 16 additions & 6 deletions b/‎src/Symfony/Installer/NewCommand.php
Copy file name to clipboardExpand all lines: src/Symfony/Installer/NewCommand.php
+16-6Lines changed: 16 additions & 6 deletions
diff --git a/‎tests/Symfony/Installer/Tests/IntegrationTest.php
Copy file name to clipboardExpand all lines: tests/Symfony/Installer/Tests/IntegrationTest.php
+13Lines changed: 13 additions & 0 deletions b/‎tests/Symfony/Installer/Tests/IntegrationTest.php
Copy file name to clipboardExpand all lines: tests/Symfony/Installer/Tests/IntegrationTest.php
+13Lines changed: 13 additions & 0 deletions
@@ -139,7 +139,7 @@ protected function checkSymfonyVersionIsInstallable()
                 throw new \RuntimeException(sprintf(
                     "The selected branch (%s) does not exist, or is not maintained.\n".
                     "To solve this issue, install Symfony with the latest stable release:\n\n".
-                    '%s %s %s',  $this->version, $_SERVER['PHP_SELF'], $this->getName(), $this->projectDir
+                    '%s %s %s', $this->version, $_SERVER['PHP_SELF'], $this->getName(), $this->projectDir
                 ));
             }
 
@@ -173,11 +173,21 @@ protected function checkSymfonyVersionIsInstallable()
         }
 
         // check that the system has the PHP version required by the Symfony version to be installed
-        if (version_compare($this->version, '3.0.0', '>=') && version_compare(phpversion(), '5.5.9', '<')) {
+        if (version_compare($this->version, '3.0.0', '>=') && version_compare(PHP_VERSION, '5.5.9', '<')) {
             throw new \RuntimeException(sprintf(
                 "The selected version (%s) cannot be installed because it requires\n".
                 "PHP 5.5.9 or higher and your system has PHP %s installed.\n",
-                $this->version, phpversion()
+                $this->version, PHP_VERSION
+            ));
+        }
+
+        // check that the Symfony version to be installed is not 4.x, which is incompatible with this installer
+        if (version_compare($this->version, '4.0.0', '>=')) {
+            throw new \RuntimeException(sprintf(
+                "The Symfony Installer is not compatible with Symfony 4.x or newer versions.\n".
+                "Run this other command to install Symfony using Composer instead:\n\n".
+                'composer create-project symfony/skeleton %s',
+                $this->projectName
             ));
         }
 
@@ -329,12 +339,12 @@ protected function updateParameters()
     protected function updateComposerConfig()
     {
         parent::updateComposerConfig();
-        $this->composerManager->updateProjectConfig([
+        $this->composerManager->updateProjectConfig(array(
             'name' => $this->composerManager->createPackageName($this->projectName),
             'license' => 'proprietary',
             'description' => null,
-            'extra' => ['branch-alias' => null],
-        ]);
+            'extra' => array('branch-alias' => null),
+        ));
 
         return $this;
     }
 
@@ -101,6 +101,19 @@ public function testSymfonyRequiresNewerPhpVersion()
         $this->runCommand(sprintf('php %s/symfony.phar new my_test_project 3.0.0', $this->rootDir));
     }
 
+    /**
+     * @expectedException \RuntimeException
+     * @expectedExceptionMessageRegExp /.+The Symfony Installer is not compatible with Symfony 4\.x or newer versions.*Run this other command to install Symfony using Composer instead:.*composer create-project symfony\/skeleton .+/s
+     */
+    public function testUseComposerToInstallSymfony4()
+    {
+        if (PHP_VERSION_ID < 50500) {
+            $this->markTestSkipped('This test requires PHP 5.5 or newer.');
+        }
+
+        $this->runCommand(sprintf('php %s/symfony.phar new my_test_project', $this->rootDir));
+    }
+
     public function testSymfonyInstallationInCurrentDirectory()
     {
         $projectDir = sprintf('%s/my_test_project', sys_get_temp_dir());