From dd0d97e643d722c0a4d7df42116ec0076a47d6fc Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Gr=C3=A9goire=20Pineau?= <lyrixx@lyrixx.info>
Date: Sat, 11 Feb 2012 02:58:39 +0100
Subject: [PATCH] [Console] Added suggest on bad command name

---
 src/Symfony/Component/Console/Application.php | 32 ++++++++++++++-
 .../Component/Console/ApplicationTest.php     | 41 ++++++++++++++++++-
 2 files changed, 71 insertions(+), 2 deletions(-)

diff --git a/src/Symfony/Component/Console/Application.php b/src/Symfony/Component/Console/Application.php
index 219111737e..ce6e2ce8db 100644
--- a/src/Symfony/Component/Console/Application.php
+++ b/src/Symfony/Component/Console/Application.php
@@ -557,7 +557,14 @@ class Application
 
         $abbrevs = static::getAbbreviations(array_unique($aliases));
         if (!isset($abbrevs[$searchName])) {
-            throw new \InvalidArgumentException(sprintf('Command "%s" is not defined.', $name));
+            $message = sprintf('Command "%s" is not defined.', $name);
+
+            if ($alternatives = $this->findAlternativeCommands($searchName)) {
+                $message .= PHP_EOL.'Did you mean one of these?'.PHP_EOL.'    ';
+                $message .= implode(PHP_EOL.'    ', $alternatives);
+            }
+
+            throw new \InvalidArgumentException($message);
         }
 
         if (count($abbrevs[$searchName]) > 1) {
@@ -915,4 +922,27 @@ class Application
 
         return implode(':', null === $limit ? $parts : array_slice($parts, 0, $limit));
     }
+
+    /**
+     * Finds alternative commands of $name
+     *
+     * @param string $name The full name of the command
+     * @return array A sorted array of similar commands
+     */
+    private function findAlternativeCommands($name)
+    {
+        $alternatives = array();
+
+        foreach ($this->commands as $command) {
+            $commandName = $command->getName();
+            $lev = levenshtein($name, $commandName);
+            if ($lev <= strlen($name) / 3 || false !== strpos($commandName, $name)) {
+                $alternatives[$commandName] = $lev;
+            }
+        }
+
+        asort($alternatives);
+
+        return array_keys($alternatives);
+    }
 }
diff --git a/tests/Symfony/Tests/Component/Console/ApplicationTest.php b/tests/Symfony/Tests/Component/Console/ApplicationTest.php
index b24add6502..5a8186f57c 100644
--- a/tests/Symfony/Tests/Component/Console/ApplicationTest.php
+++ b/tests/Symfony/Tests/Component/Console/ApplicationTest.php
@@ -183,7 +183,7 @@ class ApplicationTest extends \PHPUnit_Framework_TestCase
             $this->fail('->find() throws an \InvalidArgumentException if the abbreviation is ambiguous for a namespace');
         } catch (\Exception $e) {
             $this->assertInstanceOf('\InvalidArgumentException', $e, '->find() throws an \InvalidArgumentException if the abbreviation is ambiguous for a namespace');
-            $this->assertEquals('Command "f" is not defined.', $e->getMessage(), '->find() throws an \InvalidArgumentException if the abbreviation is ambiguous for a namespace');
+            $this->assertRegExp('/Command "f" is not defined./', $e->getMessage(), '->find() throws an \InvalidArgumentException if the abbreviation is ambiguous for a namespace');
         }
 
         try {
@@ -203,6 +203,45 @@ class ApplicationTest extends \PHPUnit_Framework_TestCase
         }
     }
 
+    public function testFindAlternativeCommands()
+    {
+        $application = new Application();
+
+        $application->add(new \FooCommand());
+        $application->add(new \Foo1Command());
+        $application->add(new \Foo2Command());
+
+        try {
+            $application->find($commandName = 'Unknow command');
+            $this->fail('->find() throws an \InvalidArgumentException if command does not exist');
+        } catch (\Exception $e) {
+            $this->assertInstanceOf('\InvalidArgumentException', $e, '->find() throws an \InvalidArgumentException if command does not exist');
+            $this->assertEquals(sprintf('Command "%s" is not defined.', $commandName), $e->getMessage(), '->find() throws an \InvalidArgumentException if command does not exist, without alternatives');
+        }
+
+        try {
+            $application->find($commandName = 'foo');
+            $this->fail('->find() throws an \InvalidArgumentException if command does not exist');
+        } catch (\Exception $e) {
+            $this->assertInstanceOf('\InvalidArgumentException', $e, '->find() throws an \InvalidArgumentException if command does not exist');
+            $this->assertRegExp(sprintf('/Command "%s" is not defined./', $commandName), $e->getMessage(), '->find() throws an \InvalidArgumentException if command does not exist, with alternatives');
+            $this->assertRegExp('/foo:bar/', $e->getMessage(), '->find() throws an \InvalidArgumentException if command does not exist, with alternative : "foo:bar"');
+            $this->assertRegExp('/foo1:bar/', $e->getMessage(), '->find() throws an \InvalidArgumentException if command does not exist, with alternative : "foo1:bar"');
+            $this->assertRegExp('/foo:bar1/', $e->getMessage(), '->find() throws an \InvalidArgumentException if command does not exist, with alternative : "foo:bar1"');
+        }
+
+        // Test if "foo1" command throw an "\InvalidArgumentException" and does not contain
+        // "foo:bar" as alternative because "foo1" is too far from "foo:bar"
+        try {
+            $application->find($commandName = 'foo1');
+            $this->fail('->find() throws an \InvalidArgumentException if command does not exist');
+        } catch (\Exception $e) {
+            $this->assertInstanceOf('\InvalidArgumentException', $e, '->find() throws an \InvalidArgumentException if command does not exist');
+            $this->assertRegExp(sprintf('/Command "%s" is not defined./', $commandName), $e->getMessage(), '->find() throws an \InvalidArgumentException if command does not exist, with alternatives');
+            $this->assertFalse(strpos($e->getMessage(), 'foo:bar'), '->find() throws an \InvalidArgumentException if command does not exist, without "foo:bar" alternative');
+        }
+    }
+
     public function testSetCatchExceptions()
     {
         $application = new Application();