Fix git checkouts of custom branches, fixes #889

src/Composer/Downloader/GitDownloader.php

@@ -67,7 +67,16 @@ class GitDownloader extends VcsDownloader
     {
         $template = 'git checkout %s && git reset --hard %1$s';
 
-        $command = sprintf($template, escapeshellarg($reference));
+        // check whether non-commitish are branches or tags, and fetch branches with the remote name
+        $gitRef = $reference;
+        if (!preg_match('{^[a-f0-9]{40}$}', $reference)
+            && 0 === $this->process->execute('git branch -r', $output, $path)
+            && preg_match('{^\s+composer/'.preg_quote($reference).'$}m', $output)
+        ) {
+            $gitRef = 'composer/'.$reference;
+        }
+
+        $command = sprintf($template, escapeshellarg($gitRef));
         if (0 === $this->process->execute($command, $output, $path)) {
             return;
         }
@@ -104,7 +113,7 @@ class GitDownloader extends VcsDownloader
             }
 
             // checkout the new recovered ref
-            $command = sprintf($template, escapeshellarg($newReference));
+            $command = sprintf($template, escapeshellarg($reference));
             if (0 === $this->process->execute($command, $output, $path)) {
                 $this->io->write('    '.$reference.' is gone (history was rewritten?), recovered by checking out '.$newReference);
 

tests/Composer/Test/Downloader/GitDownloaderTest.php

@@ -44,10 +44,13 @@ class GitDownloaderTest extends \PHPUnit_Framework_TestCase
         $packageMock = $this->getMock('Composer\Package\PackageInterface');
         $packageMock->expects($this->any())
             ->method('getSourceReference')
-            ->will($this->returnValue('ref'));
+            ->will($this->returnValue('1234567890123456789012345678901234567890'));
         $packageMock->expects($this->any())
             ->method('getSourceUrl')
             ->will($this->returnValue('https://example.com/composer/composer'));
+        $packageMock->expects($this->any())
+            ->method('getPrettyVersion')
+            ->will($this->returnValue('dev-master'));
         $processExecutor = $this->getMock('Composer\Util\ProcessExecutor');
 
         $expectedGitCommand = $this->getCmd("git clone 'https://example.com/composer/composer' 'composerPath' && cd 'composerPath' && git remote add composer 'https://example.com/composer/composer' && git fetch composer");
@@ -58,7 +61,7 @@ class GitDownloaderTest extends \PHPUnit_Framework_TestCase
 
         $processExecutor->expects($this->at(1))
             ->method('execute')
-            ->with($this->equalTo($this->getCmd("git checkout 'ref' && git reset --hard 'ref'")), $this->equalTo(null), $this->equalTo('composerPath'))
+            ->with($this->equalTo($this->getCmd("git checkout '1234567890123456789012345678901234567890' && git reset --hard '1234567890123456789012345678901234567890'")), $this->equalTo(null), $this->equalTo('composerPath'))
             ->will($this->returnValue(0));
 
         $downloader = $this->getDownloaderMock(null, $processExecutor);
@@ -74,6 +77,9 @@ class GitDownloaderTest extends \PHPUnit_Framework_TestCase
         $packageMock->expects($this->any())
             ->method('getSourceUrl')
             ->will($this->returnValue('https://github.com/composer/composer'));
+        $packageMock->expects($this->any())
+            ->method('getPrettyVersion')
+            ->will($this->returnValue('1.0.0'));
         $processExecutor = $this->getMock('Composer\Util\ProcessExecutor');
 
         $expectedGitCommand = $this->getCmd("git clone 'git://github.com/composer/composer' 'composerPath' && cd 'composerPath' && git remote add composer 'git://github.com/composer/composer' && git fetch composer");
@@ -101,6 +107,11 @@ class GitDownloaderTest extends \PHPUnit_Framework_TestCase
             ->will($this->returnValue(0));
 
         $processExecutor->expects($this->at(6))
+            ->method('execute')
+            ->with($this->equalTo('git branch -r'))
+            ->will($this->returnValue(0));
+
+        $processExecutor->expects($this->at(7))
             ->method('execute')
             ->with($this->equalTo($this->getCmd("git checkout 'ref' && git reset --hard 'ref'")), $this->equalTo(null), $this->equalTo('composerPath'))
             ->will($this->returnValue(0));
@@ -159,6 +170,9 @@ class GitDownloaderTest extends \PHPUnit_Framework_TestCase
         $packageMock->expects($this->any())
             ->method('getSourceUrl')
             ->will($this->returnValue('https://github.com/composer/composer'));
+        $packageMock->expects($this->any())
+            ->method('getPrettyVersion')
+            ->will($this->returnValue('1.0.0'));
         $processExecutor = $this->getMock('Composer\Util\ProcessExecutor');
         $processExecutor->expects($this->at(0))
             ->method('execute')
@@ -173,6 +187,10 @@ class GitDownloaderTest extends \PHPUnit_Framework_TestCase
             ->with($this->equalTo($expectedGitUpdateCommand))
             ->will($this->returnValue(0));
         $processExecutor->expects($this->at(3))
+            ->method('execute')
+            ->with($this->equalTo('git branch -r'))
+            ->will($this->returnValue(0));
+        $processExecutor->expects($this->at(4))
             ->method('execute')
             ->with($this->equalTo($this->getCmd("git checkout 'ref' && git reset --hard 'ref'")), $this->equalTo(null), $this->equalTo('composerPath'))
             ->will($this->returnValue(0));