diff --git a/src/Composer/Package/Loader/RootPackageLoader.php b/src/Composer/Package/Loader/RootPackageLoader.php
index d384b1751..04b44f7b6 100644
--- a/src/Composer/Package/Loader/RootPackageLoader.php
+++ b/src/Composer/Package/Loader/RootPackageLoader.php
@@ -68,22 +68,25 @@ class RootPackageLoader extends ArrayLoader
         }
         $autoVersioned = false;
         if (!isset($config['version'])) {
+            $commit = null;
+
             // override with env var if available
             if (getenv('COMPOSER_ROOT_VERSION')) {
-                $version = getenv('COMPOSER_ROOT_VERSION');
-                $commit = null;
+                $config['version'] = getenv('COMPOSER_ROOT_VERSION');
             } else {
                 $versionData = $this->versionGuesser->guessVersion($config, $cwd ?: getcwd());
-                $version = $versionData['version'];
-                $commit = $versionData['commit'];
+                if ($versionData) {
+                    $config['version'] = $versionData['pretty_version'];
+                    $config['version_normalized'] = $versionData['version'];
+                    $commit = $versionData['commit'];
+                }
             }
 
-            if (!$version) {
-                $version = '1.0.0';
+            if (!isset($config['version'])) {
+                $config['version'] = '1.0.0';
                 $autoVersioned = true;
             }
 
-            $config['version'] = $version;
             if ($commit) {
                 $config['source'] = array(
                     'type' => '',
diff --git a/src/Composer/Package/Version/VersionGuesser.php b/src/Composer/Package/Version/VersionGuesser.php
index ffa5583dd..f8e43fb88 100644
--- a/src/Composer/Package/Version/VersionGuesser.php
+++ b/src/Composer/Package/Version/VersionGuesser.php
@@ -59,30 +59,43 @@ class VersionGuesser
      * @param array  $packageConfig
      * @param string $path          Path to guess into
      *
-     * @return array versionData, 'version', 'pretty_version' and 'commit' keys
+     * @return null|array versionData, 'version', 'pretty_version' and 'commit' keys
      */
     public function guessVersion(array $packageConfig, $path)
     {
         if (function_exists('proc_open')) {
             $versionData = $this->guessGitVersion($packageConfig, $path);
             if (null !== $versionData && null !== $versionData['version']) {
-                return $versionData;
+                return $this->postprocess($versionData);
             }
 
             $versionData = $this->guessHgVersion($packageConfig, $path);
             if (null !== $versionData && null !== $versionData['version']) {
-                return $versionData;
+                return $this->postprocess($versionData);
             }
 
             $versionData = $this->guessFossilVersion($packageConfig, $path);
             if (null !== $versionData && null !== $versionData['version']) {
-                return $versionData;
+                return $this->postprocess($versionData);
             }
 
-            return $this->guessSvnVersion($packageConfig, $path);
+            $versionData = $this->guessSvnVersion($packageConfig, $path);
+            if (null !== $versionData && null !== $versionData['version']) {
+                return $this->postprocess($versionData);
+            }
         }
     }
 
+    private function postprocess(array $versionData)
+    {
+        // make sure that e.g. dev-1.5 gets converted to 1.5.x-dev
+        if ('dev-' !== substr($versionData['version'], 0, 4)) {
+            $versionData['pretty_version'] = preg_replace('{(\.9{7})+}', '.x', $versionData['version']);
+        }
+
+        return $versionData;
+    }
+
     private function guessGitVersion(array $packageConfig, $path)
     {
         GitUtil::cleanEnv();
diff --git a/src/Composer/Repository/Vcs/GitLabDriver.php b/src/Composer/Repository/Vcs/GitLabDriver.php
index 45cdac717..b883eefea 100644
--- a/src/Composer/Repository/Vcs/GitLabDriver.php
+++ b/src/Composer/Repository/Vcs/GitLabDriver.php
@@ -311,7 +311,7 @@ class GitLabDriver extends VcsDriver
         if (isset($this->project['visibility'])) {
             $this->isPrivate = $this->project['visibility'] !== 'public';
         } else {
-            // client is not authendicated, therefore repository has to be public 
+            // client is not authendicated, therefore repository has to be public
             $this->isPrivate = false;
         }
     }
@@ -351,7 +351,7 @@ class GitLabDriver extends VcsDriver
 
     protected function generatePublicUrl()
     {
-        return 'https://' . $this->originUrl . '/'.$this->namespace.'/'.$this->repository.'.git';
+        return $this->scheme . '://' . $this->originUrl . '/'.$this->namespace.'/'.$this->repository.'.git';
     }
 
     protected function setupGitDriver($url)
diff --git a/tests/Composer/Test/Package/Loader/RootPackageLoaderTest.php b/tests/Composer/Test/Package/Loader/RootPackageLoaderTest.php
index 951645971..7a46b4992 100644
--- a/tests/Composer/Test/Package/Loader/RootPackageLoaderTest.php
+++ b/tests/Composer/Test/Package/Loader/RootPackageLoaderTest.php
@@ -17,6 +17,7 @@ use Composer\Package\Loader\RootPackageLoader;
 use Composer\Package\BasePackage;
 use Composer\Package\Version\VersionGuesser;
 use Composer\Semver\VersionParser;
+use Prophecy\Argument;
 
 class RootPackageLoaderTest extends \PHPUnit_Framework_TestCase
 {
@@ -91,6 +92,26 @@ class RootPackageLoaderTest extends \PHPUnit_Framework_TestCase
         $this->assertEquals("No version set (parsed as 1.0.0)", $package->getPrettyVersion());
     }
 
+    public function testPrettyVersionForRootPackageInVersionBranch()
+    {
+        // see #6845
+        $manager = $this->prophesize('\\Composer\\Repository\\RepositoryManager');
+        $versionGuesser = $this->prophesize('\\Composer\\Package\\Version\\VersionGuesser');
+        $versionGuesser->guessVersion(Argument::cetera())
+            ->willReturn(array(
+                'name' => 'A',
+                'version' => '3.0.9999999.9999999-dev',
+                'pretty_version' => '3.0-dev',
+                'commit' => 'aabbccddee',
+            ));
+        $config = new Config;
+        $config->merge(array('repositories' => array('packagist' => false)));
+        $loader = new RootPackageLoader($manager->reveal(), $config, null, $versionGuesser->reveal());
+        $package = $loader->load(array());
+
+        $this->assertEquals('3.0-dev', $package->getPrettyVersion());
+    }
+
     public function testFeatureBranchPrettyVersion()
     {
         if (!function_exists('proc_open')) {
diff --git a/tests/Composer/Test/Package/Version/VersionGuesserTest.php b/tests/Composer/Test/Package/Version/VersionGuesserTest.php
index 60681393c..fafb81c33 100644
--- a/tests/Composer/Test/Package/Version/VersionGuesserTest.php
+++ b/tests/Composer/Test/Package/Version/VersionGuesserTest.php
@@ -412,4 +412,35 @@ class VersionGuesserTest extends \PHPUnit_Framework_TestCase
 
         $this->assertEquals("dev-foo", $versionData['version']);
     }
+
+    public function testNumericBranchesShowNicely()
+    {
+        $executor = $this->getMockBuilder('\\Composer\\Util\\ProcessExecutor')
+            ->setMethods(array('execute'))
+            ->disableArgumentCloning()
+            ->disableOriginalConstructor()
+            ->getMock()
+        ;
+
+        $self = $this;
+
+        $executor
+            ->expects($this->at(0))
+            ->method('execute')
+            ->willReturnCallback(function ($command, &$output) use ($self) {
+                $self->assertEquals('git branch --no-color --no-abbrev -v', $command);
+                $output = "* 1.5 03a15d220da53c52eddd5f32ffca64a7b3801bea Commit message\n";
+
+                return 0;
+            })
+        ;
+
+        $config = new Config;
+        $config->merge(array('repositories' => array('packagist' => false)));
+        $guesser = new VersionGuesser($config, $executor, new VersionParser());
+        $versionData = $guesser->guessVersion(array(), 'dummy/path');
+
+        $this->assertEquals("1.5.x-dev", $versionData['pretty_version']);
+        $this->assertEquals("1.5.9999999.9999999-dev", $versionData['version']);
+    }
 }