Added another testcase + fix

src/Composer/Package/Version/VersionParser.php

@@ -425,7 +425,7 @@ class VersionParser
                 $upperBound = new VersionConstraint('<=', $highVersion);
             } else {
                 $highMatch = array('', $matches[10], $matches[11], $matches[12], $matches[13]);
-                $highVersion = $this->manipulateVersionString($highMatch, empty($matches[11]) ? 1 : 2, 1) . '-dev';
+                $highVersion = $this->manipulateVersionString($highMatch, $empty($matches[11]) ? 1 : 2, 1) . '-dev';
                 $upperBound = new VersionConstraint('<', $highVersion);
             }
 

tests/Composer/Test/Package/Version/VersionParserTest.php

@@ -380,9 +380,10 @@ class VersionParserTest extends \PHPUnit_Framework_TestCase
             array('1.2-beta - 2.3-dev',   new VersionConstraint('>=', '1.2.0.0-beta'),  new VersionConstraint('<=', '2.3.0.0-dev')),
             array('1.2-RC - 2.3.1',       new VersionConstraint('>=', '1.2.0.0-RC'),    new VersionConstraint('<=', '2.3.1.0')),
             array('1.2.3-alpha - 2.3-RC', new VersionConstraint('>=', '1.2.3.0-alpha'), new VersionConstraint('<=', '2.3.0.0-RC')),
+            array('1 - 2.0',              new VersionConstraint('>=', '1.0.0.0-dev'),   new VersionConstraint('<', '2.1.0.0-dev')),
             array('1 - 2.1',              new VersionConstraint('>=', '1.0.0.0-dev'),   new VersionConstraint('<', '2.2.0.0-dev')),
             array('1.2 - 2.1.0',          new VersionConstraint('>=', '1.2.0.0-dev'),   new VersionConstraint('<=', '2.1.0.0')),
-            array('1.2 - 2.1.3',          new VersionConstraint('>=', '1.2.0.0-dev'),   new VersionConstraint('<=', '2.1.3.0')),
+            array('1.3 - 2.1.3',          new VersionConstraint('>=', '1.3.0.0-dev'),   new VersionConstraint('<=', '2.1.3.0')),
         );
     }