Some changes as suggested in the pr

src/Composer/Repository/Vcs/HgDriver.php

@@ -172,11 +172,15 @@ class HgDriver implements VcsDriverInterface
      */
     public static function supports($url, $deep = false)
     {
-	    if ($deep) {
-		    exec(sprintf('hg identify %s', escapeshellarg($url)), $outputIgnored, $exit);
-		    return $exit == 0;
-	    }
+        if (preg_match('#(^(?:https?|ssh)://(?:[^@]@)?bitbucket.org|https://(?:.*?)\.kilnhg.com)#i', $url)) {
+            return true;
+        }
+        
+        if (!$deep) {
+            return false;
+        }
 
-	    return false;
+        exec(sprintf('hg identify %s', escapeshellarg($url)), null, $exit);
+        return $exit == 0;
     }
 }

src/Composer/Repository/Vcs/SvnDriver.php

@@ -174,11 +174,11 @@ class SvnDriver implements VcsDriverInterface
             return true;
         }
 
-        if ($deep) {
-	        @exec(sprintf('svn info --non-interactive %s 2>/dev/null', escapeshellarg($url)), $outputIgnored, $exit);
-	        return $exit == 0;
+        if (!$deep) {
+            return false;
         }
-
-	    return false;
+        
+        @exec(sprintf('svn info --non-interactive %s 2>/dev/null', escapeshellarg($url)), null, $exit);
+        return $exit == 0;
     }
 }