Fixed a problem where referencing a relative file path in a ruleset XML file could add unnecessary sniff exclusions

Author: gsherwood

package.xml

@@ -34,6 +34,8 @@ http://pear.php.net/dtd/package-2.0.xsd">
   - The Squiz standard now ensures underscores are not used to indicate visibility of private members vars and methods
     -- Previously, this standard enforced the use of underscores
   - Squiz.Commenting.FunctionComment no longer errors when trying to fix indents of multi-line param comments
+  - Fixed a problem where referencing a relative file path in a ruleset XML file could add unnecessary sniff exclusions
+    -- This didn't actually exclude anything, but caused verbose output to list strange exclusion rules
   - Fixed bug #2110 : Squiz.WhiteSpace.FunctionSpacing is removing indents from the start of functions when fixing
     -- Thanks to Juliette Reinders Folmer for the patch
   - Fixed bug #2115 : Squiz.Commenting.VariableComment not checking var types when the @var line contains a comment

src/Ruleset.php

@@ -390,7 +390,11 @@ public function processRuleset($rulesetPath, $depth=0)
             $includedSniffs = array_merge($includedSniffs, $expandedSniffs);
 
             $parts = explode('.', $rule['ref']);
-            if (count($parts) === 4) {
+            if (count($parts) === 4
+                && $parts[0] !== ''
+                && $parts[1] !== ''
+                && $parts[2] !== ''
+            ) {
                 $sniffCode = $parts[0].'.'.$parts[1].'.'.$parts[2];
                 if (isset($this->ruleset[$sniffCode]['severity']) === true
                     && $this->ruleset[$sniffCode]['severity'] === 0