Use fail instead of raise to signal exceptions

lib/yardstick/config.rb

@@ -116,7 +116,7 @@ def for_rule(rule_class)
       if key
         RuleConfig.new(@rules.fetch(key.to_sym, {}))
       else
-        raise InvalidRule, "every rule must begin with #{NAMESPACE_PREFIX}"
+        fail InvalidRule, "every rule must begin with #{NAMESPACE_PREFIX}"
       end
     end
 

lib/yardstick/rake/verify.rb

@@ -91,7 +91,7 @@ def define
       # @api private
       def assert_threshold
         unless @threshold
-          raise 'threshold must be set'
+          fail 'threshold must be set'
         end
       end
 
@@ -105,7 +105,7 @@ def assert_threshold
       # @api private
       def assert_meets_threshold
         if lower_coverage?
-          raise "YARD-Coverage must be at least #{@threshold}% but was #{total_coverage}%"
+          fail "YARD-Coverage must be at least #{@threshold}% but was #{total_coverage}%"
         end
       end
 
@@ -119,7 +119,7 @@ def assert_meets_threshold
       # @api private
       def assert_matches_threshold
         if @config.require_exact_threshold? && higher_coverage?
-          raise "YARD-Coverage has increased above the threshold of #{@threshold}% to #{total_coverage}%. You should update your threshold value."
+          fail "YARD-Coverage has increased above the threshold of #{@threshold}% to #{total_coverage}%. You should update your threshold value."
         end
       end