From 76edeac34aad174d4ff3b11eb79031ab96201f28 Mon Sep 17 00:00:00 2001
From: Gavin Laking <gavinlaking@gmail.com>
Date: Fri, 29 Jan 2016 00:24:50 +0000
Subject: [PATCH] Do not measure timing if debugging is disabled or no block of
 code was given.

---
 lib/vedeu/logging/timer.rb           | 26 +++++++++++++++++---------
 test/lib/vedeu/logging/timer_test.rb | 12 +++++++++++-
 2 files changed, 28 insertions(+), 10 deletions(-)

diff --git a/lib/vedeu/logging/timer.rb b/lib/vedeu/logging/timer.rb
index d99045ab8..23100849d 100644
--- a/lib/vedeu/logging/timer.rb
+++ b/lib/vedeu/logging/timer.rb
@@ -33,24 +33,30 @@ def initialize(message = '')
       end
 
       # Write an entry to the log file stating how long a section of
-      # code took in milliseconds. Useful for debugging performance.
+      # code took in milliseconds when debugging is enabled and a
+      # block was Useful for debugging performance.
       #
       # @param block [Proc]
       # @macro raise_requires_block
-      # @return [void] The return value of the executed block.
+      # @return [void|NilClass] The return value of the executed
+      #   block if given, or nil if debugging is disabled.
       def measure(&block)
-        fail Vedeu::Error::RequiresBlock unless block_given?
+        if block_given?
+          if Vedeu.config.debug?
+            work = yield
 
-        if Vedeu.config.debug?
-          work = yield
+            Vedeu.log(type:    :timer,
+                      message: "#{message} took #{elapsed}ms.")
 
-          Vedeu.log(type:    :timer,
-                    message: "#{message} took #{elapsed}ms.")
+            work
 
-          work
+          else
+            yield
+
+          end
 
         else
-          yield
+          fail Vedeu::Error::RequiresBlock if Vedeu.config.debug?
 
         end
       end
@@ -65,6 +71,8 @@ def measure(&block)
       # @return [String]
       attr_reader :message
 
+      private
+
       # Returns the elapsed time in milliseconds with 3 decimal
       # places.
       #
diff --git a/test/lib/vedeu/logging/timer_test.rb b/test/lib/vedeu/logging/timer_test.rb
index 048a9734b..5a91bb2ff 100644
--- a/test/lib/vedeu/logging/timer_test.rb
+++ b/test/lib/vedeu/logging/timer_test.rb
@@ -51,7 +51,17 @@ module Logging
         context 'when the block is not given' do
           subject { instance.measure }
 
-          it { proc { subject }.must_raise(Vedeu::Error::RequiresBlock) }
+          context 'when debugging is enabled' do
+            before { Vedeu.config.stubs(:debug?).returns(true) }
+
+            it { proc { subject }.must_raise(Vedeu::Error::RequiresBlock) }
+          end
+
+          context 'when debugging is disabled' do
+            before { Vedeu.config.stubs(:debug?).returns(false) }
+
+            it { subject.must_equal(nil) }
+          end
         end
       end