From a23282dcc68596f1b6de549e722b3ab468fc02ed Mon Sep 17 00:00:00 2001
From: Nick Elser <nick.elser@gmail.com>
Date: Thu, 7 May 2015 00:16:28 -0700
Subject: [PATCH] don't go around allocating empty strings willy-nilly

---
 CHANGELOG.md                | 4 ++++
 README.md                   | 6 +++---
 lib/suo/client/base.rb      | 8 ++++++--
 lib/suo/client/memcached.rb | 2 +-
 lib/suo/client/redis.rb     | 6 ++++--
 lib/suo/version.rb          | 2 +-
 6 files changed, 19 insertions(+), 9 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 0a155cb..d4add84 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,7 @@
+## 0.3.1
+
+- Slight memory leak fix.
+
 ## 0.3.0
 
 - Dramatically simplify the interface by forcing clients to specify the key & resources at lock initialization instead of every method call.
diff --git a/README.md b/README.md
index dd6bc64..4f2420c 100644
--- a/README.md
+++ b/README.md
@@ -34,7 +34,7 @@ end
 # The resources argument is the number of resources the semaphore will allow to lock (defaulting to one - a mutex)
 suo = Suo::Client::Memcached.new("bar_resource", client: some_dalli_client, resources: 2)
 
-Thread.new { suo.lock{ puts "One"; sleep 2 } }
+Thread.new { suo.lock { puts "One"; sleep 2 } }
 Thread.new { suo.lock { puts "Two"; sleep 2 } }
 Thread.new { suo.lock { puts "Three" } }
 
@@ -46,7 +46,7 @@ suo = Suo::Client::Memcached.new("protected_key", client: some_dalli_client, acq
 # manually locking/unlocking
 # the return value from lock without a block is a unique token valid only for the current lock
 # which must be unlocked manually
-token = suo
+token = suo.lock
 foo.baz!
 suo.unlock(token)
 
@@ -77,7 +77,7 @@ end
 
 ## History
 
-View the [changelog](https://github.com/nickelser/suo/blob/master/CHANGELOG.md)
+View the [changelog](https://github.com/nickelser/suo/blob/master/CHANGELOG.md).
 
 ## Contributing
 
diff --git a/lib/suo/client/base.rb b/lib/suo/client/base.rb
index 7d74810..5444631 100644
--- a/lib/suo/client/base.rb
+++ b/lib/suo/client/base.rb
@@ -8,17 +8,21 @@ class Base
         resources: 1
       }.freeze
 
+      BLANK_STR = "".freeze
+
       attr_accessor :client, :key, :resources, :options
 
       include MonitorMixin
 
       def initialize(key, options = {})
         fail "Client required" unless options[:client]
+
         @options = DEFAULT_OPTIONS.merge(options)
         @retry_count = (@options[:acquisition_timeout] / @options[:acquisition_delay].to_f).ceil
         @client = @options[:client]
         @resources = @options[:resources].to_i
         @key = key
+
         super() # initialize Monitor mixin for thread safety
       end
 
@@ -124,7 +128,7 @@ def set(newval, cas) # rubocop:disable Lint/UnusedMethodArgument
         fail NotImplementedError
       end
 
-      def initial_set(val = "") # rubocop:disable Lint/UnusedMethodArgument
+      def initial_set(val = BLANK_STR) # rubocop:disable Lint/UnusedMethodArgument
         fail NotImplementedError
       end
 
@@ -158,7 +162,7 @@ def deserialize_and_clear_locks(val)
       end
 
       def deserialize_locks(val)
-        unpacked = (val.nil? || val == "") ? [] : MessagePack.unpack(val)
+        unpacked = (val.nil? || val == BLANK_STR) ? [] : MessagePack.unpack(val)
 
         unpacked.map do |time, token|
           [Time.at(time), token]
diff --git a/lib/suo/client/memcached.rb b/lib/suo/client/memcached.rb
index 7f87020..83b37b6 100644
--- a/lib/suo/client/memcached.rb
+++ b/lib/suo/client/memcached.rb
@@ -20,7 +20,7 @@ def set(newval, cas)
         @client.set_cas(@key, newval, cas)
       end
 
-      def initial_set(val = "")
+      def initial_set(val = BLANK_STR)
         @client.set(@key, val)
       end
     end
diff --git a/lib/suo/client/redis.rb b/lib/suo/client/redis.rb
index 439e868..b13119e 100644
--- a/lib/suo/client/redis.rb
+++ b/lib/suo/client/redis.rb
@@ -1,6 +1,8 @@
 module Suo
   module Client
     class Redis < Base
+      OK_STR = "OK".freeze
+
       def initialize(key, options = {})
         options[:client] ||= ::Redis.new(options[:connection] || {})
         super
@@ -21,7 +23,7 @@ def set(newval, _)
           multi.set(@key, newval)
         end
 
-        ret && ret[0] == "OK"
+        ret && ret[0] == OK_STR
       end
 
       def synchronize
@@ -32,7 +34,7 @@ def synchronize
         @client.unwatch
       end
 
-      def initial_set(val = "")
+      def initial_set(val = BLANK_STR)
         @client.set(@key, val)
       end
     end
diff --git a/lib/suo/version.rb b/lib/suo/version.rb
index 32cd83c..523c7c6 100644
--- a/lib/suo/version.rb
+++ b/lib/suo/version.rb
@@ -1,3 +1,3 @@
 module Suo
-  VERSION = "0.3.0"
+  VERSION = "0.3.1"
 end