don't go around allocating empty strings willy-nilly

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.

README.md

@@ -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
 

lib/suo/client/base.rb

@@ -8,17 +8,21 @@ module Suo
         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 @@ module Suo
         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 @@ module Suo
       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]

lib/suo/client/memcached.rb

@@ -20,7 +20,7 @@ module Suo
         @client.set_cas(@key, newval, cas)
       end
 
-      def initial_set(val = "")
+      def initial_set(val = BLANK_STR)
         @client.set(@key, val)
       end
     end

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 @@ module Suo
           multi.set(@key, newval)
         end
 
-        ret && ret[0] == "OK"
+        ret && ret[0] == OK_STR
       end
 
       def synchronize
@@ -32,7 +34,7 @@ module Suo
         @client.unwatch
       end
 
-      def initial_set(val = "")
+      def initial_set(val = BLANK_STR)
         @client.set(@key, val)
       end
     end

lib/suo/version.rb

@@ -1,3 +1,3 @@
 module Suo
-  VERSION = "0.3.0"
+  VERSION = "0.3.1"
 end