test argument handling and simplify cache keys

lib/cache_method.rb

@@ -20,15 +20,7 @@ def self.method_delimiter(obj) #:nodoc:
   def self.method_signature(obj, method_id) #:nodoc:
     [ klass_name(obj), method_id ].join method_delimiter(obj)
   end
-
-  # What gets called to determine the hashcode of an object.
-  #
-  # * If the object is a Class, then it just does Class.to_s (otherwise Class hash codes change too often)
-  # * Otherwise, call #hash
-  def self.hashcode(obj)
-    obj.is_a?(::Class) ? obj.to_s : obj.hash
-  end
-
+
   # All Objects, including instances and Classes, get the <tt>#clear_method_cache</tt> method.
   module InstanceMethods
     # Clear the cache for a particular method.
@@ -65,7 +57,7 @@ def cache_method(method_id, ttl = nil)
       original_method_id = "_uncached_#{method_id}"
       alias_method original_method_id, method_id
       define_method method_id do |*args|
-        ::CacheMethod::CachedResult.fetch :obj => self, :method_id => method_id, :original_method_id => original_method_id, :args => args, :ttl => ttl
+        ::CacheMethod::CachedResult.fetch :obj => self, :method_id => method_id, :original_method_id => original_method_id, :ttl => ttl, :args => args
       end
     end
   end

lib/cache_method/cached_result.rb

@@ -19,6 +19,7 @@ def initialize(options = {})
     attr_reader :original_method_id
     attr_reader :args
 
+    # Store things wrapped in an Array so that nil is accepted
     def fetch
       if v = Config.instance.storage.get(cache_key) and v.is_a?(::Array)
         v[0]
@@ -34,19 +35,23 @@ def ttl
     end
 
     def cache_key
-      [ 'CacheMethod', 'CachedResult', method_signature, current_epoch, obj_hash, args_digest ].join ','
+      if obj.is_a? ::Class
+        [ 'CacheMethod', 'CachedResult', method_signature, current_epoch, args_digest ].join ','
+      else
+        [ 'CacheMethod', 'CachedResult', method_signature, obj_hash, current_epoch, args_digest ].join ','
+      end
     end
 
     def method_signature
       @method_signature ||= ::CacheMethod.method_signature(obj, method_id)
     end
 
     def obj_hash
-      @obj_hash ||= ::CacheMethod.hashcode(obj)
+      @obj_hash ||= obj.hash
     end
 
     def args_digest
-      @args_digest ||= ::Digest::MD5.hexdigest(args.flatten.join)
+      @args_digest ||= args.empty? ? 'empty' : ::Digest::MD5.hexdigest(args.join)
     end
 
     def current_epoch

lib/cache_method/epoch.rb

@@ -1,4 +1,3 @@
-require 'digest/md5'
 module CacheMethod
   class Epoch #:nodoc: all
     class << self
@@ -13,7 +12,7 @@ def mark_passing(options = {})
       end
 
       def random_name
-        ::Digest::MD5.hexdigest rand.to_s
+        rand(1_000_000).to_s
       end
     end
 
@@ -31,11 +30,15 @@ def method_signature
     end
 
     def obj_hash
-      @obj_hash ||= ::CacheMethod.hashcode(obj)
+      @obj_hash ||= obj.hash
     end
 
     def cache_key
-      [ 'CacheMethod', 'Epoch', method_signature, obj_hash ].join ','
+      if obj.is_a? ::Class
+        [ 'CacheMethod', 'Epoch', method_signature ].join ','
+      else
+        [ 'CacheMethod', 'Epoch', method_signature, obj_hash ].join ','
+      end
     end
 
     def current

lib/cache_method/version.rb

@@ -1,3 +1,3 @@
 module CacheMethod
-  VERSION = "0.0.3"
+  VERSION = "0.1.0"
 end

test/helper.rb

@@ -19,9 +19,23 @@ def initialize(name)
   def echo_count
     @echo_count ||= 0
   end
+  # http://www.ruby-forum.com/topic/98106
+  # matz: "In 1.9, values (i.e. result of splat) are always represented by array,
+  #        so that we won't confuse array as an value with array as values
+  #        representation."
   def echo(*args)
     self.echo_count += 1
-    return *args
+    if RUBY_VERSION >= '1.9'
+      if args.empty?
+        return nil
+      elsif args.length == 1
+        return args[0]
+      else
+        return args
+      end
+    else
+      return *args
+    end
   end
   def hash
     name.hash
@@ -37,7 +51,17 @@ def echo_count
     end
     def echo(*args)
       self.echo_count += 1
-      return *args
+      if RUBY_VERSION >= '1.9'
+        if args.empty?
+          return nil
+        elsif args.length == 1
+          return args[0]
+        else
+          return args
+        end
+      else
+        return *args
+      end
     end
     cache_method :echo
   end

test/test_cache_method.rb

@@ -6,14 +6,39 @@ class TestCacheMethod < Test::Unit::TestCase
   def setup
     Blog2.request_count = 0
     CopyCat2.echo_count = 0
-    my_cache = Memcached.new '127.0.0.1:11211'
-    CacheMethod.config.storage = my_cache
+    my_cache = Memcached.new '127.0.0.1:11211', :binary => false
     my_cache.flush
+    CacheMethod.config.storage = my_cache
   end
 
   def test_cache_instance_method_with_args
     a = CopyCat1.new 'mimo'
 
+    assert_equal 'hi', a.echo('hi')
+    assert_equal 1, a.echo_count
+
+    assert_equal 'hi', a.echo('hi')
+    assert_equal 1, a.echo_count
+  end
+
+  def test_cache_instance_method_with_nil_args
+    a = CopyCat1.new 'mimo'
+    assert_equal nil, a.echo
+    assert_equal 1, a.echo_count
+
+    assert_equal nil, a.echo
+    assert_equal 1, a.echo_count
+
+    assert_equal nil, a.echo(nil)
+    assert_equal 2, a.echo_count
+
+    assert_equal nil, a.echo(nil)
+    assert_equal 2, a.echo_count    
+  end
+
+  def test_cache_instance_method_with_array_args
+    a = CopyCat1.new 'mimo'
+
     assert_equal ['hi'], a.echo(['hi'])
     assert_equal 1, a.echo_count
 
@@ -26,14 +51,43 @@ def test_cache_instance_method_with_args
     assert_equal ['bye'], a.echo(['bye'])
     assert_equal 2, a.echo_count
 
-    assert_equal nil, a.echo
+    assert_equal ['hi', 'there'], a.echo(['hi', 'there'])
     assert_equal 3, a.echo_count
 
-    assert_equal nil, a.echo
+    # same as previous
+    assert_equal ['hi', 'there'], a.echo('hi', 'there')
     assert_equal 3, a.echo_count
+
+    assert_equal [], a.echo([])
+    assert_equal 4, a.echo_count
+
+    assert_equal [], a.echo([])
+    assert_equal 4, a.echo_count
   end
-  
+
   def test_cache_class_method_with_args
+    assert_equal 'hi', CopyCat2.echo('hi')
+    assert_equal 1, CopyCat2.echo_count
+
+    assert_equal 'hi', CopyCat2.echo('hi')
+    assert_equal 1, CopyCat2.echo_count
+  end
+
+  def test_cache_class_method_with_nil_args
+    assert_equal nil, CopyCat2.echo
+    assert_equal 1, CopyCat2.echo_count
+
+    assert_equal nil, CopyCat2.echo
+    assert_equal 1, CopyCat2.echo_count
+
+    assert_equal nil, CopyCat2.echo(nil)
+    assert_equal 2, CopyCat2.echo_count
+
+    assert_equal nil, CopyCat2.echo(nil)
+    assert_equal 2, CopyCat2.echo_count    
+  end
+
+  def test_cache_class_method_with_array_args
     assert_equal ['hi'], CopyCat2.echo(['hi'])
     assert_equal 1, CopyCat2.echo_count
 
@@ -46,13 +100,19 @@ def test_cache_class_method_with_args
     assert_equal ['bye'], CopyCat2.echo(['bye'])
     assert_equal 2, CopyCat2.echo_count
 
-    assert_equal nil, CopyCat2.echo
+    assert_equal ['hi', 'there'], CopyCat2.echo(['hi', 'there'])
     assert_equal 3, CopyCat2.echo_count
 
-    assert_equal nil, CopyCat2.echo
+    assert_equal ['hi', 'there'], CopyCat2.echo('hi', 'there')
     assert_equal 3, CopyCat2.echo_count
+
+    assert_equal [], CopyCat2.echo([])
+    assert_equal 4, CopyCat2.echo_count
+
+    assert_equal [], CopyCat2.echo([])
+    assert_equal 4, CopyCat2.echo_count
   end
-
+    
   def test_cache_instance_method
     a = new_instance_of_my_blog
     assert_equal ["hello from #{a.name}"], a.get_latest_entries