Merge pull request #9 from ianunruh/master

Added ability to check the size of a reference map

Author: jdantonio

lib/ref/abstract_reference_key_map.rb

@@ -32,6 +32,8 @@ def [](key)
       @values[rkey] if rkey
     end
 
+    alias_method :get, :[]
+
     # Add a key/value to the map.
     def []=(key, value)
       ObjectSpace.define_finalizer(key, @reference_cleanup)
@@ -41,6 +43,8 @@ def []=(key, value)
       end
     end
 
+    alias_method :put, :[]=
+
     # Remove the value associated with the key from the map.
     def delete(key)
       rkey = ref_key(key)
@@ -88,6 +92,24 @@ def merge!(other_hash)
       end
     end
 
+    # The number of entries in the map
+    def size
+      @references_to_keys_map.count do |_, ref|
+        ref.object
+      end
+    end
+
+    alias_method :length, :size
+
+    # True if there are entries that exist in the map
+    def empty?
+      @references_to_keys_map.each do |_, ref|
+        return false if ref.object
+      end
+
+      true
+    end
+
     def inspect
       live_entries = {}
       each do |key, value|

lib/ref/abstract_reference_value_map.rb

@@ -33,6 +33,8 @@ def [](key)
       value
     end
 
+    alias_method :get, :[]
+
     # Add a key/value to the map.
     def []=(key, value)
       ObjectSpace.define_finalizer(value, @reference_cleanup)
@@ -49,6 +51,8 @@ def []=(key, value)
       value
     end
 
+    alias_method :put, :[]=
+
     # Remove the entry associated with the key from the map.
     def delete(key)
       ref = @references.delete(key)
@@ -102,6 +106,24 @@ def merge!(other_hash)
       end
     end
 
+    # The number of entries in the map
+    def size
+      @references.count do |_, ref|
+        ref.object
+      end
+    end
+
+    alias_method :length, :size
+
+    # True if there are entries that exist in the map
+    def empty?
+      @references.each do |_, ref|
+        return false if ref.object
+      end
+
+      true
+    end
+
     def inspect
       live_entries = {}
       each do |key, value|

test/reference_key_map_behavior.rb

@@ -145,6 +145,23 @@ def test_can_iterate_over_all_entries
     end
   end
 
+  def test_size
+    Ref::Mock.use do
+      hash = map_class.new
+      assert hash.empty?
+      assert_equal 0, hash.size
+      key_1 = Object.new
+      key_2 = Object.new
+      hash[key_1] = "value 1"
+      hash[key_2] = "value 2"
+      refute hash.empty?
+      assert_equal 2, hash.size
+      Ref::Mock.gc(key_2)
+      refute hash.empty?
+      assert_equal 1, hash.size
+    end
+  end
+
   def test_inspect
     Ref::Mock.use do
       hash = map_class.new

test/reference_value_map_behavior.rb

@@ -125,6 +125,23 @@ def test_can_iterate_over_all_entries
     end
   end
 
+  def test_size
+    Ref::Mock.use do
+      hash = map_class.new
+      assert hash.empty?
+      assert_equal 0, hash.size
+      value_1 = "value 1"
+      value_2 = "value 2"
+      hash["key 1"] = value_1
+      hash["key 2"] = value_2
+      refute hash.empty?
+      assert_equal 2, hash.size
+      Ref::Mock.gc(value_2)
+      refute hash.empty?
+      assert_equal 1, hash.size
+    end
+  end
+
   def test_inspect
     Ref::Mock.use do
       hash = map_class.new