Added Relationship#child_model? and #parent_model?

* It is useful to test whether a model is defined before carrying out some actions. * When comparing models between relationships only compare cases where both models are defined.
datamapper · Jul 2, 2009 · 2cab5a0 · 2cab5a0
1 parent e085aa7
commit 2cab5a0
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Showing 3 changed files with 60 additions and 1 deletion.
diff --git a/lib/dm-core/associations/many_to_one.rb b/lib/dm-core/associations/many_to_one.rb
@@ -14,10 +14,18 @@ class Relationship < Associations::Relationship
         # @api semipublic
         alias source_model child_model
 
+        # TODO: document
+        # @api semipublic
+        alias source_model? child_model?
+
         # TODO: document
         # @api semipublic
         alias source_key child_key
 
+        # TODO: document
+        # @api semipublic
+        alias source_key? child_key?
+
         # TODO: document
         # @api semipublic
         alias target_repository_name parent_repository_name
@@ -26,10 +34,18 @@ class Relationship < Associations::Relationship
         # @api semipublic
         alias target_model parent_model
 
+        # TODO: document
+        # @api semipublic
+        alias target_model? parent_model?
+
         # TODO: document
         # @api semipublic
         alias target_key parent_key
 
+        # TODO: document
+        # @api semipublic
+        alias target_key? parent_key?
+
         # TODO: document
         # @api semipublic
         def nullable?

diff --git a/lib/dm-core/associations/one_to_many.rb b/lib/dm-core/associations/one_to_many.rb
@@ -10,10 +10,18 @@ class Relationship < Associations::Relationship
         # @api semipublic
         alias target_model child_model
 
+        # TODO: document
+        # @api semipublic
+        alias target_model? child_model?
+
         # TODO: document
         # @api semipublic
         alias target_key child_key
 
+        # TODO: document
+        # @api semipublic
+        alias target_key? child_key?
+
         # TODO: document
         # @api semipublic
         alias source_repository_name parent_repository_name
@@ -22,10 +30,18 @@ class Relationship < Associations::Relationship
         # @api semipublic
         alias source_model parent_model
 
+        # TODO: document
+        # @api semipublic
+        alias source_model? parent_model?
+
         # TODO: document
         # @api semipublic
         alias source_key parent_key
 
+        # TODO: document
+        # @api semipublic
+        alias source_key? parent_key?
+
         ##
         # Returns a Collection for this relationship with a given source
         #

diff --git a/lib/dm-core/associations/relationship.rb b/lib/dm-core/associations/relationship.rb
@@ -145,6 +145,15 @@ def child_model
         raise NameError, "Cannot find the child_model #{child_model_name} for #{parent_model_name} in #{name}"
       end
 
+      # TODO: document
+      # @api private
+      def child_model?
+        child_model
+        true
+      rescue NameError
+        false
+      end
+
       # TODO: document
       # @api private
       def child_model_name
@@ -197,6 +206,15 @@ def parent_model
         raise NameError, "Cannot find the parent_model #{parent_model_name} for #{child_model_name} in #{name}"
       end
 
+      # TODO: document
+      # @api private
+      def parent_model?
+        parent_model
+        true
+      rescue NameError
+        false
+      end
+
       # TODO: document
       # @api private
       def parent_model_name
@@ -585,7 +603,16 @@ def cmp_repository?(other, type, operator = :==)
       # TODO: document
       # @api private
       def cmp_model?(other, type, operator = :==)
-        method = "#{type}_model".to_sym
+        method  = "#{type}_model".to_sym
+        defined = "#{method}?".to_sym
+
+        unless send(defined)
+          return false
+        end
+
+        unless other.send(defined)
+          return false
+        end
 
         unless send(method).send(operator, other.send(method))
           return false