Aliased fields now work with distinct queries.

[ fix mongoid/moped#82 ]

CHANGELOG.md

@@ -110,6 +110,8 @@ For instructions on upgrading to newer versions, visit
 
 ### Resolved Issues
 
+* mongoid/moped\#82 Aliased fields now work with `Criteria#distinct`.
+
 * \#2423 Fixed embedded document's `update_all` to perform the correct $set
   when using off a criteria.
 

lib/mongoid/contextual/mongo.rb

@@ -97,7 +97,7 @@ def destroy
       #
       # @since 3.0.0
       def distinct(field)
-        query.distinct(field)
+        query.distinct(klass.database_field_name(field))
       end
 
       # Iterate over the context. If provided a block, yield to a Mongoid

lib/mongoid/fields.rb

@@ -108,6 +108,21 @@ def attribute_names
       self.class.attribute_names
     end
 
+    # Get the name of the provided field as it is stored in the database.
+    # Used in determining if the field is aliased or not.
+    #
+    # @example Get the database field name.
+    #   model.database_field_name(:authorization)
+    #
+    # @param [ String, Symbol ] name The name to get.
+    #
+    # @return [ String ] The name of the field as it's stored in the db.
+    #
+    # @since 3.0.7
+    def database_field_name(name)
+      self.class.database_field_name(name)
+    end
+
     # Is the provided field a lazy evaluation?
     #
     # @example If the field is lazy settable.
@@ -189,6 +204,22 @@ def attribute_names
         fields.keys
       end
 
+      # Get the name of the provided field as it is stored in the database.
+      # Used in determining if the field is aliased or not.
+      #
+      # @example Get the database field name.
+      #   Model.database_field_name(:authorization)
+      #
+      # @param [ String, Symbol ] name The name to get.
+      #
+      # @return [ String ] The name of the field as it's stored in the db.
+      #
+      # @since 3.0.7
+      def database_field_name(name)
+        normalized = name.to_s
+        aliased_fields[normalized] || normalized
+      end
+
       # Defines all the fields that are accessible on the Document
       # For each field that is defined, a getter and setter will be
       # added as an instance method to the Document.

lib/mongoid/indexes.rb

@@ -115,10 +115,9 @@ def normalize_index_options(options)
       #
       # @since 3.0.7
       def normalize_spec(spec)
-        spec.inject({}) do |normal, (name, direction)|
-          field_name = aliased_fields[name.to_s] || name
-          normal[field_name.to_sym] = direction
-          normal
+        spec.inject({}) do |normalized, (name, direction)|
+          normalized[database_field_name(name).to_sym] = direction
+          normalized
         end
       end
     end

lib/mongoid/multi_parameter_attributes.rb

@@ -66,7 +66,7 @@ def process_attributes(attrs = nil, role = :default, guard_protected_attributes
         multi_parameter_attributes.each_pair do |key, values|
           begin
             values = (values.keys.min..values.keys.max).map { |i| values[i] }
-            field = self.class.fields[aliased_fields[key] || key]
+            field = self.class.fields[database_field_name(key)]
             attributes[key] = instantiate_object(field, values)
           rescue => e
             errors << Errors::AttributeAssignmentError.new(

lib/mongoid/persistence.rb

@@ -159,7 +159,7 @@ def update_attribute(name, value)
       unless attribute_writable?(normalized)
         raise Errors::ReadonlyAttribute.new(normalized, value)
       end
-      write_attribute(aliased_fields[normalized] || normalized, value)
+      write_attribute(database_field_name(normalized), value)
       save(validate: false)
     end
 

lib/mongoid/validations/uniqueness.rb

@@ -167,8 +167,7 @@ def filter(value)
       # @since 2.3.0
       def scope(criteria, document, attribute)
         Array.wrap(options[:scope]).each do |item|
-          normalized = item.to_s
-          name = document.aliased_fields[normalized] || normalized
+          name = document.database_field_name(item)
           criteria = criteria.where(item => document.attributes[name])
         end
         criteria = criteria.where(deleted_at: nil) if document.paranoid?

spec/app/models/band.rb

@@ -12,6 +12,7 @@ class Band
   field :upserted, type: Boolean, default: false
   field :created, type: DateTime
   field :sales, type: BigDecimal
+  field :y, as: :years, type: Integer
 
   embeds_many :records, cascade_callbacks: true
   embeds_many :notes, as: :noteable, cascade_callbacks: true, validate: false

spec/mongoid/contextual/mongo_spec.rb

@@ -256,8 +256,8 @@
   describe "#distinct" do
 
     before do
-      Band.create(name: "Depeche Mode")
-      Band.create(name: "New Order")
+      Band.create(name: "Depeche Mode", years: 30)
+      Band.create(name: "New Order", years: 25)
     end
 
     context "when limiting the result set" do
@@ -289,6 +289,21 @@
         context.distinct(:name).should eq([ "Depeche Mode", "New Order" ])
       end
     end
+
+    context "when providing an aliased field" do
+
+      let(:criteria) do
+        Band.criteria
+      end
+
+      let(:context) do
+        described_class.new(criteria)
+      end
+
+      it "returns the distinct field values" do
+        context.distinct(:years).should eq([ 30, 25 ])
+      end
+    end
   end
 
   describe "#each" do