MONGOID-4935 Fix Errors::InvalidField gives the wrong method name in description (#5287)

* MONGOID-4935 Fix Errors::InvalidField gives the wrong method name in description

* MONGOID-4935 fix invalid field spec

* MONGOID-4935 fix message, add api private

Author: neilshweky

lib/config/locales/en.yml

@@ -138,7 +138,7 @@ en:
           resolution: "Valid expression operators are: %{valid_operators}.
             Ensure you are using one of these operators."
         invalid_field:
-          message: "Defining a field named '%{name}' is not allowed."
+          message: "Defining a field named '%{field}' is not allowed."
           summary: "Defining this field would override the method '%{name}',
             which would cause issues with expectations around the original
             method and cause extremely hard to debug issues. The original

lib/mongoid/errors/invalid_field.rb

@@ -12,14 +12,18 @@ class InvalidField < MongoidError
       # @example Create the error.
       #   InvalidField.new(person, :crazy_method_name)
       #
+      # @api private
+      #
       # @param [ Class ] klass The document class.
+      # @param [ Symbol ] field The field name.
       # @param [ Symbol ] name The method name.
-      def initialize(klass, name)
+      def initialize(klass, field, name)
         super(
           compose_message(
             "invalid_field",
             {
               name: name,
+              field: field,
               origin: origin(klass, name),
               file: location(klass, name)[0],
               line: location(klass, name)[1]

lib/mongoid/fields/validators/macro.rb

@@ -66,7 +66,7 @@ def validate_relation(klass, name, options = {})
         def validate_field_name(klass, name)
           [name, "#{name}?".to_sym, "#{name}=".to_sym].each do |n|
             if Mongoid.destructive_fields.include?(n)
-              raise Errors::InvalidField.new(klass, n)
+              raise Errors::InvalidField.new(klass, name, n)
             end
           end
         end
@@ -88,7 +88,7 @@ def validate_field_name(klass, name)
         def validate_name_uniqueness(klass, name, options)
           if !options[:overwrite] && klass.fields.keys.include?(name.to_s)
             if Mongoid.duplicate_fields_exception
-              raise Errors::InvalidField.new(klass, name)
+              raise Errors::InvalidField.new(klass, name, name)
             else
               Mongoid.logger.warn("Overwriting existing field #{name} in class #{klass.name}.") if Mongoid.logger
             end

spec/mongoid/errors/invalid_field_spec.rb

@@ -15,7 +15,7 @@ def crazy_method; self; end
     end
 
     let(:error) do
-      described_class.new(Person, :crazy_method)
+      described_class.new(Person, :crazy_method, :crazy_method)
     end
 
     it "contains the problem in the message" do

spec/mongoid/fields_spec.rb

@@ -877,7 +877,7 @@
           it "raises an error" do
             expect {
               Person.field(meth)
-            }.to raise_error(Mongoid::Errors::InvalidField)
+            }.to raise_error(Mongoid::Errors::InvalidField, /Defining a field named '#{meth}' is not allowed/)
           end
         end
       end