ModelAttribute: Add `.methods_by_class_and_type` method

This enables filtering by class like `.methods_by_class` and
additionally only selecting attributes matching a certain data type.

Refs #4401

2 files changed, 21 insertions, 0 deletions

diff --git a/lib/model_attribute.rb b/lib/model_attribute.rb
index 84706ba4d..e74dd1060 100644
--- a/lib/model_attribute.rb
+++ b/lib/model_attribute.rb
@@ -15,6 +15,12 @@ class ModelAttribute
     end
   end
 
+  def self.methods_by_class_and_type(klass, type)
+    methods_by_class(klass).select do |model_attr|
+      model_attr.data_type == type
+    end
+  end
+
   def initialize(klass, name, data_type)
     @klass = klass
     @name = name
diff --git a/spec/lib/model_attribute_spec.rb b/spec/lib/model_attribute_spec.rb
index 2da178d2c..faea0b483 100644
--- a/spec/lib/model_attribute_spec.rb
+++ b/spec/lib/model_attribute_spec.rb
@@ -31,6 +31,21 @@ RSpec.describe ModelAttribute do
     end
   end
 
+  describe ".methods_by_class_and_type" do
+    it "returns ModelAttributes of a certain class and type" do
+      ModelAttribute.instance_variable_set(:@__all__, [
+        ModelAttribute.new(:route, :name, :string),
+        ModelAttribute.new(:route, :checked_at, :date),
+        ModelAttribute.new(:journey_pattern, :name, :string),
+        ModelAttribute.new(:journey_pattern, :section_status, :integer)
+      ])
+
+      expect(ModelAttribute.methods_by_class_and_type(:route, :string)).to match_array([
+        ModelAttribute.new(:route, :name, :string)
+      ])
+    end
+  end
+
   describe "#code" do
     it "returns a string representation of the attribute" do
       model_attr = ModelAttribute.new(:route, :name, :string)