Merge pull request #195 from dry-rb/refine-accessors

Refine accessors to support invalid method names

Author: flash-gordon

changelog.yml

@@ -5,6 +5,7 @@
   fixed:
   - 'Fixed coercion errors for structs (issue #192 via #193)
     (@flash-gordon)'
+  - "Invalid method names are now allowed as struct attributes (issue #169 via #195) (@flash-gordon)"
   changed:
   - 'Missing attribute error now includes the name of the class (issue #170 via #191)
     (@phillipoertel + @cllns)'

lib/dry/struct/class_interface.rb

@@ -466,18 +466,27 @@ def build_type(name, type = Undefined, &)
       end
       private :build_type
 
+      # @api private
       def define_accessors(keys)
-        keys.each do |key|
-          next if instance_methods.include?(key)
-
-          class_eval(<<-RUBY, __FILE__, __LINE__ + 1)
-            def #{key}                      # def email
-              @attributes[#{key.inspect}]   #   @attributes[:email]
-            end                             # end
-          RUBY
+        (keys - instance_methods).each do |key|
+          if valid_method_name?(key)
+            class_eval(<<-RUBY, __FILE__, __LINE__ + 1)
+              def #{key}                      # def email
+                @attributes[#{key.inspect}]   #   @attributes[:email]
+              end                             # end
+            RUBY
+          else
+            define_method(key) { @attributes[key] }
+          end
         end
       end
       private :define_accessors
+
+      # @api private
+      def valid_method_name?(key)
+        key.to_s.match?(/\A[a-zA-Z_]\w*\z/)
+      end
+      private :valid_method_name?
     end
   end
 end

spec/integration/attributes_from_spec.rb

@@ -84,6 +84,32 @@ class User < Dry::Struct
       expect(Test::User.attribute_names).to eql(%i[address])
     end
 
+    context "when attribute name is not a valid method name" do
+      before do
+        module Test
+          class InvalidName < Dry::Struct
+            attribute :"123", "string"
+            attribute :":", "string"
+            attribute :"with space", "string"
+            attribute :"with-dash", "string"
+          end
+        end
+      end
+
+      it "adds an accessor" do
+        odd_struct = Test::InvalidName.new(
+          "123": "John",
+          ":": "Jane",
+          "with space": "Doe",
+          "with-dash": "Smith"
+        )
+        expect(odd_struct.public_send(:"123")).to eql("John")
+        expect(odd_struct.public_send(:":")).to eql("Jane")
+        expect(odd_struct.public_send("with space")).to eql("Doe")
+        expect(odd_struct.public_send("with-dash")).to eql("Smith")
+      end
+    end
+
     context "inheritance" do
       before do
         class Test::Person < Dry::Struct