fix: bug coercing boolean strings (#126)

- fields with a type of T::Boolean were getting caught in the T.any conditional block and failing to activate the BooleanCoercer class. I moved the `select_coercer_by` call up to the serializer so we can handle the case where the type alias matches a coercer, falling back to checking each of the individual types in the alias if no top-level coercer is found.

lib/typed/serializer.rb

@@ -34,11 +34,19 @@ def serialize(struct)
     def deserialize_from_creation_params(creation_params)
       results = schema.fields.map do |field|
         value = creation_params.fetch(field.name, nil)
+        coercer = Coercion::CoercerRegistry.instance.select_coercer_by(type: field.type)
 
         if value.nil? && !field.default.nil?
           Success.new(Validations::ValidatedValue.new(name: field.name, value: field.default))
         elsif value.nil? || field.works_with?(value)
           field.validate(value)
+        elsif !coercer.nil?
+          result = coercer.new.coerce(type: field.type, value:)
+          if result.success?
+            field.validate(result.payload)
+          else
+            Failure.new(Validations::ValidationError.new(result.error.message))
+          end
         elsif field.type.class <= T::Types::Union
           errors = []
           validated_value = T.let(nil, T.nilable(Typed::Result[Typed::Validations::ValidatedValue, Typed::Validations::ValidationError]))
@@ -60,13 +68,7 @@ def deserialize_from_creation_params(creation_params)
 
           validated_value.nil? ? Failure.new(Validations::ValidationError.new(errors.map(&:message).join(", "))) : validated_value
         else
-          coercion_result = Coercion.coerce(type: field.type, value:)
-
-          if coercion_result.success?
-            field.validate(coercion_result.payload)
-          else
-            Failure.new(Validations::ValidationError.new(coercion_result.error.message))
-          end
+          Failure.new(Validations::ValidationError.new("Coercer not found for type #{field.type}."))
         end
       end
 

test/typed/hash_serializer_test.rb

@@ -109,6 +109,20 @@ def test_with_boolean_it_can_deserialize
     assert_payload(NEW_YORK_CITY, result)
   end
 
+  def test_with_boolean_string_false_it_can_deserialize
+    result = Typed::HashSerializer.new(schema: Typed::Schema.from_struct(City)).deserialize({name: "New York", capital: "false"})
+
+    assert_success(result)
+    assert_payload(NEW_YORK_CITY, result)
+  end
+
+  def test_with_boolean_string_true_it_can_deserialize
+    result = Typed::HashSerializer.new(schema: Typed::Schema.from_struct(City)).deserialize({name: "DC", capital: "true"})
+
+    assert_success(result)
+    assert_payload(DC_CITY, result)
+  end
+
   def test_with_array_it_can_deserialize
     result = Typed::HashSerializer.new(schema: Typed::Schema.from_struct(Country)).deserialize({name: "US", cities: [NEW_YORK_CITY, DC_CITY], national_items: {bird: "bald eagle", anthem: "The Star-Spangled Banner"}})
 

test/typed/json_serializer_test.rb

@@ -60,6 +60,20 @@ def test_with_boolean_it_can_deserialize
     assert_payload(NEW_YORK_CITY, result)
   end
 
+  def test_with_boolean_string_false_it_can_deserialize
+    result = Typed::JSONSerializer.new(schema: Typed::Schema.from_struct(City)).deserialize('{"name":"New York","capital":"false"}')
+
+    assert_success(result)
+    assert_payload(NEW_YORK_CITY, result)
+  end
+
+  def test_with_boolean_string_true_it_can_deserialize
+    result = Typed::JSONSerializer.new(schema: Typed::Schema.from_struct(City)).deserialize('{"name":"DC","capital":"true"}')
+
+    assert_success(result)
+    assert_payload(DC_CITY, result)
+  end
+
   def test_with_array_it_can_deep_deserialize
     result = Typed::JSONSerializer.new(schema: Typed::Schema.from_struct(Country)).deserialize('{"name":"US","cities":[{"name":"New York","capital":false},{"name":"DC","capital":true}],"national_items":{"bird":"bald eagle","anthem":"The Star-Spangled Banner"}}')