#cast_value properly handles nil

CHANGELOG.md

@@ -2,6 +2,8 @@
 
 ## master
 
+- [PR #10](https://github.com/DmitryTsepelev/store_model/pull/6) Fixes [Issue #9](https://github.com/DmitryTsepelev/store_model/pull/9)
+
 ## 0.3.0 (2019-05-06)
 
 - [PR #6](https://github.com/DmitryTsepelev/store_model/pull/6) Rewrite MergeErrorStrategy to work with Rails 6.1 ([@DmitryTsepelev][])

Gemfile

@@ -3,12 +3,11 @@ git_source(:github) { |repo| "https://github.com/#{repo}.git" }
 
 gemspec
 
-gem "sqlite3", "~> 1.3.6"
-
 local_gemfile = File.join(__dir__, "Gemfile.local")
 
 if File.exist?(local_gemfile)
   eval(File.read(local_gemfile)) # rubocop:disable Security/Eval
 else
+  gem "sqlite3", "~> 1.3.6"
   gem "activerecord", "~> 5.0"
 end

lib/store_model/types/array_type.rb

@@ -17,6 +17,7 @@ def cast_value(value)
         case value
         when String then decode_and_initialize(value)
         when Array then ensure_model_class(value)
+        when nil then value
         else
           raise StoreModel::Types::CastError,
                 "failed casting #{value.inspect}, only String or Array instances are allowed"

lib/store_model/types/json_type.rb

@@ -17,7 +17,7 @@ def cast_value(value)
         case value
         when String then decode_and_initialize(value)
         when Hash then @model_klass.new(value)
-        when @model_klass then value
+        when @model_klass, nil then value
         else
           raise StoreModel::Types::CastError,
                 "failed casting #{value.inspect}, only String, " \

spec/store_model/types/array_type_spec.rb

@@ -35,10 +35,11 @@
   end
 
   describe "#cast_value" do
-    shared_examples "cast examples" do
-      subject { type.cast_value(value) }
+    subject { type.cast_value(value) }
 
+    shared_examples "cast examples" do
       it { is_expected.to be_a(Array) }
+
       it "assigns attributes" do
         subject.zip(attributes_array).each do |config, config_attributes|
           expect(config).to have_attributes(config_attributes)
@@ -61,6 +62,12 @@
       include_examples "cast examples"
     end
 
+    context "when nil is passed" do
+      let(:value) { nil }
+
+      it { is_expected.to be_nil }
+    end
+
     context "when instance of illegal class is passed" do
       let(:value) { {} }
 

spec/store_model/types/json_type_spec.rb

@@ -25,9 +25,9 @@
   end
 
   describe "#cast_value" do
-    shared_examples "cast examples" do
-      subject { type.cast_value(value) }
+    subject { type.cast_value(value) }
 
+    shared_examples "cast examples" do
       it { is_expected.to be_a(Configuration) }
       it("assigns attributes") { is_expected.to have_attributes(attributes) }
     end
@@ -47,6 +47,12 @@
       include_examples "cast examples"
     end
 
+    context "when nil is passed" do
+      let(:value) { nil }
+
+      it { is_expected.to be_nil }
+    end
+
     context "when instance of illegal class is passed" do
       let(:value) { [] }