ChampsService: add tests and refactor

spec/models/champ_shared_example.rb

@@ -14,6 +14,33 @@ shared_examples 'champ_spec' do
     it { is_expected.to delegate_method(:order_place).to(:type_de_champ) }
   end
 
+  describe 'mandatory_and_blank?' do
+    let(:type_de_champ) { TypeDeChamp.new(mandatory: mandatory) }
+    let(:champ) { Champ.new(type_de_champ: type_de_champ, value: value) }
+    let(:value) { '' }
+    let(:mandatory) { true }
+
+    context 'when mandatory and blank' do
+      it { expect(champ.mandatory_and_blank?).to be(true) }
+    end
+
+    context 'when not blank' do
+      let(:value) { 'yop' }
+      it { expect(champ.mandatory_and_blank?).to be(false) }
+    end
+
+    context 'when not mandatory' do
+      let(:mandatory) { false }
+      it { expect(champ.mandatory_and_blank?).to be(false) }
+    end
+
+    context 'when not mandatory or blank' do
+      let(:value) { 'u' }
+      let(:mandatory) { false }
+      it { expect(champ.mandatory_and_blank?).to be(false) }
+    end
+  end
+
   describe 'data_provide' do
     let(:champ) { create :champ }