Keep full model name when parsing expression with tag

lib/miq_expression/tag.rb

@@ -1,6 +1,6 @@
 class MiqExpression::Tag < MiqExpression::Target
   REGEX = /
-(?<model_name>([[:alnum:]]*(::)?)?)
+(?<model_name>([[:alnum:]]*(::)?){4})
 \.?(?<associations>([a-z_]+\.)*)
 (?<namespace>\bmanaged|user_tag\b)
 -(?<column>[a-z]+[_[:alnum:]]+)

spec/lib/miq_expression/tag_spec.rb

@@ -21,6 +21,13 @@
                                                             :namespace    => "/managed/service_level")
     end
 
+    it "with model-parent::model.managed-in_tag" do
+      tag = "ManageIQ::Providers::CloudManager.managed-service_level"
+      expect(described_class.parse(tag)).to have_attributes(:model        => ManageIQ::Providers::CloudManager,
+                                                            :associations => [],
+                                                            :namespace    => "/managed/service_level")
+    end
+
     it "with model.associations.associations.managed-in_tag" do
       tag = "Vm.service.user.managed-service_level"
       expect(described_class.parse(tag)).to have_attributes(:model        => Vm,
@@ -63,6 +70,11 @@
       tag = "Vm.managed"
       expect(described_class.parse(tag)).to be_nil
     end
+
+    it "returns nil with invalid case parent-model::model::somethingmanaged-se" do
+      tag = "ManageIQ::Providers::CloudManagermanaged-se'"
+      expect(described_class.parse(tag)).to be_nil
+    end
   end
 
   describe "#to_s" do