do not delete report when linked MiqTask deleted

BZ: https://bugzilla.redhat.com/show_bug.cgi?id=1450272
Changes:
- removed :dependent => :destroy on miq_report_result association in MiqTask
- refactor MiqReportResult#status to return 'Complete' if task asociated with report deleted
- added test coverage for MiqReportResult#status
- remove not used virtual_delegate to MiqTask#state_or_status

app/models/miq_report_result.rb

@@ -11,10 +11,8 @@ class MiqReportResult < ApplicationRecord
   serialize :report
 
   virtual_delegate :description, :to => :miq_group, :prefix => true, :allow_nil => true
-  virtual_delegate :state_or_status, :to => "miq_task", :allow_nil => true
-  virtual_attribute :status, :string, :uses => :state_or_status
+  virtual_attribute :status, :string
   virtual_column :status_message,        :type => :string, :uses => :miq_task
-
   virtual_has_one :result_set,           :class_name => "Hash"
 
   before_save do
@@ -32,11 +30,15 @@ def result_set
   end
 
   def status
-    MiqTask.human_status(state_or_status)
+    if miq_task
+      miq_task.human_status
+    else
+      report_results.blank? ? "Error" : "Complete"
+    end
   end
 
   def status_message
-    miq_task.nil? ? _("Report results are no longer available") : miq_task.message
+    miq_task.nil? ? _("The task associated with this report is no longer available") : miq_task.message
   end
 
   def report_results

app/models/miq_task.rb

@@ -19,7 +19,7 @@ class MiqTask < ApplicationRecord
 
   has_one :log_file, :dependent => :destroy
   has_one :binary_blob, :as => :resource, :dependent => :destroy
-  has_one :miq_report_result, :dependent => :destroy
+  has_one :miq_report_result
   has_one :job, :dependent => :destroy
 
   belongs_to :miq_server

spec/models/miq_report_result_spec.rb

@@ -125,6 +125,35 @@
     end
   end
 
+  describe "#status" do
+    let(:report_name) { "Vendor and Guest OS" }
+    let(:task) { FactoryGirl.create(:miq_task) }
+    let(:miq_report_result) do
+      MiqReport.seed_report(report_name)
+      report = MiqReport.where(:name => report_name).last
+      report.generate_table(:userid => "test")
+      task.miq_report_result = report.build_create_results({:userid => "test"}, task.id)
+      MiqReportResult.find_by(:miq_task_id => task.id)
+    end
+
+    it "returns 'Running' if associated task exists and report not ready" do
+      expect(miq_report_result.status).to eq "Running"
+    end
+
+    it "returns 'Complete' if report generated and associated task exists" do
+      task.update_status("Finished", "Ok", "Generate Report result")
+      expect(miq_report_result.status).to eq "Complete"
+    end
+
+    it "returns 'Complete' if task ssociated with report deleted" do
+      expect(miq_report_result.status).to eq "Running"
+      task.update_status("Finished", "Ok", "Generate Report result")
+      task.destroy
+      miq_report_result.reload
+      expect(miq_report_result.status).to eq "Complete"
+    end
+  end
+
   describe "serializing and deserializing report results" do
     it "can serialize and deserialize an MiqReport" do
       report = FactoryGirl.build(:miq_report)