Adopt the changes suggested by @jzigmund

app/helpers/application_helper/button/refresh_workers.rb

@@ -1,23 +1,7 @@
 class ApplicationHelper::Button::RefreshWorkers < ApplicationHelper::Button::Basic
-  needs :@record, :@lastaction, :@sb, :@layout
+  needs :@record, :@sb
 
   def visible?
-    return false if miq? && !(ops? && diagnostics_worker_tab?)
-    return !%w(download_logs evm_logs audit_logs).include?(@lastaction) if @record.class == NilClass
-    true
-  end
-
-  private
-
-  def diagnostics_worker_tab?
     @view_context.x_active_tree == :diagnostics_tree && @sb[:active_tab] == 'diagnostics_workers'
   end
-
-  def miq?
-    @record.class == MiqServer || @record.class == MiqRegion
-  end
-
-  def ops?
-    @layout == 'ops'
-  end
 end

spec/helpers/application_helper/buttons/refresh_workers_spec.rb

@@ -1,47 +1,29 @@
 describe ApplicationHelper::Button::RefreshWorkers do
-  before :all do
-    @records = [FactoryGirl.create(:miq_server), FactoryGirl.create(:miq_region)]
-  end
+  let(:view_context) { setup_view_context_with_sandbox({}) }
+  let(:record) { FactoryGirl.create(:miq_server) }
 
   describe '#visible?' do
-    context 'when layout == ops and active_tab == diagnostics_workers in :diagnostics_tree' do
-      it 'will not be skipped' do
-        view_context = setup_view_context_with_sandbox({})
-        button = described_class.new(view_context, {}, {'record' => nil, 'layout' => 'ops'}, {})
-        button.instance_variable_set(:@sb, :active_tab => 'diagnostics_workers')
+    context 'when x_active_tree == diagnostics_tree and active_tab != diagnostics_workers' do
+      it 'will be skipped' do
+        button = described_class.new(view_context, {}, {'record' => record}, {})
+        button.instance_variable_set(:@sb, :active_tab => 'does not matter')
         allow(view_context).to receive(:x_active_tree).and_return(:diagnostics_tree)
-        expect(button.visible?).to be_truthy
-      end
-    end
-
-    context 'when layout != ops and' do
-      %w(miq_server miq_region).each_with_index do |record, i|
-        context "record is #{record}" do
-          it 'will be skipped' do
-            view_context = setup_view_context_with_sandbox({})
-            button = described_class.new(view_context, {}, {'record' => @records[i], 'layout' => 'not ops'}, {})
-            button.instance_variable_set(:@sb, :active_tab => 'does not matter')
-            allow(view_context).to receive(:x_active_tree).and_return(:diagnostics_tree)
-            expect(button.visible?).to be_falsey
-          end
-        end
+        expect(button.visible?).to be_falsey
       end
     end
-
-    %w(download_logs evm_logs audit_logs).each do |lastaction|
-      context "when action #{lastaction} being taken as last" do
-        it 'will be skipped for this record' do
-          view_context = setup_view_context_with_sandbox({})
-          button = described_class.new(view_context, {}, {'record' => nil, 'lastaction' => lastaction}, {})
-          expect(button.visible?).to be_falsey
-        end
+    context 'when x_active_tree != diagnostics_tree and active_tab == diagnostics_workers' do
+      it 'will be skipped' do
+        button = described_class.new(view_context, {}, {'record' => record}, {})
+        button.instance_variable_set(:@sb, :active_tab => 'diagnostics_workers')
+        allow(view_context).to receive(:x_active_tree).and_return(:does_not_matter)
+        expect(button.visible?).to be_falsey
       end
     end
-
-    context 'when other action being taken as last' do
-      it 'will not be skipped for this record' do
-        view_context = setup_view_context_with_sandbox({})
-        button = described_class.new(view_context, {}, {'record' => nil, 'lastaction' => 'worker_logs'}, {})
+    context 'when x_active_tree == diagnostics_tree and active_tab == diagnostics_workers' do
+      it 'will not be skipped' do
+        button = described_class.new(view_context, {}, {'record' => record}, {})
+        button.instance_variable_set(:@sb, :active_tab => 'diagnostics_workers')
+        allow(view_context).to receive(:x_active_tree).and_return(:diagnostics_tree)
         expect(button.visible?).to be_truthy
       end
     end