Fix disks_order call

src/lib/bootloader/grub2.rb

@@ -178,7 +178,7 @@ def disk_order_summary
       Yast::Builtins.sformat(
         # part of summary, %1 is a list of hard disks device names
         _("Order of Hard Disks: %1"),
-        device_map.disks_order(", ")
+        device_map.disks_order.join(", ")
       )
     end
 

test/grub2_test.rb

@@ -179,6 +179,35 @@
     it "contains line saying that bootloader type is GRUB2" do
       expect(subject.summary).to include("Boot Loader Type: GRUB2")
     end
+
+    context "when arch is not s390" do
+      before do
+        allow(Yast::Arch).to receive(:s390).and_return(false)
+      end
+
+      it "includes order of hard disks if there are more than 1" do
+        allow(subject.device_map).to receive(:size).and_return(2)
+        allow(subject.device_map).to receive(:disks_order).and_return(["/dev/sda", "/dev/sdb"])
+
+        expect(subject.summary).to include(%r{Order of Hard Disks: /dev/sda, /dev/sdb})
+      end
+
+      it "does not include order of hard disk if there is only 1" do
+        allow(subject.device_map).to receive(:size).and_return(1)
+
+        expect(subject.summary).to_not include(/Order of Hard Disks/)
+      end
+    end
+
+    context "when arch is s390" do
+      before do
+        allow(Yast::Arch).to receive(:s390).and_return(true)
+      end
+
+      it "does not includes order of hard disks" do
+        expect(subject.summary).to_not include(/Order of Hard Disks/)
+      end
+    end
   end
 
   describe "#merge" do