Merged r23431 from trunk to 6.0-stable (#42066).

git-svn-id: https://svn.redmine.org/redmine/branches/6.0-stable@23435 e93f8b46-1217-0410-a6f0-8f06a7374b81

2 files changed, 22 insertions, 2 deletions

diff --git a/app/models/issue_priority.rb b/app/models/issue_priority.rb
index d60098c06..1bad524dc 100644
--- a/app/models/issue_priority.rb
+++ b/app/models/issue_priority.rb
@@ -60,11 +60,15 @@ class IssuePriority < Enumeration
   end
 
   def high?
-    position > self.class.default_or_middle.position
+    return false unless (baseline_position = self.class.default_or_middle&.position)
+
+    position > baseline_position
   end
 
   def low?
-    position < self.class.default_or_middle.position
+    return false unless (baseline_position = self.class.default_or_middle&.position)
+
+    position < baseline_position
   end
 
   # Updates position_name for active priorities
diff --git a/test/unit/issue_priority_test.rb b/test/unit/issue_priority_test.rb
index e076afe67..80dc11e1c 100644
--- a/test/unit/issue_priority_test.rb
+++ b/test/unit/issue_priority_test.rb
@@ -156,4 +156,20 @@ class IssuePriorityTest < ActiveSupport::TestCase
     IssuePriority.find_by_position_name('highest').destroy
     assert_equal %w(lowest default high2 highest), IssuePriority.active.to_a.sort.map(&:position_name)
   end
+
+  def test_high_should_return_false_when_no_default_priority_and_no_active_priorities
+    IssuePriority.update_all(active: false, is_default: false)
+    priority = IssuePriority.order(:position).last # Highest priority
+    assert_nothing_raised do
+      assert_equal false, priority.high?
+    end
+  end
+
+  def test_low_should_return_false_when_no_default_priority_and_no_active_priorities
+    IssuePriority.update_all(active: false, is_default: false)
+    priority = IssuePriority.order(:position).first # Lowest priority
+    assert_nothing_raised do
+      assert_equal false, priority.low?
+    end
+  end
 end