diff --git a/test/models/bubble_test.rb b/test/models/bubble_test.rb
index 40cdbe4ad..f5d730769 100644
--- a/test/models/bubble_test.rb
+++ b/test/models/bubble_test.rb
@@ -19,13 +19,81 @@ class BubbleTest < ActiveSupport::TestCase
     end
   end
 
-  test "assigning" do
-    bubbles(:logo).assign users(:david)
+  test "assignment" do
+    assert bubbles(:logo).assigned_to?(users(:kevin))
+    assert_not bubbles(:logo).assigned_to?(users(:david))
+  end
 
-    assert_equal users(:kevin, :jz, :david), bubbles(:logo).assignees
+  test "assigning" do
+    assert_difference %w[ bubbles(:logo).assignees.count Event.count ], +1 do
+      bubbles(:logo).assign users(:david)
+      bubbles(:logo).assign users(:david) # idempotent
+    end
+
+    assert bubbles(:logo).assigned_to?(users(:david))
+    assert_equal "assigned", Event.last.action
     assert_equal [ users(:david) ], Event.last.assignees
   end
 
+  test "unassigning" do
+    assert_difference({ "bubbles(:logo).assignees.count" => -1, "Event.count" => +1 }) do
+      bubbles(:logo).unassign users(:kevin)
+      bubbles(:logo).unassign users(:kevin) # idempotent
+    end
+
+    assert_not bubbles(:logo).assigned_to?(users(:kevin))
+    assert_equal "unassigned", Event.last.action
+    assert_equal [ users(:kevin) ], Event.last.assignees
+  end
+
+  test "toggling assignment" do
+    assert bubbles(:logo).assigned_to?(users(:kevin))
+
+    bubbles(:logo).toggle_assignment users(:kevin)
+    assert_not bubbles(:logo).assigned_to?(users(:kevin))
+
+    bubbles(:logo).toggle_assignment users(:kevin)
+    assert bubbles(:logo).assigned_to?(users(:kevin))
+  end
+
+  test "tag state" do
+    assert bubbles(:logo).tagged_with?(tags(:web))
+    assert_not bubbles(:logo).tagged_with?(tags(:mobile))
+  end
+
+  test "tagging" do
+    assert_difference "bubbles(:logo).taggings.count", +1 do
+      bubbles(:logo).tag tags(:mobile)
+      bubbles(:logo).tag tags(:mobile) # idempotent
+    end
+
+    assert bubbles(:logo).tagged_with?(tags(:mobile))
+
+    assert_difference %w[ bubbles(:logo).taggings.count accounts("37s").tags.count ], +1 do
+      bubbles(:logo).tag Tag.new(title: "prioritized")
+    end
+
+    assert_equal "prioritized", bubbles(:logo).taggings.last.tag.title
+  end
+
+  test "untagging" do
+    assert_difference "bubbles(:logo).taggings.count", -1 do
+      bubbles(:logo).untag tags(:web)
+    end
+
+    assert_not bubbles(:logo).tagged_with?(tags(:web))
+  end
+
+  test "toggling tag" do
+    assert bubbles(:logo).tagged_with?(tags(:web))
+
+    bubbles(:logo).toggle_tag tags(:web)
+    assert_not bubbles(:logo).tagged_with?(tags(:web))
+
+    bubbles(:logo).toggle_tag tags(:web)
+    assert bubbles(:logo).tagged_with?(tags(:web))
+  end
+
   test "searchable by title" do
     bubble = buckets(:writebook).bubbles.create! title: "Insufficient haggis", creator: users(:kevin)