move counter_cache tests to a separate file and refactor

activerecord/test/cases/base_test.rb

@@ -708,55 +708,6 @@ def test_boolean_attributes
     assert Topic.find(2).approved?
   end
 
-  def test_increment_counter
-    Topic.increment_counter("replies_count", 1)
-    assert_equal 2, Topic.find(1).replies_count
-
-    Topic.increment_counter("replies_count", 1)
-    assert_equal 3, Topic.find(1).replies_count
-  end
-
-  def test_decrement_counter
-    Topic.decrement_counter("replies_count", 2)
-    assert_equal(-1, Topic.find(2).replies_count)
-
-    Topic.decrement_counter("replies_count", 2)
-    assert_equal(-2, Topic.find(2).replies_count)
-  end
-
-  def test_reset_counters
-    assert_equal 1, Topic.find(1).replies_count
-
-    Topic.increment_counter("replies_count", 1)
-    assert_equal 2, Topic.find(1).replies_count
-
-    Topic.reset_counters(1, :replies)
-    assert_equal 1, Topic.find(1).replies_count
-  end
-
-  def test_update_counter
-    category = categories(:general)
-    assert_nil category.categorizations_count
-    assert_equal 2, category.categorizations.count
-
-    Category.update_counters(category.id, "categorizations_count" => category.categorizations.count)
-    category.reload
-    assert_not_nil category.categorizations_count
-    assert_equal 2, category.categorizations_count
-
-    Category.update_counters(category.id, "categorizations_count" => category.categorizations.count)
-    category.reload
-    assert_not_nil category.categorizations_count
-    assert_equal 4, category.categorizations_count
-
-    category_2 = categories(:technology)
-    count_1, count_2 = (category.categorizations_count || 0), (category_2.categorizations_count || 0)
-    Category.update_counters([category.id, category_2.id], "categorizations_count" => 2)
-    category.reload; category_2.reload
-    assert_equal count_1 + 2, category.categorizations_count
-    assert_equal count_2 + 2, category_2.categorizations_count
-  end
-
   def test_update_all
     assert_equal Topic.count, Topic.update_all("content = 'bulk updated!'")
     assert_equal "bulk updated!", Topic.find(1).content

activerecord/test/cases/counter_cache_test.rb

+require 'cases/helper'
+require 'models/topic'
+require 'models/reply'
+require 'models/category'
+require 'models/categorization'
+
+class CounterCacheTest < ActiveRecord::TestCase
+  fixtures :topics, :categories, :categorizations
+
+  setup do
+    @topic = Topic.find(1)
+  end
+
+  test "increment counter" do
+    assert_difference '@topic.reload.replies_count' do
+      Topic.increment_counter(:replies_count, @topic.id)
+    end
+  end
+
+  test "decrement counter" do
+    assert_difference '@topic.reload.replies_count', -1 do
+      Topic.decrement_counter(:replies_count, @topic.id)
+    end
+  end
+
+  test "reset counters" do
+    # throw the count off by 1
+    Topic.increment_counter(:replies_count, @topic.id)
+
+    # check that it gets reset
+    assert_difference '@topic.reload.replies_count', -1 do
+      Topic.reset_counters(@topic.id, :replies)
+    end
+  end
+
+  test "update counter with initial null value" do
+    category = categories(:general)
+    assert_equal 2, category.categorizations.count
+    assert_nil category.categorizations_count
+
+    Category.update_counters(category.id, :categorizations_count => category.categorizations.count)
+    assert_equal 2, category.reload.categorizations_count
+  end
+
+  test "update counter for decrement" do
+    assert_difference '@topic.reload.replies_count', -3 do
+      Topic.update_counters(@topic.id, :replies_count => -3)
+    end
+  end
+
+  test "update counters of multiple records" do
+    t1, t2 = topics(:first, :second)
+
+    assert_difference ['t1.reload.replies_count', 't2.reload.replies_count'], 2 do
+      Topic.update_counters([t1.id, t2.id], :replies_count => 2)
+    end
+  end
+end