added assert_queries for the AR test suite

git-svn-id: http://svn-commit.rubyonrails.org/rails/trunk@3784 5ecf4fe2-1ee6-0310-87b1-e25e094e27de

activerecord/test/abstract_unit.rb

@@ -30,7 +30,7 @@ class Test::Unit::TestCase #:nodoc:
     end
   end
 
-  def assert_no_queries
+  def assert_queries(num = 1)
     ActiveRecord::Base.connection.class.class_eval do
       self.query_count = 0
       alias_method :execute, :execute_with_query_counting
@@ -40,7 +40,11 @@ class Test::Unit::TestCase #:nodoc:
     ActiveRecord::Base.connection.class.class_eval do
       alias_method :execute, :execute_without_query_counting
     end
-    assert_equal 0, ActiveRecord::Base.connection.query_count, "1 or more queries were executed"
+    assert_equal num, ActiveRecord::Base.connection.query_count, "#{ActiveRecord::Base.connection.query_count} instead of #{num} queries were executed."
+  end
+
+  def assert_no_queries(&block)
+    assert_queries(0, &block)
   end
 end
 

activerecord/test/base_test.rb

@@ -1147,6 +1147,13 @@ class BasicsTest < Test::Unit::TestCase
     assert_equal LoosePerson, LooseDescendant.base_class
   end
 
+  def test_assert_queries
+    query = lambda { ActiveRecord::Base.connection.execute 'select count(*) from developers' }
+    assert_queries(2) { 2.times { query.call } }
+    assert_queries 1, &query
+    assert_no_queries { assert true }
+  end
+
   # FIXME: this test ought to run, but it needs to run sandboxed so that it
   # doesn't b0rk the current test environment by undefing everything.
   #