Deprecated.
Macro that creates a test asserting a change between the return value of a
block that is run before and after the current setup block is run. This is
similar to Active Support's assert_difference
assertion, but
supports more than just numeric values. See also should_not_change.
The passed description will be used when generating the test name and failure messages.
Example:
context "Creating a post" do setup { Post.create } should_change("the number of posts", :by => 1) { Post.count } end
As shown in this example, the :by
option expects a numeric
difference between the before and after values of the expression. You may
also specify :from
and :to
options:
should_change("the number of posts", :from => 0, :to => 1) { Post.count } should_change("the post title", :from => "old", :to => "new") { @post.title }
Combinations of :by
, :from
, and :to
are allowed:
# Assert the value changed in some way: should_change("the post title") { @post.title } # Assert the value changed to anything other than "old:" should_change("the post title", :from => "old") { @post.title } # Assert the value changed to "new:" should_change("the post title", :to => "new") { @post.title }
This macro was deprecated because these tests aren't as valuable as alternative tests that explicitly test the final state.
Consider an alternative:
context "updating a post" do setup do @post = Post.create(:title => "old") put :update, :post => {:title => "new"}, :id => @post.to_param end should "update the title" do assert_equal "new", @post.reload.title end end
# File lib/shoulda/macros.rb, line 54 def should_change(description, options = {}, &block) ::ActiveSupport::Deprecation.warn("Not considered a useful test. Instead, test the end state explicitly.") by, from, to = get_options!([options], :by, :from, :to) stmt = "change #{description}" stmt << " from #{from.inspect}" if from stmt << " to #{to.inspect}" if to stmt << " by #{by.inspect}" if by before = lambda { @_before_should_change = block.bind(self).call } should stmt, :before => before do old_value = @_before_should_change new_value = block.bind(self).call assert_operator from, :===, old_value, "#{description} did not originally match #{from.inspect}" if from assert_not_equal old_value, new_value, "#{description} did not change" unless by == 0 assert_operator to, :===, new_value, "#{description} was not changed to match #{to.inspect}" if to assert_equal old_value + by, new_value if by end end
Deprecated.
Macro that creates a test asserting that a record of the given class was created.
Example:
context "creating a post" do setup { Post.create(post_attributes) } should_create :post end
# File lib/shoulda/macros.rb, line 122 def should_create(class_name) ::ActiveSupport::Deprecation.warn should_change_record_count_of(class_name, 1, 'create') end
Deprecated.
Macro that creates a test asserting that a record of the given class was destroyed.
Example:
context "destroying a post" do setup { Post.first.destroy } should_destroy :post end
# File lib/shoulda/macros.rb, line 138 def should_destroy(class_name) ::ActiveSupport::Deprecation.warn should_change_record_count_of(class_name, -1, 'destroy') end
Deprecated.
Macro that creates a test asserting no change between the return value of a block that is run before and after the current setup block is run. This is the logical opposite of should_change.
The passed description will be used when generating the test name and failure message.
Example:
context "Updating a post" do setup { @post.update_attributes(:title => "new") } should_not_change("the number of posts") { Post.count } end
This macro was deprecated because these tests aren't as valuable as alternative tests that explicitly test the final state.
Consider an alternative:
context "updating a post" do setup do @post = Post.create(:title => "old") put :update, :post => {:title => ""}, :id => @post.to_param end should "not update the title" do assert_equal "old", @post.reload.title end end
# File lib/shoulda/macros.rb, line 102 def should_not_change(description, &block) ::ActiveSupport::Deprecation.warn("Not considered a useful test. Instead, test the end state explicitly.") before = lambda { @_before_should_not_change = block.bind(self).call } should "not change #{description}", :before => before do new_value = block.bind(self).call assert_equal @_before_should_not_change, new_value, "#{description} changed" end end