Cutest

Forking tests.

Description

Run tests in separate processes to avoid shared state.

Each test file is run in a forked process and, if the second parameter to Cutest.run is true, it is also loaded inside an anonymous module. Once a failure is found in a file, the rest of the file is skipped and the error is reported. This way, running your test suite feels faster.

You can use the scope command around tests: it guarantees that no instance variables are shared between tests.

There are two commands very similar in nature, but with a subtle difference that makes them easy to combine in order to satisfy different needs: prepare and setup.

The prepare blocks are executed before each test. If you call prepare many times, each passed block is appended to an array. When the test is run, all those prepare blocks are executed in order. The result of the block is discarded, so it is only useful for preparing the environment (flushing the database, removing a directory, etc.).

The setup block is executed before each test and the result is passed as a parameter to the test block. Unlike prepare, each definition of setup overrides the previous one. Even if you can declare instance variables and share them between tests, the recommended usage is to pass the result of the block as a parameter to the test blocks.

The test method executes the passed block after running prepare and setup. This is where assertions must be declared.

Two assertions are available: assert and assert_raise. The first accepts a value and raises an AssertionFailed exception if it's false or nil, and the later receives an expected exception and a block: the block is executed and the raised exception is compared with the expected one. An AssertionFailed exception is raised if the block runs fine or if the raised exception doesn't match the expectation.

Usage

In your Rakefile:

require "cutest"

task :test do
  Cutest.run(Dir["test/*"])
end

task :default => :test

In your tests:

setup do
  {:a => 23, :b => 43}
end

test "should receive the result of the setup block as a parameter" do |params|
  assert params == {:a => 23, :b => 43}
end

test "should evaluate the setup block before each test" do |params|
  params[:a] = nil
end

test "should preserve the original values from the setup" do |params|
  assert 23 == params[:a]
end

To run the tests:

$ rake

A binary is shipped with Cutest, so you can alternatively run:

$ cutest test/*.rb

If you get an error, the report will look like this:

>> should preserve the original values from the setup
=> assert 24 == params[:a]
   test/a_test.rb +14

Instead of a description of the error, you get to see the assertion that failed along with the file and line number. Adding a debugger and fixing the bug is left as an exercise for the reader.

An example working with a prepare block:

prepare do
  Ohm.flush
end

setup do
  Ohm.redis.get("foo")
end

test do |foo|
  assert foo.nil?
end

And working with scopes:

setup do
  @foo = true
end

@bar = true

scope do
  test "should not share instance variables" do |foo|
    assert !defined?(@foo)
    assert !defined?(@bar)
    assert foo == true
  end
end

The tests in these two examples will pass.

Unlike other testing frameworks, Cutest does not compile all the tests before running them. Another shift in design is that one dot is shown after a file is examined, and not the usual one-dot-per-assertion. And finally, the execution of a file stops when the first failure is found.

Installation

$ gem install cutest

License

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

cyx/cutest

Cutest

Description

Usage

Installation

License