- ruby utility for in source unit testing


Quicktest - A utility for inlining ruby unit tests with the ruby code under test


run with bin/quickspec

              class Foo
                def initialize
                  @bar = true
                def quicktest
                  it "bar should be initialized to true" do
                    @bar.should == true
                def self.hello arg
                  "hello" + arg
                def self.quicktest meth
                  it "should prepend 'hello' to its argument" do
                    meth["world"].should == 'hello world' # error - no space 'helloworld'

Running quicktest on the source of this README file outputs the following:

              'Foo hello should prepend 'hello' to its argument' FAILED
              expected: "hello world",
                   got: "helloworld" (using ==)
              ./README:22:in `quicktest'
              /home/greg/quicktest/lib/quicktest.rb:65:in `instance_eval'
              /home/greg/quicktest/lib/quicktest.rb:65:in `run_tests'
              Finished in 0.008338 seconds
              2 examples, 1 failure



              gem install quicktest

test code

To test a method, place another method called ‘quicktest’ immediately after it the quicktest method has one OPTIONAL argument:

  • a method object for the method under test


run with

              spec -r quicktest file_to_test

There is a convenience script so that you can just run

              quickspec file_to_test

Author and License

Copyright (c) 2008 Greg Weber, gregweber.info Licensed under the MIT license


The typical test driven development workflow requires constant switching between the file containg the source code and the the file containg the tests. When creating code, it is much faster to be able to place tests immediately after the code you are writing. After the code has been written, it may be a good idea to move it to another file.

Quicktest is designed to support quick tests in a framework agnostic way. Currently, only an rspec testrunner is available, but it is trivial to write one for another testing framework.

Quicktest uses method tracing to know the method you are testing. By default the output of a failed test will show the object and method name.


gem install quicktest





git clone git://github.com/gregwebs/quicktest.git



RDoc documentation

included with the gem

Important Notes

  • def quicktest will instantiate an object for the class you are testing, which gives a convenient referenct to self in the quicktest method. However, it calls new() without any parameters. If you need parameters for new(), you will have to use def self.quicktest and call new() yourself


  • when testing module instance methods, the module is included into an anonymous class. By default, that class inherits from Object. To change this you must define an object that the module will be included into by defining the following in the module:

    def self.quicktest_include_into; String end

  • you can change the testing method name from quicktest to something else using the command line option

    —quicktest better_testing_name


  • quicktest methods not working properly? if the class (or one of its ancestors) is overriding method tracing then including QuickTest::Tracer will fix it, but you should also fix the class or its ancestor.

Unimportant Notes

production performance

leaving test code in with your production code is not necessarily a good idea, but you can put

              remove_method :quicktest

at the bottom of a class to completely remove the quicktest method


  • tests for scripts

Definitely very useful for one file scripts, or any type of code that does not have a well established project home where the tests will be. You can distribute the tests with script so that anyone who wants to modify it can also modify the tests instead of assuming the original author did not write any. You can have a flow of development where a ‘quick and dirty’ script becomes well tested. Here is a shell function that tests the file before every run.

              function test_run () { quickspec $1 && $1 }
  • documentation

Tests are a form of documentation. It can be argued that it is better to have all documentation include in the source

  • efficient TDD and prototyping

When writing fresh code you now have the possibility to be directly next to the code under test without having to switch back and forth between files. When you are done writing the new code, you can easily pull all the quicktest methods out and into a spec file.


Quicktest came out of my dabbling in the D programming language, which allows you to place testing blocks inline with your source code


Normally, these blocks are ignored, but if you compile with a different switch, they are linked in and ran at the beginning of your program. Originally, I made an exact copy of this, but among other things, it requires the placement of a line like

              (def unittest;end) if not defined? unittest

at the beginning of the file. It would be nice if Ruby had a similar construct built in to the language.


Quicktest uses method tracing to know the method you are testing. For the object under test, testing methods are included into it, and then the test is run.