= Ruby Q.E.D. homepage: http://proutils.github.com/qed mailing list: http://groups.google.com/group/proutils development: http://github.com/proutils/qed == Introduction Q.E.D. is an abbreviation for the well known Latin phrase "Quod Erat Demonstrandum", literally "which was to be demonstrated", which is oft written in its abbreviated form at the end of a mathematical proof or philosophical argument to signify the a successful conclusion. And so it is too for Ruby Q.E.D., though it might as easily be taken to stand for "Quality Ensured Documentation". QED is in fact both a test framework and a documentation system for Ruby developers. QED sits somewhere between lower-level testing tools like Test::Unit and grand requirement specifications tools like Cucumber. In practice it works exceptionally well for API-Driven Design, which is especially useful when designing reusable libraries, but it can be used to test code at any level of abstract, from unit test to systems tests. == Features * Write tests and documentation in the same breath! * Demos can be RDoc, Markdown or any other conforming text format. * Uses the excellent Assertive Expressive library for assertions. * Table macro allows large sets of data to be run by the same code. * Documentation tool provides nice output with jQuery-based TOC. == Synopsis === Assertion Syntax QED uses the AE (Assertive Expressive) library to provide an elegant means to make assertions. To give a quick overview, assertion can be written as: 4.assert == 5 In this example, because 4 != 5, this expression will raise an Assertion exception. QED's Runner class is thus just a means of running and capturing code blocks containing these assertions. You can learn more about AE at http://proutils.github.com/ae. === Document Structure QED documents are simply text files called *demonstrandum*. Because they largely consist of free-form descriptive text, they are a practice pure Literate Programming. For example: = Example Shows that the number 5 does not equal 4. 5.assert! == 4 But in fact equals 5. 5.assert == 5 In this example RDoc was chosen for the document format. However, almost any text format can be used. The only necessary distinction is that description text align to the left margin and all code be indented, although QED does recognize RDoc and Markdown single-line style headers, so any format that supports those (which covers many markup formats in use today) will have mildly improved console output. In any case, the essential take away here is that QED *demonstrandum* are simply descriptive documents with interspersed blocks of example code. Give this design some thought. It should become clear that this approach is especially fruitful in that it allows *documentation* and *specification* to seamlessly merge into a unified *demonstration*. === Running Demonstrations If we were to run the above document through QED in verbatim mode the output would be identical (assuming we did not make a typo and the assertions passed). If there were errors or failures, we would see information detailing each. To run a document through QED, simply use the +qed+ command. $ qed -v demo/01_example.rdoc The -v option specifies verbatim mode, which outputs the entire document. Notice we placed the QED document in the demo/ or demos/ directory, this is the conical place that has been designated for them, though you can of course put them elsewhere in your project if you prefer. Also notice the 01_ prefix in front of the name. While this is not strictly necessary, it helps order the documents properly when generating QED documentation (QEDocs). === Utilizeing Applique QED demonstrandum descriptive text is not stricty passive explination. Using pattern matching techniques, document phrases can trigger underlying actions. These actions provide a support structure for running tests called the *applique*. Creating an applique is easy. Along with your QED scripts, to which the applique will apply, create an applique/ directory. In this directory add Ruby scripts. When you run your demos every Ruby script in the directory will be automatically loaded. Within these applique scripts *advice* can be defined. Advice can be either *event advice*, which is simply triggered by some fixed cycle of running, such as Before :each or After :all, and *pattern advice* which are used to match against descriptive phrases in the QED demos. An example would be: When "a new round is started" do @round = [] end So that whenever the phrase "a new round is started" appears in a demo, the @round instance variable with be reset to an empty array. It is rather amazing what can be accomplished with such a system, be sure to look at QED's own demonstrandum to get a better notion of how you can put the the system to use. === Generating Documentation To generate documentation from QED documents, use the +qedoc+ command. $ qedoc --output doc/qedoc --title "Example" demo/*.rdoc When documenting, QED recognizes the format by the file extension and treats it accordingly. An extension of .qed is treated the same as .rdoc. Use the --help options on each command to get more information on the use of these commands. == Requirements QED depends on the following external libraries: * AE - Assertions Framework * ANSI - ANSI Color Codes * Facets - Core Extensions These will be automatically installed when installing QED via RubyGems, if they are not already installed. == Copyright and License Q.E.D. Copyright (c) 2007 Thomas Sawyer Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at http://www.apache.org/licenses/LICENSE-2.0 Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.