
Source code, additional information, screenshots... available at 
    http://eigenclass.org/hiki/rcov

If you're on win32, you can also find a pre-built rcovrt.so (which makes
code coverage analysis >100 times faster) in the above-mentioned pages.

Overview
========
rcov is a code coverage tool for Ruby. It is commonly used for viewing overall
test coverage of target code. It features:
* fast execution: 20-300 times faster than previous tools
* multiple analysis modes: standard, bogo-profile, "intentional testing",
  dependency analysis...
* detection of uncovered code introduced since the last run ("differential
  code coverage")
* fairly accurate coverage information through code linkage inference using 
  simple heuristics
* cross-referenced XHTML and several kinds of text reports
* support for easy automation with Rake and Rant
* colorblind-friendliness

How do I use it?
================

In the common scenario, your tests are under test/ and the target code
(whose coverage you want) is in lib/. In that case, all you have to do is
use rcov to run the tests (instead of testrb), and a number of XHTML files
with the code coverage information will be generated, e.g.

    rcov -Ilib test/*.rb

will execute all the .rb files under test/ and generate the code coverage
report for the target code (i.e. for the files in lib/) under coverage/. The
target code needs not be under lib/; rcov will detect is as long as it is
require()d by the tests. rcov is smart enough to ignore "uninteresting"
files: the tests themselves, files installed in Ruby's standard locations,
etc.  See  rcov --help  for the list of regexps rcov matches filenames
against.

rcov can also be used from Rake; see README.rake or the RDoc documentation
for more information.

rcov can output information in several formats, and perform different kinds
of analyses in addition to plain code coverage.  See  rcov --help  for a
description of the available options.

Sample output
=============

See http://eigenclass.org/hiki.rb?rcov (once again) for screenshots.

The text report (also used by default in RcovTasks) resembles


+-----------------------------------------------------+-------+-------+--------+
|                  File                               | Lines |  LOC  |  COV   |
+-----------------------------------------------------+-------+-------+--------+
|lib/rcov.rb                                          |   572 |   358 |  91.3% |
+-----------------------------------------------------+-------+-------+--------+
|Total                                                |   572 |   358 |  91.3% |
+-----------------------------------------------------+-------+-------+--------+
91.3%   1 file(s)   572 Lines   358 LOC



The (undecorated) textual output with execution count information looks like this:

 $ rcov --no-html --text-counts b.rb 
 ================================================================================
 ./b.rb
 ================================================================================
                                                                       |      2
 a, b, c = (1..3).to_a                                                 |      2
 10.times do                                                           |      1
   a += 1                                                              |     10
   20.times do |i|                                                     |     10
     b += i                                                            |    200
     b.times do                                                        |    200
       c += (j = (b-a).abs) > 0 ? j : 0                                | 738800
     end                                                               |      0
   end                                                                 |      0
 end                                                                   |      0


rcov can detect when you've added code that was not covered by your unit
tests:

    $ rcov --text-coverage-diff --no-color test/*.rb
    Started
    .......................................
    Finished in 1.163085 seconds.
    
    39 tests, 415 assertions, 0 failures, 0 errors
    
    ================================================================================
    !!!!! Uncovered code introduced in lib/rcov.rb
    
    ### lib/rcov.rb:207
       
	 def precompute_coverage(comments_run_by_default = true)
	   changed = false
	   lastidx = lines.size - 1
	   if (!is_code?(lastidx) || /^__END__$/ =~ @lines[-1]) && !@coverage[lastidx]
    !!       # mark the last block of comments
    !!       @coverage[lastidx] ||= :inferred
    !!       (lastidx-1).downto(0) do |i|
    !!         break if is_code?(i)
    !!         @coverage[i] ||= :inferred
    !!       end
    !!     end
	   (0...lines.size).each do |i|
	     next if @coverage[i]
	     line = @lines[i]



License
-------
rcov is released under the terms of Ruby's license.
rcov includes xx 0.1.0, which is subject to the following conditions:

ePark Labs Public License version 1
Copyright (c) 2005, ePark Labs, Inc. and contributors
All rights reserved.

Redistribution and use in source and binary forms, with or without modification,
are permitted provided that the following conditions are met:

  1. Redistributions of source code must retain the above copyright notice, this
     list of conditions and the following disclaimer.
  2. Redistributions in binary form must reproduce the above copyright notice,
     this list of conditions and the following disclaimer in the documentation
     and/or other materials provided with the distribution.
  3. Neither the name of ePark Labs nor the names of its contributors may be
     used to endorse or promote products derived from this software without
     specific prior written permission.

THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

