Rcov 0.3.0 (code coverage tool): happier Rails

Ruby
1

Source code, additional information, screenshots… available at
eigenclass.org
Release information:
eigenclass.org

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 tool for simple code coverage analysis in Ruby. It features:

  • fast execution: 20-300 times faster than previous tools
  • multiple analysis modes
  • more accurate coverage information through code linkage inference
    using
    simple heuristics
  • XHTML, plain text, ANSI-escaped text outputs
  • convenient interface
  • colorblind-friendliness

What’s new in 0.3.0

A change summary can be found at
http://eigenclass.org/hiki.rb?rcov+0.3.0

Even shorter summary:

rcov 0.3.0 introduces a number of features that simplify the analysis of
Rails
applications.

The new code coverage analysis mode, --test-unit-only, records
exclusively code
executed inside Test::Unit::TestCase(s). Another important addition is
the
ability to detect aliased source files: this was very needed to analyze
Rails
apps, where a file could get loaded under several different names, due
to the
extensive usage of #require with relative paths.

Features
* --exclude-only
* consolidate multiple references to the same underlying .rb file
(much needed for Rails)
* --test-unit-only
Fixes
* consider and/op operators
* honor --no-color in (rich) text mode
* output valid XHTML indices

Thanks (do tell if I forgot to list your name)

Tom Dolbilin:

  • identified and fixed backslash problem on win32 for generated
    filenames

Andrew K.:

  • made the index XHTML compliant
  • consolidate multiple references to the same underlying .rb file

Robert F.:

  • pointed me to dynamic uses of the tracing hooks, provided the
    inspiration
    for RCOV__.run_hooked

Downloading

The last version is available at
eigenclass.org

How do I use it? What does it look like?

Just use rcov to run your program (instead of ruby), and a number of
XHTML
files with the code coverage information will be generated, e.g.

rcov test/*.rb

will execute all the .rb files under test/ and generate the code
coverage report
under coverage/. rcov can also operate in “bogo-profiling mode”
and output the relevant information in alternative formats (for the time
being, plain text with execution count annotations and colored text).
Use
rcov -h
for more information.

Sample output

See eigenclass.org (once again) for screenshots.
The (undecorated) textual output with execution count information looks
like this:

$ rcov --no-html -t 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

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.