# Rcov 0.6.0: "differential code coverage", full (faster) cros **URL:** \ **Category:** Ruby\ **Created:** [June 12, 2006, 11:43am UTC](https://www.ruby-forum.com/t/rcov-0-6-0-differential-code-coverage-full-faster-cros/63114 "2006-06-12T11:43:02Z")\ **Posts on this page:** 5\ **Page:** 1
**Author:** ![tulkas](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/t/5daacb/32.png) [@tulkas](https://www.ruby-forum.com/u/tulkas)\ **Post date:** [June 12, 2006, 11:43am UTC](https://www.ruby-forum.com/t/rcov-0-6-0-differential-code-coverage-full-faster-cros/63114/1 "2006-06-12T11:43:02Z")
Source code, additional information, screenshots… available at [eigenclass.org](http://eigenclass.org/hiki.rb?rcov) Release information: [eigenclass.org](http://eigenclass.org/hiki.rb?rcov+0.6.0) Sample (fully) cross-referenced report at [eigenclass.org](http://eigenclass.org/static/rcov-sample-report-full-crossref/) This release includes two RubyGems packages: a binary one for Win32 and a platform-independent one for all those with a compiler, (or a lot of patience, if willing to run rcov in pure-Ruby mode), so gem install rcov should work. # 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 # What’s new in 0.6.0 See [eigenclass.org](http://eigenclass.org/hiki.rb?rcov+0.6.0) for the detailed change summary. 0.6.0 features a new differential coverage mode (–text-coverage-diff/-D) which will tell you when you’ve added new code that was not covered by the tests: !!! Uncovered code introduced in app/models/article.rb ``` ### app/models/article.rb:44 # Find all articles on a certain date def self.find_all_by_date(year, month = nil, day = nil) !! from, to = self.time_delta(year, month, day) !! Article.find(:all, :conditions => ["articles.created_at ``` BETWEEN ? AND ? AND articles.published != 0", from, to], :order =\> ‘articles.created\_at DESC’, :include =\> [:categories, :trackbacks, :comments]) !! end ``` # Find one article on a certain date ``` rcov 0.6.0 ships with a compiler plugin for integration with vim (contributions for other editors/IDEs welcome). Cross-referenced reports, which were recently introduced, have been expanded to indicate where methods are called from and which methods were called for each line (–xrefs). In addition to that, cross-referenced report generation is now over 4 times faster for applications with deep call stacks (such as Rails apps) # Downloading The last version is available at [eigenclass.org](http://eigenclass.org/hiki.rb?rcov) # 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 [eigenclass.org](http://eigenclass.org/hiki.rb?rcov) (once again) for screenshots. Take a look at a sample code coverage report generated by rcov at [eigenclass.org](http://eigenclass.org/static/rcov-sample-report-full-crossref/) 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] # Thanks Alex W.: - reported problem with heredocs: they were not being marked as a whole if the “header” wasn’t reported by Ruby. - reported problem with the last line of literal data structs not being covered if there was stuff after the end delimiter Coda Hale: - reported problem with blocks were the first line is not being marked and ditto for the last line when end/} is followed by more stuff Tim Shadel: - reported that the last comment block was not being marked even when it was the last thing in the file ## 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. ---
**Author:** ![tulkas](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/t/5daacb/32.png) [@tulkas](https://www.ruby-forum.com/u/tulkas)\ **Post date:** [June 12, 2006, 10:58pm UTC](https://www.ruby-forum.com/t/rcov-0-6-0-differential-code-coverage-full-faster-cros/63114/2 "2006-06-12T22:58:04Z")
On 6/12/06, Mauricio F. [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) wrote: > Source code, additional information, screenshots… available at > [eigenclass.org](http://eigenclass.org/hiki.rb?rcov) > Release information: > [eigenclass.org](http://eigenclass.org/hiki.rb?rcov+0.6.0) > > Sample (fully) cross-referenced report at > [eigenclass.org](http://eigenclass.org/static/rcov-sample-report-full-crossref/) > [snip] nice cross-referencing, when clicking on a method you can see who calls it, and which methods it calls. Well done 🙂 ---
**Author:** ![tulkas](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/t/5daacb/32.png) [@tulkas](https://www.ruby-forum.com/u/tulkas)\ **Post date:** [June 12, 2006, 11:24pm UTC](https://www.ruby-forum.com/t/rcov-0-6-0-differential-code-coverage-full-faster-cros/63114/3 "2006-06-12T23:24:30Z")
It just keeps getting better and better! I just ran my first xref in rcov, and I’d like to request that the file reference box that appears should (soft) wrap the filenames. I have some long paths, and the filename goes way off the browser window. Please feel free to contact me off list for a screen shot. Otherwise, I’m loving it! Thanks! Sean ---
**Author:** ![tulkas](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/t/5daacb/32.png) [@tulkas](https://www.ruby-forum.com/u/tulkas)\ **Post date:** [June 14, 2006, 9:29am UTC](https://www.ruby-forum.com/t/rcov-0-6-0-differential-code-coverage-full-faster-cros/63114/4 "2006-06-14T09:29:29Z")
On Tue, Jun 13, 2006 at 05:56:37AM +0900, Simon S. wrote: > nice cross-referencing, when clicking on a method you can see who > calls it, and which methods it calls. Well done 🙂 Just trying to improve the code for XHTML generation you wrote originally 😉 ---
**Author:** ![tulkas](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/t/5daacb/32.png) [@tulkas](https://www.ruby-forum.com/u/tulkas)\ **Post date:** [June 14, 2006, 9:32am UTC](https://www.ruby-forum.com/t/rcov-0-6-0-differential-code-coverage-full-faster-cros/63114/5 "2006-06-14T09:32:41Z")
On Tue, Jun 13, 2006 at 06:23:01AM +0900, Sean H. wrote: > It just keeps getting better and better! > > I just ran my first xref in rcov, and I’d like to request that the > file reference box that appears should (soft) wrap the filenames. I > have some long paths, and the filename goes way off the browser > window. Do you have a patch to the CSS handy? (another option would be truncating filenames and maybe adding an onmouseover popup)