Run Tests - Without Focus Loss!
By Tor Norbye on May 14, 2009
I like unit tests - but running them can be painful. Commit-validation tests
which bring up UI are obviously annoying, but even simple unit tests that
get in the way. Does this look familiar?
The above menubar should look familiar to anyone on a Mac who's run unit tests for client side
Java code. Not necessarily GUI tests, just any test where GUI libraries are loaded.
For every testcase, the test runner fires up a new process, which tells
OSX that "I'm graphical, give me focus!", and this steals the focus from the user.
The test finishes quickly thereafter, the process quits - and then the test runner
goes to the next test and the whole cycle starts over.
This is really painful because I like to have lots of tests. The Python editor support
for Netbeans had 600+ tests;
the Ruby support even higher than that. Whenever I run tests, I basically have to
fight with my computer to get focus. Forget trying to write anything - every second
or so my keystrokes get stolen as the next test grabs focus - so I've gotten in
the habit of using the time for browsing, since I'm mostly reading, and I can handle
clicking a link a second time if the first click got lost. But every now and then
somebody will ping me on instant messaging - and it's maddening trying to respond while
this is going on.
If this is sounding painfully familiar to you, I have good news. I've finally figured
out a setup where this is no longer a problem!
The key discovery was that I can run my tests from another account on the system.
With OSX' fast user switching, I can switch to the alternate account, launch the
unit tests, and return back to my regular account where the tests won't interfere
with display focus. In order to let me run my tests from that other account, I
just open a terminal there and
su -l tor in the shell to run all the
commands (or NetBeans) as myself.
This was a huge improvement since it removes the 10-30 minutes testrun downtime.
But it had some disadvantages - first, I don't like running tests from a shell, and second,
it's hard to know when things finish - and switching back and forth to check is annoying
since I always have passwords on my accounts so the machine isn't open.
So the second step was to set up Hudson (a
continuous integration server that is trivial to setup, and has a huge number of
plugins which makes
graphing code coverage, unit tests, findbugs results, integrating with version control
systems etc trivial. And it's
not just for Java developers.)
Instead of logging into the other account
for each test run, I log into the other account once, and start up Glassfish
with Hudson running. From now on I can access, configure and launch builds right
from my own browser in my primary account. The key step here is that Glassfish was
started from the secondary account, so its primary display is associated with the builder account.
When my build in Glassfish gets to the test stage, it's actually doing the display
connection just as before, and if I log into the secondary account, I get the annoying
focus flashing just as before. Look - the tested process is a user visible application in the dock:
Another improvement which really helped is the "File System" version control plugin for Hudson.
I want my Hudson builds to build my current working copy. I don't want to
check my code into Mercurial (even a local repository) just so that Hudson can
grab the code and build it. I want Hudson to build my current changes - my current
edits. After all, I'm trying to test them before checking in! And I discovered that
there is a plugin which will let me do that - it's just
a "file system" version control wrapper - which means you just point Hudson to your local
directory, and off it goes. When the build starts, it makes a quick disk-copy of the
source tree. Even though Mercurial cloning is pretty fast, this is even faster.
The disk copy also lets me specify a filter of files to exclude, so I had it ignore
\*.class files. The diskcopy only takes 10 seconds or so before the build kicks
off, and it's building a snapshot of my current in-progress, edited working copy!
(It can also just update the copy based on changed filestamps - that's even faster,
but it didn't seem to correctly delete removed files, so I let it start from scratch
(Note - this plugin isn't in the catalog that you can browse right from within the
Manage Plugins page within Hudson; I downloaded the .hpi file from
and installed it in the Advanced tab.)
The final ingredient is the new Hudson support in NetBeans 6.7. I don't even have
to go to the browser to kick off build jobs. I just point NetBeans to my Hudson
server once, and from then on I have full Hudson integration. When I want to
run my tests I just select Launch job:
I get notified if there's a problem:
I can look at failures and logs:
I can see build logs etc. directly in the output window, and hyperlinks warp to directly to files - to the files as they were in the build, not the current state:
So to recap - with this setup, as I'm editing my code and I want to check the tests,
I just right click on a node and say "Start Job" - and off it goes without bothering
me at all - no more focus interruptions, and no more GUI windows popping up from
interactive tests. It's trivial to check the results. And it's even added one more
level of convenience: I have multiple projects, each with unit tests, and from the
IDE I couldn't have them all run with a single gesture. My build job does that.
I'm really stoked! I was at one point able to do this when I was working on Linux
and Solaris by setting my $DISPLAY variable and doing tricks with VNC. But that
still required my tests to run in a console - which made interpreting the results sucky.
If you haven't played with Hudson, try it - it's unbelievably easy to set up. Just download
the Glassfish appserver and install it, download the Hudson .war file, and drop the hudson.war
into the autodeploy directory of the appserver, and browse to
Once you're there you can install
plugins (under Manage hudson), point to your local installations of the JDK, ant,
etc., and configure your build jobs by running scripts, launching maven scripts, writing
ruby scripts, or obviously running ant scripts.
Some final miscellaneous tips:
- I don't want Time Machine to back up my builds trees, or Spotlight to
index data in these directories, so I went to the TimeMachine preferences and had it
- I did the same thing for Spotlight - but unlike
the Time Machine preferences, there was no checkbox to "Display Invisible Files" (e.g.
files that start with a dot, such as
.hudson) in its file chooser. Here's a tip I didn't
learn until recently: When a Mac filechooser has focus, you can press slash (/) - and this
will open a text field where you can directly type the path it should jump to. I typed
/Users/tor/.hudsonand from there I was able to select the jobs directory to exclude.
- You might be tempted to skip the "filesystem version control" plugin and just have
your build symlink to your working copy. Be careful; if Hudson is configured to delete
older builds you might find yourself without your source code. I'm not saying it will
follow your symlinks - Java has support for symlinks now - but I haven't tried it, and
I have been bitten by
antin the past where it decided to follow symlinks in its
zeal to delete recursively!
I recently discovered that you can reorder the build steps in a Hudson job. The little
graphic to the left of a build task is a handle you can just drag to reorder!