Lux (LUcid eXpect scripting) simplifies test automation and provides an Expect-style execution of commands
Erlang HTML C Other
Latest commit 25fb7ca Mar 23, 2017 @hawk Version 1.16.1


Lux (LUcid eXpect scripting) provides scripting with an Expect-style execution of commands in a powerful but simple fashion. See [Expect][] for more info about the origin.

With Lux it is possible to

  • simplify automated testing
  • control interactive programs by sending textual input to them and using [regular expression][]s to ensure that their output matches the expectations
  • perform detailed post mortem analyzis of test suite results
  • interactively debug and trace single test cases
  • get editor support for editing scripts by using the [Emacs][] mode

The tool is written in [Erlang/OTP][] and requires its runtime environment.

See the file lux.html for the full documentation or view it online on GitHub.

A sample script

Here is an example of a test script (lux/examples/intro.lux). It starts couple of concurrent shells and sends text to them with the ! command and matches expected output with ?.

[doc Test of single and multi line regular expressions]

# A global variable is accessible in all shells
[global file=removeme.txt]

[shell single]
    # The terminal echoes all input
    !echo foo
    ?echo foo

[shell multi]
    # bar is indented 4 characters
    !echo "foo"      > $file
    !echo "    bar" >> $file
    !echo "fum"     >> $file
    !cat $file

    # The first double quote char defines the
    # first column of the multi line regexp

# Let single be the active shell again
[shell single]

# Cleanup is always executed, regardless if the script succeeds or fails
    # Match of command exit status. Observe the double dollar sign.
    !rm -f $file
    !echo ==$$?==

How to run the script

Run a single script like this:

/home/hm> lux lux/examples/intro.lux

summary log       : /home/hm/lux_logs/run_2012_03_22_12_44_42/lux_summary.log

test case         : /home/hm/lux/examples/intro.lux
progress          : ..:..:....:.....:...:...:..:..:..:.....c......:...:...:..:....
result            : SUCCESS

successful        : 1
summary           : SUCCESS



In this run we got a (brief) progress report of the test case on stdout and a link to a summary log containing (lots of) details. How to assemble the history of multiple runs

In a nightly build environment it might be difficult to pinpoint when a certain test case/suite started to fail. This process is greatly simplified by running lux with the --history option as it will assemble all test results as a timeline (interleaved with changeset identities if provided with --revision).

/home/hm> lux --revision svn_4711 --run jenkins_17 lux/examples
/home/hm> lux --revision svn_4712 --run jenkins_20 lux/examples/intro.lux
/home/hm> lux --revision svn_4712 --run jenkins_20 lux/examples/fail.lux
/home/hm> lux --revision svn_4715 --run jenkins_22 lux/examples
/home/hm> lux --history .
Assembling history of logs in /home/hm.......4 test runs...ok