It also features alphabet normalization to simplify test cases that could not be further shortened.

Example

$ cat testcase.in
This is a lengthy and annoying hello world testcase.

$ cat testme.sh
#!/bin/bash

grep "el..*wo" || exit 0
exit 1

$ ../tmin -x ./testme.sh
tmin - complex testcase minimizer, version 0.03-beta (lcamtuf@google.com)
[*] Stage 0: loading 'testcase.in' and validating fault condition...
[*] Stage 1: recursive truncation (round 1, input = 53/53)
[*] Stage 1: recursive truncation (round 2, input = 27/53)
[*] Stage 1: recursive truncation (round 3, input = 14/53)
[*] Stage 1: recursive truncation (round 4, input = 10/53)
[*] Stage 1: recursive truncation (round 5, input = 8/53)
[*] Stage 1: recursive truncation (round 6, input = 7/53)
[*] Stage 2: block skipping (round 1, input = 7/53)
[*] Stage 2: block skipping (round 2, input = 6/53)
[*] Stage 2: block skipping (round 3, input = 5/53)
[*] Stage 3: alphabet normalization (round 1, charset = 5/5)
[*] Stage 3: alphabet normalization (round 2, charset = 5/5)
[*] Stage 4: character normalization (round 1, characters = 4/5)
[*] All done - writing output to 'testcase.small'...

== Final statistics==
 Original size : 53 bytes
Optimized size : 5 bytes (-90.57%)
Chars replaced : 1 (1.89%)
    Efficiency : 9 good / 49 bad
  Round counts : 1:6 2:3 3:2 4:1

$ cat testcase.small
el0wo

You can download Tmin 0.03 here:

tmin-0.03.tar.gz

Or read more here.