Testsystem has false positive
My test has a line
$result+=jt::test_grepnumber("$workdir/out", "distance of charge densitie", "22: *([^ ]*)", 0.000002, 0.0001);
If the code doesn't reach the 22nd iteration this is the output:
10/01/2019 11:34:01--Grep for distance of charge densitie in /Users/redies/fleur/build.gfort.debug/Testing/work/out: == 2e-06:ok
It seems perl reads an empty string as 0, which passes the test. I think this is clearly not intended behaviour.