Silent failure with invalid k-mer size, hangs with kmer size zero

[peterjc]

This works, using -k 16 which is documented in the fastANI -h help as the maximum:

❯ fastANI -v
version 1.33

❯ fastANI -q MGV-GENOME-0264574.fas -r MGV-GENOME-0266457.fna -k 16 -o /dev/stdout ; echo "Return code $?"
>>>>>>>>>>>>>>>>>>
Reference = [MGV-GENOME-0266457.fna]
Query = [MGV-GENOME-0264574.fas]
Kmer size = 16
Fragment length = 3000
Threads = 1
ANI output file = /dev/stdout
Sanity Check  = 0
>>>>>>>>>>>>>>>>>>
INFO [thread 0], skch::main, Count of threads executing parallel_for : 1
INFO [thread 0], skch::Sketch::build, window size for minimizer sampling  = 24
INFO [thread 0], skch::Sketch::build, minimizers picked from reference = 3186
INFO [thread 0], skch::Sketch::index, unique minimizers = 3184
INFO [thread 0], skch::Sketch::computeFreqHist, Frequency histogram of minimizers = (1, 3182) ... (2, 2)
INFO [thread 0], skch::Sketch::computeFreqHist, consider all minimizers during lookup.
INFO [thread 0], skch::main, Time spent sketching the reference : 0.00338479 sec
INFO [thread 0], skch::main, Start Map 1
INFO [thread 0], skch::main, Time spent mapping fragments in query #1 : 0.0054579 sec
INFO [thread 0], skch::main, Time spent post mapping : 1.1101e-05 sec
INFO [thread 0], skch::main, ready to exit the loop
INFO, skch::main, parallel_for execution finished
MGV-GENOME-0264574.fas  MGV-GENOME-0266457.fna  99.5014 12      13
Return code 0

However, trying a larger value like -k 17 gives the following:

❯ fastANI -q MGV-GENOME-0264574.fas -r MGV-GENOME-0266457.fna -k 17 -o /dev/stdout ; echo "Return code $?"
>>>>>>>>>>>>>>>>>>
Reference = [MGV-GENOME-0266457.fna]
Query = [MGV-GENOME-0264574.fas]
Kmer size = 17
Fragment length = 3000
Threads = 1
ANI output file = /dev/stdout
Sanity Check  = 0
>>>>>>>>>>>>>>>>>>
INFO [thread 0], skch::main, Count of threads executing parallel_for : 1
INFO [thread 0], skch::Sketch::build, window size for minimizer sampling  = 33
INFO [thread 0], skch::Sketch::build, minimizers picked from reference = 2304
INFO [thread 0], skch::Sketch::index, unique minimizers = 2303
INFO [thread 0], skch::Sketch::computeFreqHist, Frequency histogram of minimizers = (1, 2302) ... (2, 1)
INFO [thread 0], skch::Sketch::computeFreqHist, consider all minimizers during lookup.
INFO [thread 0], skch::main, Time spent sketching the reference : 0.00330126 sec
INFO [thread 0], skch::main, Start Map 1
INFO [thread 0], skch::main, Time spent mapping fragments in query #1 : 0.00448644 sec
INFO [thread 0], skch::main, Time spent post mapping : 1.0888e-05 sec
INFO [thread 0], skch::main, ready to exit the loop
INFO, skch::main, parallel_for execution finished
MGV-GENOME-0264574.fas  MGV-GENOME-0266457.fna  99.4869 12      13
Return code 0

There is no error - the return code is zero - and there is no error message.

There is nothing in the output file (which is fine).

Similarly for -k -1, -k 2 and -k 3.

However, using -k 0 seems to hang.