pegasus-dot Unhandled exception NilAssertionError

[masukomi]

Attempting to generate a dot file with the json generated from arithmetic.grammar results in an error.

Reproducing:

❯ bin/pegasus < grammars/arithmetic.grammar > grammars/arithmetic.json
❯ bin/pegasus-dot < grammars/arithmetic.json
digraph G {
  q1 -> q5 [label="open_parenth"]
  q1 -> q6 [label="number"]
Unhandled exception: Nil assertion failed (NilAssertionError)
  from /opt/homebrew/Cellar/crystal/1.5.0/share/crystal/src/array.cr:1143:18 in '__crystal_main'
  from /opt/homebrew/Cellar/crystal/1.5.0/share/crystal/src/crystal/main.cr:115:5 in 'main'

crystal info:

❯ crystal --version
Crystal 1.5.0 (2022-07-06)

LLVM: 14.0.6
Default target: aarch64-apple-darwin21.5.0

[DanilaFe]

Thank you for the thorough report! I'll take a look as soon as I have time.

[DanilaFe]

I believe this is fixed by 5820a51. Sorry it took so long! It was a pretty straightforward bug; I just haven't had a lot of time to maintain pegasus.