Panic when trying to load (invalid) file with spaces between bit value and wire ID

[andreasWallner]

Wellen panics when trying to load a (admittedly invalid) vcd file that contains spaces on single-bit lines in the file.

Reproduced with surfer using this vcd:

$version Generated manually $end
$timescale 1s $end

 $scope module logic $end
  $var wire  8 # data [7:0] $end
  $var wire  1 $ data_valid $end
 $upscope $end
$enddefinitions $end

#0
b00000011 #
1 $
#10
b11000011 #
#20
0 $
#30
b00111100 #
1 $
#40

which the panic:

thread '<unnamed>' panicked at /home/uhu01/.cargo/registry/src/index.crates.io-6f17d22bba15001f/wellen-0.9.14/src/vcd.rs:979:51:
called `Option::unwrap()` on a `None` value

I would expect an error message instead of the panic.

[ekiwi]

Thanks! I will try to figure out how to handle this more gracefully. Have you encountered this problem with any tool that produces VCDs? Does this load in GTKWave? I am trying to decide whether we should try to parse this, even if it is technically wrong, or if it is enough to just not crash and return an error instead.

[andreasWallner]

It was from a hand-written VCD that I typed up for testing Surfer... I don't think there is much reason to support this, gtkwave silently fails to load it

[ekiwi]

OK. Thanks! Sounds like the goal here is to return an error instead of crashing.

[JabulaniNgcobo]

18