Literal character incorrectly parsed as layout

[MeAmAnUsername]

Summary

The character - (unary minus) is ignored / parsed as layout

What you did

SDF3:

context-free syntax
  Exp.Num = NAT
  Exp.UnaryMinus = [-[e:Exp]] {layout(indent "-" e && offside "-" e)}
lexical syntax
  NAT = [0-9]+
  LAYOUT = [\ \n\t\v\f\r]

Example file:

-
80

Note the trailing newline in the example file.

What you expected to happen

Parsed as Program(UnaryMinus(Num("80")))

What actually happened

Parsed as Program(Num("80"))

Context

• Spoofax version: Spoofax-pie 0.19.2
• Operating system & version: MacOS Mojave, 10.14.6 (18G9323)
• Java version (if applicable): 11 (bundled with Spoofax)
• Eclipse version (if applicable): 4.23.0.20220310-1200
• Gradle version (if applicable): N.A.

Additional information

The layout constraint is important.
The problem does not occur with slightly different inputs. All of the following are expected:
-80 is correctly parsed as Program(UnaryMinus(Num("80"))), regardless of trailing layout

-
 80

80 is indented. This is also correctly parsed as Program(UnaryMinus(Num("80"))).

-
80

No newline after 80. Fails to parse (expected, the offside constraint requires that the 80 is indented). Other layout such as spaces after the 80 gives same result.

-
80
 

Newline with space after 80 fails to parse. Spaces between 80 and newline do not matter (still fails to parse).