moonbitlang / core / 7023

90%

push

github

fix(regex): an unknown escape in a character class is an error (#4378)

* fix(regex): an unknown escape in a character class is an error

Inside a class, an escape the parser did not know was read as a backslash
followed by the next character, with no error. `[\v]` matched `\` and `v`
where a regex literal matches a vertical tab, `[\0]` matched `\` and `0`,
and `[\p{L}]` matched five literal characters. Outside a class the same
escapes were already errors.

- `\v` is accepted in a class, as it is outside one.
- Every other unknown escape in a class raises `Invalid escape sequence`.
- A range cut off by the end of the pattern, as in `[a-`, raised nothing
  and aborted the program. It raises `Unclosed character class`.

* test(regex): word the class escape comments more exactly

2 of 2 new or added lines in 1 file covered. (100.0%)

16738 of 18710 relevant lines covered (89.46%)

377530.51 hits per line