Triple quoted strings and raw interpolated strings swallow trailing backslash and emit spurious warning

[japgolly]

reproduction steps

"""\/ \/ /\"""

problem

scala> """\/ \/ /\"""
                ^
       warning: Unicode escapes in triple quoted strings are deprecated, use the literal character instead

expectation

Silence from scalac. I'm not using a unicode escape.

[SethTisue]

2.13.2 regression. @martijnhoekstra want to take a look...?

[martijnhoekstra]

darn.

[martijnhoekstra]

The spurious warning is the least problematic part of the bug.

scala> """\/ \/ /\"""
                ^
       warning: Unicode escapes in triple quoted strings are deprecated, use the literal character instead
val res0: String = \/ \/ /

scala> raw"\/ \/ /\"
                 ^
       warning: Unicode escapes in raw interpolations are deprecated. Use literal characters instead.
val res4: String = \/ \/ /

[martijnhoekstra]

When a string or raw interpolator ends with a backslash, that backslash is swallowed if there are additional backslashes in the string, at least 5 positions before the end.