Documentation for escape_string is inaccurate

[KristofferC]

escape_string([io,] str::AbstractString[, esc::AbstractString]) -> AbstractString

Note the return value. Nope:

julia> typeof(escape_string(IOBuffer(), "abc", "ab"))
Void

[KristofferC]

Also, this should work?

julia> escape_string("foo", "f")
ERROR: MethodError: no method matching escape_string(::String, ::String)
Closest candidates are:
  escape_string(::Any, ::AbstractString, ::AbstractString) at strings/io.jl:233
  escape_string(::AbstractString) at strings/io.jl:249

[carstenbauer]

Similar inconsistencies with unescape_string.

I will try to fix those issues and make a PR as soon as possible.

[carstenbauer]

Because of #16603, I will not split up the existing function into a print_escape_string (with return type Void) and a function escape_string (with return type AbstractString). Instead I will adjust the documentation to indicate that depending on wether an io is given the return type differs.

I will also fix the escape_string("foo", "f") issue by defining a corresponding variant of escape_string.

[KristofferC]

Fixed by #24539