Printing of error in doctest

[fredrikekre]

The following doctest, taken from julia base

```jldoctest
julia> struct MyException <: Exception
           msg::AbstractString
       end

julia> function Base.showerror(io::IO, err::MyException)
           print(io, "MyException: ")
           print(io, err.msg)
       end

julia> err = MyException("test exception")
MyException("test exception")

julia> sprint(showerror, err)
"MyException: test exception"

julia> throw(MyException("test exception"))
ERROR: MyException: test exception
```

fails on the last expression. Instead of ERROR: MyException: test exception Documenter evaluates to MyException("test exception") so somehow we never end up in the custom showerror function.

[fredrikekre]

Probably some logic that is incorrect here

Documenter.jl/src/DocChecks.jl

Lines 288 to 298 in 56e9f62

	function error_to_string(buf, er, bt)
	fs = funcsym()
	# Remove unimportant backtrace info.
	index = Compat.findlast(ptr -> Documenter.ip_matches_func(ptr, fs), bt)
	# Print a REPL-like error message.
	disable_color() do
	print(buf, "ERROR: ")
	showerror(buf, er, index === nothing ? bt : bt[1:(index - 1)])
	end
	sanitise(buf)
	end

[mortenpi]

It's not related to world-age stuff by any chance? showerror might need Base.invokelatest?

[fredrikekre]

Ah, good catch! That fixes it.