Fix UTF-8 validation and file IO error checking

[davidanthoff]

When I added the more specific error handlers, I forgot to also adjust the validation phase accordingly. Fixes a bug from crash reporting.

I added some stuff, namely it is now also handling SystemError properly, because those can also happen from file IO problems.

[codecov]

Codecov Report

Merging #588 into master will decrease coverage by 0.03%.
The diff coverage is 0%.

@@            Coverage Diff             @@
##           master     #588      +/-   ##
==========================================
- Coverage   29.12%   29.08%   -0.04%     
==========================================
  Files          23       23              
  Lines        1686     1688       +2     
==========================================
  Hits          491      491              
- Misses       1195     1197       +2

Impacted Files	Coverage Δ
src/requests/textdocument.jl	53.18% <0%> (ø)	⬆️
src/requests/init.jl	17.91% <0%> (ø)	⬆️
src/staticlint.jl	15.62% <0%> (ø)	⬆️
src/requests/workspace.jl	0% <0%> (ø)	⬆️

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[ZacLN]

Could we not re-throw here? This is part of the speculative parent search, if it not a valid file lets just ignore it

I missed this first time around but have just been bitten by it.

[ZacLN]

Not quite sure if those comments are clear: could we avoid rethrowing the error on lines 408 and 427 of textdocument.jl

[davidanthoff]

Not quite sure if those comments are clear: could we avoid rethrowing the error on lines 408 and 427 of textdocument.jl

So that is the idea: it will not rethrow for IOError (and now SystemError), but for any other error it will rethrow (under the assumption that that would indicate a problem unrelated to file IO which we want to see in the crash reports).

[ZacLN]

Ah got you! ignore me..

[davidanthoff]

:) can you approve?