feat(diagnostic): add showRelatedInformation

[hexh250786313]

See: #5086

[codecov]

Codecov Report

Attention: Patch coverage is 56.52174% with 10 lines in your changes missing coverage. Please review.

Project coverage is 98.47%. Comparing base (33d0a52) to head (51d54c1).

Files	Patch %	Lines
src/diagnostic/buffer.ts	43.75%	8 Missing and 1 partial ⚠️
src/language-client/client.ts	0.00%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #5090      +/-   ##
==========================================
- Coverage   98.51%   98.47%   -0.05%     
==========================================
  Files         273      273              
  Lines       26091    26088       -3     
  Branches     5391     5389       -2     
==========================================
- Hits        25704    25690      -14     
- Misses        229      238       +9     
- Partials      158      160       +2     

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[fannheyward]

screenshot please, for better understanding.

[hexh250786313]

@fannheyward Screenshots added.

[fannheyward]

Shall we remove the separateRelatedInformationAsDiagnostics? This new configuration controls to display related in floating window, I'd prefer to remove the old configuration, which only separates them but doesn't shows in relation.

[hexh250786313]

@fannheyward Removing the separateRelatedInformationAsDiagnostics feature is ok, the separated diagnostic doesn't really provide much useful information:

If we need to find the related diagnostic, we can just use :CocCommand workspace.diagnosticRelated.

Moreover, for some reason, the separateRelatedInformationAsDiagnostics only works for customized language services configured by coc-settings.json, not for some of plug-in language servers (e.g. coc-tsserver). See: #5078

I will make a commit for it shortly.

[fannheyward]

the separated diagnostic doesn't really provide much useful informatio

Yes, this is what I said not showing in relation.