config: add an option to ignore diagnostics warnings

Add an option, g:go_diagnostics_ignore_warnings, to allow diagnostics
provided by gopls to be ignored.

When set, warnings provided by gopls will be neither highlighted nor
shown in the quickfix window after running `:GoDiagnostics` or using
`gopls` as the metalinter.

Closes #2636

Author: bhcleek

autoload/go/config.vim

@@ -576,6 +576,10 @@ function! go#config#DiagnosticsEnabled() abort
   return get(g:, 'go_diagnostics_enabled', 0)
 endfunction
 
+function! go#config#DiagnosticsIgnoreWarnings() abort
+  return get(g:, 'go_diagnostics_ignore_warnings', 0)
+endfunction
+
 function! go#config#GoplsOptions() abort
   return get(g:, 'go_gopls_options', ['-remote=auto'])
 endfunction

autoload/go/lint.vim

@@ -144,15 +144,16 @@ function! go#lint#Diagnostics(bang, ...) abort
 
   let l:listtype = go#list#Type("GoDiagnostics")
 
-  if len(l:messages) == 0
+  " Parse and populate the quickfix list
+  let l:winid = win_getid(winnr())
+  call go#list#ParseFormat(l:listtype, l:errformat, l:messages, 'GoDiagnostics', 0)
+
+  let l:errors = go#list#Get(l:listtype)
+
+  if len(l:errors) == 0
     call go#list#Clean(l:listtype)
     call go#util#EchoSuccess('[diagnostics] PASS')
   else
-    " Parse and populate the quickfix list
-    let l:winid = win_getid(winnr())
-    call go#list#ParseFormat(l:listtype, l:errformat, l:messages, 'GoDiagnostics', 0)
-
-    let errors = go#list#Get(l:listtype)
     call go#list#Window(l:listtype, len(errors))
 
     if a:bang
@@ -467,7 +468,11 @@ function! s:errorformat(metalinter) abort
   elseif a:metalinter == 'staticcheck'
     return '%f:%l:%c:\ %m'
   elseif a:metalinter == 'gopls'
-    return '%f:%l:%c:%t:\ %m,%f:%l:%c::\ %m,%f:%l::%t:\ %m'
+    let l:efm = ''
+    if go#config#DiagnosticsIgnoreWarnings()
+      let l:efm = '%-G%f:%l:%c:W:\ %m,%-G%f:%l::W:\ %m,'
+    endif
+    return l:efm . '%f:%l:%c:%t:\ %m,%f:%l:%c::\ %m,%f:%l::%t:\ %m'
   endif
 endfunction
 

autoload/go/lsp.vim

@@ -1393,7 +1393,9 @@ function! s:highlightMatches(errorMatches, warningMatches) abort
     call go#util#ClearHighlights('goDiagnosticWarning')
     if go#config#HighlightDiagnosticWarnings()
       let b:go_diagnostic_matches.warnings = copy(a:warningMatches)
-      call go#util#HighlightPositions('goDiagnosticWarning', a:warningMatches)
+      if !go#config#DiagnosticsIgnoreWarnings()
+        call go#util#HighlightPositions('goDiagnosticWarning', a:warningMatches)
+      endif
     endif
   endif
 

doc/vim-go.txt

@@ -1939,6 +1939,14 @@ By default it is disabled.
 >
   let g:go_diagnostics_enabled = 0
 <
+                                        *'g:go_diagnostics_ignore_warnings'*
+
+Specifies whether warnings from  `gopls` diagnostics are ignored.
+
+By default it is disabled.
+>
+  let g:go_diagnostics_ignore_warnings = 0
+<
 
                                                   *'g:go_template_autocreate'*