feat: apply lsp commands (#1130)

* Apply commands from the lsp

If the lsp returns commands to run on completion, we now execute them.
This is helpful for the Haskell language server which uses commands to
implement auto-importing.

* Update checkbox

* fix: run callback after executing LSP command

---------

Co-authored-by: Liam Dyer <[email protected]>

docs/development/lsp-tracker.md

@@ -65,5 +65,5 @@
 - [x] `textEditText`
 - [x] `additionalTextEdits` <- known issue where applying the main text edit will cause this to be wrong if the additional text edit comes after since the indices will be offset
 - [ ] `commitCharacters`
-- [ ] `command`
+- [x] `command`
 - [x] `data` <- Don't think there's anything special to do here

lua/blink/cmp/sources/lib/provider/init.lua

@@ -158,7 +158,7 @@ function source:execute(context, item)
   if self.module.execute == nil then
     return async.task.new(function(resolve) resolve() end)
   end
-  return async.task.new(function(resolve) self.module:execute(context, item, resolve) end)
+  return async.task.new(function(resolve) return self.module:execute(context, item, resolve) end)
 end
 
 --- Signature help ---

lua/blink/cmp/sources/lsp/init.lua

@@ -147,4 +147,15 @@ function lsp:get_signature_help(context, callback)
   end)
 end
 
+--- Execute ---
+
+function lsp:execute(_, item, callback)
+  local client = vim.lsp.get_client_by_id(item.client_id)
+  if client and item.command then
+    client.request('workspace/executeCommand', item.command, function() callback() end)
+  else
+    callback()
+  end
+end
+
 return lsp