fix: another round of type annotation fixes

runtime/lua/vim/diagnostic.lua

@@ -282,6 +282,11 @@ M.severity = {
   [2] = 'WARN',
   [3] = 'INFO',
   [4] = 'HINT',
+  --- Mappings from qflist/loclist error types to severities
+  E = 1,
+  W = 2,
+  I = 3,
+  N = 4,
 }
 
 --- @alias vim.diagnostic.SeverityInt 1|2|3|4
@@ -289,12 +294,6 @@ M.severity = {
 --- See |diagnostic-severity| and |vim.diagnostic.get()|
 --- @alias vim.diagnostic.SeverityFilter vim.diagnostic.Severity|vim.diagnostic.Severity[]|{min:vim.diagnostic.Severity,max:vim.diagnostic.Severity}
 
--- Mappings from qflist/loclist error types to severities
-M.severity.E = M.severity.ERROR
-M.severity.W = M.severity.WARN
-M.severity.I = M.severity.INFO
-M.severity.N = M.severity.HINT
-
 --- @type vim.diagnostic.Opts
 local global_diagnostic_options = {
   signs = true,
@@ -891,14 +890,14 @@ local function next_diagnostic(search_forward, opts)
   if opts.win_id then
     vim.deprecate('opts.win_id', 'opts.winid', '0.13')
     opts.winid = opts.win_id
-    opts.win_id = nil
+    opts.win_id = nil --- @diagnostic disable-line
   end
 
   -- Support deprecated cursor_position alias
   if opts.cursor_position then
     vim.deprecate('opts.cursor_position', 'opts.pos', '0.13')
     opts.pos = opts.cursor_position
-    opts.cursor_position = nil
+    opts.cursor_position = nil --- @diagnostic disable-line
   end
 
   local winid = opts.winid or api.nvim_get_current_win()
@@ -979,7 +978,7 @@ local function goto_diagnostic(diagnostic, opts)
   if opts.win_id then
     vim.deprecate('opts.win_id', 'opts.winid', '0.13')
     opts.winid = opts.win_id
-    opts.win_id = nil
+    opts.win_id = nil --- @diagnostic disable-line
   end
 
   local winid = opts.winid or api.nvim_get_current_win()
@@ -992,8 +991,9 @@ local function goto_diagnostic(diagnostic, opts)
     vim.cmd('normal! zv')
   end)
 
-  if opts.float then
-    local float_opts = type(opts.float) == 'table' and opts.float or {}
+  local float_opts = opts.float
+  if float_opts then
+    float_opts = type(float_opts) == 'table' and float_opts or {}
     vim.schedule(function()
       M.open_float(vim.tbl_extend('keep', float_opts, {
         bufnr = api.nvim_win_get_buf(winid),
@@ -1317,7 +1317,7 @@ function M.jump(opts)
   if opts.cursor_position then
     vim.deprecate('opts.cursor_position', 'opts.pos', '0.13')
     opts.pos = opts.cursor_position
-    opts.cursor_position = nil
+    opts.cursor_position = nil --- @diagnostic disable-line
   end
 
   local diag = nil
@@ -1488,14 +1488,9 @@ M.handlers.underline = {
     local get_priority = severity_to_extmark_priority(vim.hl.priorities.diagnostics, opts)
 
     for _, diagnostic in ipairs(diagnostics) do
-      --- @type string?
+      -- Default to error if we don't have a highlight associated
       local higroup = underline_highlight_map[assert(diagnostic.severity)]
-
-      if higroup == nil then
-        -- Default to error if we don't have a highlight associated
-        -- TODO(lewis6991): this is always nil since underline_highlight_map only has integer keys
-        higroup = underline_highlight_map.Error
-      end
+        or underline_highlight_map[vim.diagnostic.severity.ERROR]
 
       if diagnostic._tags then
         -- TODO(lewis6991): we should be able to stack these.
@@ -2115,9 +2110,10 @@ function M.enable(enable, filter)
 
   enable = enable == nil and true or enable
   local bufnr = filter.bufnr
+  local ns_id = filter.ns_id
 
-  if bufnr == nil then
-    if filter.ns_id == nil then
+  if not bufnr then
+    if not ns_id then
       diagnostic_disabled = (
         enable
           -- Enable everything by setting diagnostic_disabled to an empty table.
@@ -2131,12 +2127,12 @@ function M.enable(enable, filter)
         })
       )
     else
-      local ns = M.get_namespace(filter.ns_id)
+      local ns = M.get_namespace(ns_id)
       ns.disabled = not enable
     end
   else
     bufnr = get_bufnr(bufnr)
-    if filter.ns_id == nil then
+    if not ns_id then
       diagnostic_disabled[bufnr] = (not enable) and true or nil
     else
       if type(diagnostic_disabled[bufnr]) ~= 'table' then
@@ -2146,14 +2142,14 @@ function M.enable(enable, filter)
           diagnostic_disabled[bufnr] = {}
         end
       end
-      diagnostic_disabled[bufnr][filter.ns_id] = (not enable) and true or nil
+      diagnostic_disabled[bufnr][ns_id] = (not enable) and true or nil
     end
   end
 
   if enable then
-    M.show(filter.ns_id, bufnr)
+    M.show(ns_id, bufnr)
   else
-    M.hide(filter.ns_id, bufnr)
+    M.hide(ns_id, bufnr)
   end
 end