1 files changed, 24 insertions, 15 deletions
diff --git a/runtime/lua/vim/diagnostic.lua b/runtime/lua/vim/diagnostic.lua
index 00945a7fb3..c7c8c1878e 100644
--- a/runtime/lua/vim/diagnostic.lua
+++ b/runtime/lua/vim/diagnostic.lua
@@ -556,6 +556,9 @@ end
 ---       - signs: (default true) Use signs for diagnostics. Options:
 ---                * severity: Only show signs for diagnostics matching the given severity
 ---                |diagnostic-severity|
+---                * priority: (number, default 10) Base priority to use for signs. When
+---                {severity_sort} is used, the priority of a sign is adjusted based on
+---                its severity. Otherwise, all signs use the same priority.
 ---       - update_in_insert: (default false) Update diagnostics in Insert mode (if false,
 ---                           diagnostics are updated on InsertLeave)
 ---       - severity_sort: (default false) Sort diagnostics by severity. This affects the order in
@@ -617,23 +620,22 @@ function M.set(namespace, bufnr, diagnostics, opts)
   }
 
   if vim.tbl_isempty(diagnostics) then
-    return M.reset(namespace, bufnr)
-  end
-
-  if not diagnostic_cleanup[bufnr][namespace] then
-    diagnostic_cleanup[bufnr][namespace] = true
-
-    -- Clean up our data when the buffer unloads.
-    vim.api.nvim_buf_attach(bufnr, false, {
-      on_detach = function(_, b)
-        clear_diagnostic_cache(b, namespace)
-        diagnostic_cleanup[b][namespace] = nil
-      end
-    })
+    clear_diagnostic_cache(namespace, bufnr)
+  else
+    if not diagnostic_cleanup[bufnr][namespace] then
+      diagnostic_cleanup[bufnr][namespace] = true
+
+      -- Clean up our data when the buffer unloads.
+      vim.api.nvim_buf_attach(bufnr, false, {
+        on_detach = function(_, b)
+          clear_diagnostic_cache(b, namespace)
+          diagnostic_cleanup[b][namespace] = nil
+        end
+      })
+    end
+    set_diagnostic_cache(namespace, bufnr, diagnostics)
   end
 
-  set_diagnostic_cache(namespace, bufnr, diagnostics)
-
   if vim.api.nvim_buf_is_loaded(bufnr) then
     M.show(namespace, bufnr, diagnostics, opts)
   elseif opts then
@@ -643,6 +645,13 @@ function M.set(namespace, bufnr, diagnostics, opts)
   vim.api.nvim_command("doautocmd <nomodeline> User DiagnosticsChanged")
 end
 
+--- Get current diagnostic namespaces.
+---
+---@return table A list of active diagnostic namespaces |vim.diagnostic|.
+function M.get_namespaces()
+  return vim.deepcopy(all_namespaces)
+end
+
 --- Get current diagnostics.
 ---
 ---@param bufnr number|nil Buffer number to get diagnostics from. Use 0 for