Merge #38833

runtime/doc/lua.txt

@@ -2409,6 +2409,20 @@ vim.filetype.get_option({filetype}, {option})
     Return: ~
         (`string|boolean|integer`) Option value
 
+vim.filetype.inspect()                                *vim.filetype.inspect()*
+    Inspect the current state of the filetype registry.
+
+    Returns a copy of the internal tables used for filetype detection by
+    extension, filename, or pattern. Note: Due to the dynamic nature of
+    filetype detection, this is only useful for checking whether a certain
+    extension, filename, or pattern has been registered so far. In addition,
+    the `pattern` table is in an internal format optimized for fast lookup.
+    Prefer |vim.filetype.match()| for checking the detected filetype for a
+    given pattern.
+
+    Return: ~
+        (`table<string, table<string, vim.filetype.mapping|table<string, vim.filetype.mapping>>>`)
+
 vim.filetype.match({args})                              *vim.filetype.match()*
     Perform filetype detection.
 

runtime/doc/news.txt

@@ -299,6 +299,8 @@ LUA
 • |vim.json.encode()| `sort_keys` option sorts by key.
 • |vim.json.decode()| `skip_comments` option allows comments in JSON data.
 • EXPERIMENTAL: |vim.pos|, |vim.range| provide Position/Range abstraction.
+• |vim.filetype.inspect()| returns a copy of the internal tables used for
+  filetype detection.
 
 OPTIONS
 
@@ -394,6 +396,8 @@ TUI
   sequence.
 • The TUI now renders the SGR dim (faint), blink, conceal, and overline
   attributes.
+• The TUI will re-query the terminal's background color when resuming from
+  a suspended state, and Nvim will update 'background' accordingly.
 
 UI
 

runtime/lua/vim/filetype.lua

@@ -3295,4 +3295,20 @@ function M.get_option(filetype, option)
   return require('vim.filetype.options').get_option(filetype, option)
 end
 
+--- Inspect the current state of the filetype registry.
+---
+--- Returns a copy of the internal tables used for filetype detection by extension, filename, or
+--- pattern. Note: Due to the dynamic nature of filetype detection, this is only useful for checking
+--- whether a certain extension, filename, or pattern has been registered so far. In addition, the
+--- `pattern` table is in an internal format optimized for fast lookup. Prefer |vim.filetype.match()|
+--- for checking the detected filetype for a given pattern.
+---@return table<string, table<string, vim.filetype.mapping|table<string, vim.filetype.mapping>>>
+function M.inspect()
+  return {
+    extension = vim.deepcopy(extension),
+    filename = vim.deepcopy(filename),
+    pattern = vim.deepcopy(pattern),
+  }
+end
+
 return M

src/nvim/tui/tui.c

@@ -337,14 +337,20 @@ static void tui_reset_key_encoding(TUIData *tui)
   }
 }
 
+static void tui_query_bg_color_noflush(TUIData *tui)
+  FUNC_ATTR_NONNULL_ALL
+{
+  out(tui, S_LEN("\x1b]11;?\x07\x1b[5n"));
+}
+
 /// Write the OSC 11 + DSR sequence to the terminal emulator to query the current
-/// background color.
+/// background color, and flush the terminal.
 ///
 /// Response will be handled by the TermResponse handler in _core/defaults.lua.
 void tui_query_bg_color(TUIData *tui)
   FUNC_ATTR_NONNULL_ALL
 {
-  out(tui, S_LEN("\x1b]11;?\x07\x1b[5n"));
+  tui_query_bg_color_noflush(tui);
   flush_buf(tui);
 }
 
@@ -483,6 +489,11 @@ static void terminfo_start(TUIData *tui)
   // Query the terminal to see if it supports Kitty's keyboard protocol
   tui_query_kitty_keyboard(tui);
 
+  // Query the terminal's background color. We normally get it via continuous reporting (set via
+  // `kTermModeThemeUpdates` above), but if we were backgrounded while the light/dark mode changed,
+  // we won't have received the report, so we also query it on resume.
+  tui_query_bg_color_noflush(tui);
+
   int ret;
   uv_loop_init(&tui->write_loop);
   if (tui->out_isatty) {