root: Turn `root.keys()` into a property.

lib/awful/_compat.lua

@@ -70,3 +70,11 @@ gprop._legacy_accessors(capi.root, "buttons", "_buttons", false, function(new_bt
         type(new_btns[1]) == "button" or new_btns[1]._is_capi_button
     ) or false
 end, true)
+
+gprop._legacy_accessors(capi.root, "keys", "_keys", false, function(new_btns)
+    return new_btns[1] and (
+        type(new_btns[1]) == "key" or new_btns[1]._is_capi_button
+    ) or false
+end, true)
+
+assert(root.keys)

root.c

@@ -335,11 +335,12 @@ luaA_root_fake_input(lua_State *L)
 }
 
 /** Get or set global key bindings.
- * These bindings will be available when you press keys on the root window.
+ * These bindings will be available when you press keys on the root window
+ * (the wallpaper).
  *
- * @tparam table|nil keys_array An array of key binding objects, or nothing.
- * @return The array of key bindings objects of this client.
- * @staticfct keys
+ * @property keys
+ * @param table
+ * @see awful.key
  */
 static int
 luaA_root_keys(lua_State *L)
@@ -597,7 +598,7 @@ luaA_root_newindex(lua_State *L)
 const struct luaL_Reg awesome_root_methods[] =
 {
     { "_buttons", luaA_root_buttons },
-    { "keys", luaA_root_keys },
+    { "_keys", luaA_root_keys },
     { "cursor", luaA_root_cursor },
     { "fake_input", luaA_root_fake_input },
     { "drawins", luaA_root_drawins },

tests/examples/shims/root.lua

@@ -32,7 +32,7 @@ function root.cursor() end
 
 local keys = {}
 
-function root.keys(k)
+function root._keys(k)
     keys = k or keys
     return keys
 end