`gui.set_theme()` accepts key-value argument pairs for theme properties to set.

2 files changed, 22 insertions, 9 deletions

diff --git a/core/gui.lua b/core/gui.lua
index c8e593f2..bee5c567 100644
--- a/core/gui.lua
+++ b/core/gui.lua
@@ -164,14 +164,17 @@ end
 ---
 -- Sets the editor theme name to *name* or prompts the user to select one from a
 -- list of themes found in the *`_USERHOME`/themes/* and *`_HOME`/themes/*
--- directories.
+-- directories and optionally sets key-value pair argument properties.
 -- User themes override Textadept's default themes when they have the same name.
 -- If *name* contains slashes, it is assumed to be an absolute path to a theme
 -- instead of a theme name.
 -- @param name Optional name or absolute path of a theme to set. If `nil`, the
 --   user is prompted for one.
+-- @param ... key-value argument pairs for theme properties to set. These
+--   override the theme's defaults.
+-- @usage gui.set_theme('light', 'font', 'Monospace', 'fontsize', 12)
 -- @name set_theme
-function gui.set_theme(name)
+function gui.set_theme(name, ...)
   if not name then
     local themes, themes_found = {}, {}
     for theme in lfs.dir(_HOME..'/themes') do
@@ -193,15 +196,18 @@ function gui.set_theme(name)
                                     _HOME..'/themes/?.lua')
   end
   if not name or not lfs.attributes(name) then return end
+  local buffer, props = buffer, {...}
   local current_buffer, current_view = _BUFFERS[buffer], _VIEWS[view]
   for i = 1, #_BUFFERS do
     view:goto_buffer(i)
     dofile(name)
+    for j = 1, #props, 2 do buffer.property[props[j]] = props[j + 1] end
   end
   view:goto_buffer(current_buffer)
   for i = 1, #_VIEWS do
     gui.goto_view(i)
     dofile(name)
+    for j = 1, #props, 2 do buffer.property[props[j]] = props[j + 1] end
   end
   gui.goto_view(current_view)
 --  if not RESETTING then reset() end
diff --git a/doc/09_Themes.md b/doc/09_Themes.md
index b98d763c..ccdbf85e 100644
--- a/doc/09_Themes.md
+++ b/doc/09_Themes.md
@@ -49,17 +49,24 @@ There are two ways to go about customizing themes. You can create a new one from
 scratch or tweak an existing one. Creating a new one is straightforward -- all
 you need to do is define a set of colors and a set of styles. Just follow the
 example of existing themes. If instead you want to use an existing theme like
-"light" but only change the font face and font size, you do not have to copy the
-whole theme to your *~/.textadept/themes/light.lua* before changing the font
-settings. Tweaking themes is very simple with Lua's `dofile()` function. In your
-*~/.textadept/themes/light.lua*, put:
+"light" but only change the font face and font size, you have two options: call
+[`gui.set_theme()`][] with additional parameters from your
+*~/.textadept/init.lua* or create an abbreviated *~/.textadept/themes/light.lua*
+using Lua's `dofile()` function. For example:
 
+    -- File *~/.textadept/init.lua*
+    gui.set_theme('light', 'font', 'Monospace', 'fontsize', 12)
+
+    -- File *~/.textadept/themes/light.lua*
     dofile(_HOME..'/themes/light.lua')
-    buffer.property['font'] = 'font face'
+    buffer.property['font'] = 'Monospace'
     buffer.property['fontsize'] = size
 
-This loads Textadept's "light" theme, but applies your font preferences. The
-same technique works for tweaking individual theme colors and/or styles.
+Either one loads Textadept's "light" theme, but applies your font preferences.
+The same techniques work for tweaking individual theme colors and/or styles, but
+managing more changes is probably easier with the latter.
+
+[`gui.set_theme()`]: api/gui.html#set_theme
 
 ### Language-Specific