leak test: Make the layoutbox test pass

This commit does two things: It gets rid of the reference to the layoutbox that
the default config created and it changes the widget dependency cache to not
keep widgets alive unnecessarily.

Signed-off-by: Uli Schlachter <psychon@znc.in>

lib/wibox/widget/base.lua

@@ -18,7 +18,7 @@ local base = {}
 -- {{{ Caches
 
 -- Indexes are widgets, allow them to be garbage-collected
-local widget_dependencies = setmetatable({}, { __mode = "k" })
+local widget_dependencies = setmetatable({}, { __mode = "kv" })
 
 -- Get the cache of the given kind for this widget. This returns a gears.cache
 -- that calls the callback of kind `kind` on the widget.

tests/test-leaks.lua

@@ -10,6 +10,12 @@ local errors = {}
 
 local prepare_for_collect = nil
 
+-- Make the layoutbox in the default config GC'able
+mywibox[1].visible = false
+mywibox = nil
+mylayoutbox = nil
+awesome.emit_signal("refresh")
+
 -- Test if some objects can be garbage collected
 local function collectable(a, b, c, d, e, f, g, h, last)
     assert(last == nil, "got more arguments than supported")