From a239b2cac792fc89d72cbff9e6a7bfa8d890adcf Mon Sep 17 00:00:00 2001
From: Uli Schlachter <psychon@znc.in>
Date: Sat, 13 Jun 2015 16:55:10 +0200
Subject: [PATCH] Use gears.cache to replace some other caches

Signed-off-by: Uli Schlachter <psychon@znc.in>
---
 lib/gears/color.lua       | 12 ++++--------
 lib/wibox/layout/base.lua | 16 +---------------
 lib/wibox/widget/base.lua |  8 ++++++--
 spec/wibox/test_utils.lua |  3 ++-
 4 files changed, 13 insertions(+), 26 deletions(-)

diff --git a/lib/gears/color.lua b/lib/gears/color.lua
index 63b0e0158..376177df0 100644
--- a/lib/gears/color.lua
+++ b/lib/gears/color.lua
@@ -17,7 +17,7 @@ local cairo = require("lgi").cairo
 local surface = require("gears.surface")
 
 local color = { mt = {} }
-local pattern_cache = setmetatable({}, { __mode = 'v' })
+local pattern_cache
 
 --- Parse a HTML-color.
 -- This function can parse colors like `#rrggbb` and `#rrggbbaa`.
@@ -231,13 +231,7 @@ function color.create_pattern(col)
     if cairo.Pattern:is_type_of(col) then
         return col
     end
-    local col = col or "#000000"
-    local result = pattern_cache[col]
-    if not result then
-        result = color.create_pattern_uncached(col)
-        pattern_cache[col] = result
-    end
-    return result
+    return pattern_cache:get(col or "#000000")
 end
 
 --- Check if a pattern is opaque.
@@ -296,6 +290,8 @@ function color.mt:__call(...)
     return color.create_pattern(...)
 end
 
+pattern_cache = require("gears.cache").new(color.create_pattern_uncached)
+
 return setmetatable(color, color.mt)
 
 -- vim: filetype=lua:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:textwidth=80
diff --git a/lib/wibox/layout/base.lua b/lib/wibox/layout/base.lua
index 1c5b8b83f..1a9331bc3 100644
--- a/lib/wibox/layout/base.lua
+++ b/lib/wibox/layout/base.lua
@@ -38,21 +38,7 @@ function base.fit_widget(widget, width, height)
     local width = math.max(0, width)
     local height = math.max(0, height)
 
-    -- Since the geometry cache is a weak table, we have to be careful when
-    -- doing lookups. We can't do "if cache[width] ~= nil then"!
-    local cache = widget._fit_geometry_cache
-    local result = cache[width]
-    if not result then
-        result = {}
-        cache[width] = result
-    end
-    cache, result = result, result[height]
-    if not result then
-        local w, h = widget:fit(width, height)
-        result = { width = w, height = h }
-        cache[height] = result
-    end
-    return result.width, result.height
+    return widget._fit_geometry_cache:get(width, height)
 end
 
 --- Draw a widget via a cairo context
diff --git a/lib/wibox/widget/base.lua b/lib/wibox/widget/base.lua
index ca24c46fd..e001b02f5 100644
--- a/lib/wibox/widget/base.lua
+++ b/lib/wibox/widget/base.lua
@@ -7,6 +7,7 @@
 
 local debug = require("gears.debug")
 local object = require("gears.object")
+local cache = require("gears.cache")
 local setmetatable = setmetatable
 local pairs = pairs
 local type = type
@@ -96,9 +97,12 @@ function base.make_widget(proxy)
     end
 
     -- Add a geometry for base.fit_widget() that is cleared when necessary
-    ret._fit_geometry_cache = setmetatable({}, { __mode = 'v' })
+    local function cb(...)
+        return ret:fit(...)
+    end
+    ret._fit_geometry_cache = cache.new(cb)
     ret:connect_signal("widget::updated", function()
-        ret._fit_geometry_cache = setmetatable({}, { __mode = 'v' })
+        ret._fit_geometry_cache = cache.new(cb)
     end)
 
     return ret
diff --git a/spec/wibox/test_utils.lua b/spec/wibox/test_utils.lua
index 180de905f..c3ccbd2d2 100644
--- a/spec/wibox/test_utils.lua
+++ b/spec/wibox/test_utils.lua
@@ -4,6 +4,7 @@
 ---------------------------------------------------------------------------
 
 local object = require("gears.object")
+local cache = require("gears.cache")
 local wbase = require("wibox.widget.base")
 local lbase = require("wibox.layout.base")
 local say = require("say")
@@ -64,7 +65,7 @@ return {
             return width or 10, height or 10
         end
         w.draw = function() end
-        w._fit_geometry_cache = {}
+        w._fit_geometry_cache = cache.new(w.fit)
 
         spy.on(w, "fit")
         stub(w, "draw")