From 76313263b6196ccb23331cd51fc0c12a8acc7633 Mon Sep 17 00:00:00 2001
From: Wolfgang Popp <mail@wolfgang-popp.de>
Date: Tue, 26 Apr 2016 22:14:09 +0200
Subject: [PATCH] Add clear() function to awful.widget.graph and doc fixes
 (#847)

* awful.widget.graph: add clear() function.

* awful.widget.graph: doc fixes for add_value.
add_value did not show up in generated luadoc. And the value parameter does not need to be between 0 and 1.

* awful.widget.graph: local functions clear and add_value as methods of graph.
---
 lib/awful/widget/graph.lua | 41 +++++++++++++++++++++-----------------
 1 file changed, 23 insertions(+), 18 deletions(-)

diff --git a/lib/awful/widget/graph.lua b/lib/awful/widget/graph.lua
index 782d8cfa..828a0509 100644
--- a/lib/awful/widget/graph.lua
+++ b/lib/awful/widget/graph.lua
@@ -161,42 +161,46 @@ function graph.fit(_graph)
 end
 
 --- Add a value to the graph
--- @param _graph The graph.
--- @param value The value between 0 and 1.
+--
+-- @param value The value to be added to the graph
 -- @param group The stack color group index.
-local function add_value(_graph, value, group)
-    if not _graph then return end
-
+function graph:add_value(value, group)
     value = value or 0
-    local values = _graph._data.values
-    local max_value = _graph._data.max_value
+    local values = self._data.values
+    local max_value = self._data.max_value
     value = math.max(0, value)
-    if not _graph._data.scale then
+    if not self._data.scale then
         value = math.min(max_value, value)
     end
 
-    if _graph._data.stack and group then
-        if not  _graph._data.values[group]
-        or type(_graph._data.values[group]) ~= "table"
+    if self._data.stack and group then
+        if not  self._data.values[group]
+        or type(self._data.values[group]) ~= "table"
         then
-            _graph._data.values[group] = {}
+            self._data.values[group] = {}
         end
-        values = _graph._data.values[group]
+        values = self._data.values[group]
     end
     table.insert(values, value)
 
     local border_width = 0
-    if _graph._data.border_color then border_width = 2 end
+    if self._data.border_color then border_width = 2 end
 
     -- Ensure we never have more data than we can draw
-    while #values > _graph._data.width - border_width do
+    while #values > self._data.width - border_width do
         table.remove(values, 1)
     end
 
-    _graph:emit_signal("widget::redraw_needed")
-    return _graph
+    self:emit_signal("widget::redraw_needed")
+    return self
 end
 
+--- Clear the graph.
+function graph:clear()
+    self._data.values = {}
+    self:emit_signal("widget::redraw_needed")
+    return self
+end
 
 --- Set the graph height.
 -- @param height The height to set.
@@ -253,7 +257,8 @@ function graph.new(args)
     _graph._data = { width = width, height = height, values = {}, max_value = 1 }
 
     -- Set methods
-    _graph.add_value = add_value
+    _graph.add_value = graph["add_value"]
+    _graph.clear = graph["clear"]
     _graph.draw = graph.draw
     _graph.fit = graph.fit