Implement profiler

lib/profiler.lua

@@ -0,0 +1,35 @@
+local thing = _G._PUBLIC or _G
+thing.__PROFILER_INSTANCE = thing.__PROFILER_INSTANCE or { timers = {} }
+local timers = thing.__PROFILER_INSTANCE.timers
+local profiler = {}
+
+function profiler.start(label, overwrite)
+  thing.__PROFILER_INSTANCE.lastadded = label
+  timers[label] = timers[label] or {}
+  if not timers[label].start or overwrite then
+    timers[label].start = os.clock()
+  end
+  return function() timers[label].time = timers[label].time or os.clock() - timers[label].start end
+end
+
+function profiler.results()
+  local _now = nil
+  local function now()
+    _now = _now or os.clock()
+    return _now
+  end
+  local out = {}
+  for label, t in pairs(timers) do
+    table.insert(out, { label = label, time = t.time or now() - t.start })
+  end
+  table.sort(out, function(a, b) return a.time > b.time end)
+  return out
+end
+
+function profiler.profile(label, func, ...)
+  local stop = profiler.start(label)
+  func(...)
+  stop()
+end
+
+return profiler