Merge pull request #5 from GitbookIO/memoization-global-disabler

Global memoization control, faster benchmark script

perf/index.js

@@ -20,6 +20,8 @@ const fs = require('fs')
 const _ = require('lodash')
 const readMetadata = require('read-metadata')
 const { Raw } = require('..')
+const memoize = require('../lib/utils/memoize')
+
 const { resolve } = require('path')
 
 const DEFAULT_BENCHMARK = {
@@ -75,6 +77,7 @@ function runBenchmarks() {
     // Setup global scope for this benchmark
     global.setScope(benchmarkName, {
       Raw,
+      memoize,
       benchmark,
       input
     })
@@ -91,31 +94,25 @@ function runBenchmarks() {
 
       // Time spent in setup is not taken into account
       setup() {
-        // Create as much independant Slate.State as needed, to avoid
-        // memoization between calls to `fn`
         const scope = global.getScope()
-
+        // Each benchmark is given the chance to do its own setup
-        let states = []
+        const state = scope.benchmark.setup(
-        let numberOfExecution = this.count
+          scope.Raw.deserialize(scope.input, { terse: true })
-        while (numberOfExecution--) {
+        )
-          states.push(
-            // Each benchmark is given the chance to do its own setup
-            scope.benchmark.setup(
-              scope.Raw.deserialize(scope.input, { terse: true })
-            )
-          )
-        }
-
-        let stateIndex = 0
       },
 
       // Because of the way BenchmarkJS compiles the functions,
       // the variables declared in `setup` are visible to `fn`
 
       fn() {
-        scope.benchmark.run(states[stateIndex]) // eslint-disable-line no-undef
+        scope.benchmark.run(state) // eslint-disable-line no-undef
-        // Next call will use another State instance
+        // Clear memoized values between each run
-        stateIndex++ // eslint-disable-line no-undef
+        scope.memoize.__clear() // eslint-disable-line no-undef
+      },
+
+      onComplete() {
+        const teardown = global.getScope().benchmark.teardown
+        if (teardown) teardown()
       }
     }))
   }

src/utils/memoize.js

@@ -1,5 +1,18 @@
 /* global Map */
 
+import IS_DEV from './is-dev'
+
+/**
+ * This module serves to memoize methods on immutable instances.
+ */
+
+// Global: True if memoization should is enabled. Only effective in DEV mode
+let ENABLED = true
+
+// Global: Changing this cache key will clear all previous cached
+// results. Only effective in DEV mode
+let CACHE_KEY = 0
+
 /**
  * The leaf node of a cache tree. Used to support variable argument length.
  *
@@ -42,6 +55,17 @@ function memoize(object, properties) {
     }
 
     object[property] = function (...args) {
+      if (IS_DEV) {
+        if (!ENABLED) {
+          // Memoization disabled
+          return original.apply(this, args)
+        } else if (CACHE_KEY !== this.__cache_key) {
+          // Previous caches must be cleared
+          this.__cache_key = CACHE_KEY
+          this.__cache = new Map()
+        }
+      }
+
       const keys = [property, ...args]
       this.__cache = this.__cache || new Map()
 
@@ -114,8 +138,34 @@ function getIn(map, keys) {
   return childMap.get(LEAF)
 }
 
+/**
+ * In DEV mode, clears the previously memoized values, globally.
+ * @return {Void}
+ */
+
+function __clear() {
+  CACHE_KEY++
+  if (CACHE_KEY >= Number.MAX_SAFE_INTEGER) {
+    CACHE_KEY = 0
+  }
+}
+
+/**
+ * In DEV mode, enable or disable the use of memoize values, globally.
+ * @param {Boolean} enabled
+ * @return {Void}
+ */
+
+function __enable(enabled) {
+  ENABLED = enabled
+}
+
 /**
  * Export.
  */
 
-export default memoize
+export {
+  memoize as default,
+  __clear,
+  __enable
+}