内置 flru 避免打包问题 (#111)

* fix: move flru to codebase #110

* chore: bump version

package.json

@@ -1,6 +1,6 @@
 {
   "name": "@antv/util",
-  "version": "3.3.5",
+  "version": "3.3.6",
   "license": "MIT",
   "sideEffects": false,
   "main": "lib/index.js",
@@ -90,7 +90,6 @@
   },
   "dependencies": {
     "fast-deep-equal": "^3.1.3",
-    "flru": "^1.0.2",
     "gl-matrix": "^3.3.0",
     "tslib": "^2.3.1"
   },

src/lodash/memoize.ts

@@ -1,6 +1,49 @@
-import flru from 'flru';
 import isFunction from './is-function';
 
+function flru(max: number) {
+  let num, curr, prev;
+  const limit = max || 1;
+
+  function keep(key, value) {
+    if (++num > limit) {
+      prev = curr;
+      reset(1);
+      ++num;
+    }
+    curr[key] = value;
+  }
+
+  function reset(isPartial?: number) {
+    num = 0;
+    curr = Object.create(null);
+    isPartial || (prev = Object.create(null));
+  }
+
+  reset();
+
+  return {
+    clear: reset,
+    has: function (key) {
+      return curr[key] !== void 0 || prev[key] !== void 0;
+    },
+    get: function (key) {
+      var val = curr[key];
+      if (val !== void 0) return val;
+      if ((val = prev[key]) !== void 0) {
+        keep(key, val);
+        return val;
+      }
+    },
+    set: function (key, value) {
+      if (curr[key] !== void 0) {
+        curr[key] = value;
+      } else {
+        keep(key, value);
+      }
+    },
+  };
+}
+
 /**
  * _.memoize(calColor);
  * _.memoize(calColor, (...args) => args[0]);