Object.defineProperties snippet

bench/snippets/define-properties.mjs

@@ -0,0 +1,145 @@
+import { bench, run } from "../node_modules/mitata/src/cli.mjs";
+
+const properties = {
+  closed: {
+    get() {
+      return this._writableState ? this._writableState.closed : false;
+    },
+  },
+  destroyed: {
+    get() {
+      return this._writableState ? this._writableState.destroyed : false;
+    },
+    set(value) {
+      if (this._writableState) {
+        this._writableState.destroyed = value;
+      }
+    },
+  },
+  writable: {
+    get() {
+      const w = this._writableState;
+      return (
+        !!w &&
+        w.writable !== false &&
+        !w.destroyed &&
+        !w.errored &&
+        !w.ending &&
+        !w.ended
+      );
+    },
+    set(val) {
+      if (this._writableState) {
+        this._writableState.writable = !!val;
+      }
+    },
+  },
+  writableFinished: {
+    get() {
+      return this._writableState ? this._writableState.finished : false;
+    },
+  },
+  writableObjectMode: {
+    get() {
+      return this._writableState ? this._writableState.objectMode : false;
+    },
+  },
+  writableBuffer: {
+    get() {
+      return this._writableState && this._writableState.getBuffer();
+    },
+  },
+  writableEnded: {
+    get() {
+      return this._writableState ? this._writableState.ending : false;
+    },
+  },
+  writableNeedDrain: {
+    get() {
+      const wState = this._writableState;
+      if (!wState) return false;
+      return !wState.destroyed && !wState.ending && wState.needDrain;
+    },
+  },
+  writableHighWaterMark: {
+    get() {
+      return this._writableState && this._writableState.highWaterMark;
+    },
+  },
+  writableCorked: {
+    get() {
+      return this._writableState ? this._writableState.corked : 0;
+    },
+  },
+  writableLength: {
+    get() {
+      return this._writableState && this._writableState.length;
+    },
+  },
+  errored: {
+    enumerable: false,
+    get() {
+      return this._writableState ? this._writableState.errored : null;
+    },
+  },
+  writableAborted: {
+    enumerable: false,
+    get: function () {
+      return !!(
+        this._writableState.writable !== false &&
+        (this._writableState.destroyed || this._writableState.errored) &&
+        !this._writableState.finished
+      );
+    },
+  },
+};
+
+var count = 10_000;
+
+bench("Object.defineProperty x " + count, () => {
+  const prop = {
+    enumerable: false,
+    get: function () {
+      return !!(
+        this._writableState.writable !== false &&
+        (this._writableState.destroyed || this._writableState.errored) &&
+        !this._writableState.finished
+      );
+    },
+  };
+  for (let i = 0; i < count; i++) {
+    function Hey() {
+      return this;
+    }
+    Object.defineProperty(Hey.prototype, "writableAborted", prop);
+  }
+});
+
+bench("Object.defineProperties x " + count, () => {
+  for (let i = 0; i < count; i++) {
+    function Hey() {
+      return this;
+    }
+    Object.defineProperties(Hey.prototype, properties);
+  }
+});
+
+bench("(all the keys) Object.defineProperties x " + count, () => {
+  var first;
+  {
+    function Hey() {
+      return this;
+    }
+    Object.defineProperties(Hey.prototype, properties);
+    first = Object.getOwnPropertyDescriptors(Hey.prototype);
+  }
+
+  for (let i = 0; i < count; i++) {
+    function Hey() {
+      return this;
+    }
+    Object.defineProperties(Hey.prototype, first);
+  }
+});
+
+await run();