Add benchmarks for selectors

bench/benchSelectors.js

@@ -0,0 +1,40 @@
+
+import Stylesheet from '../src/stylesheet'
+import Node from '../src/node'
+import { parseSelector } from '../src/selectors'
+
+const s = new Stylesheet()
+
+const appNode = new Node('App', {}, undefined, s)
+const appViewNode = new Node('AppView', {}, appNode, s)
+const elemNode = new Node('Elem', {variant: ['selected']}, appViewNode, s)
+const itemNode = new Node('Item', {}, elemNode, s)
+const textNode = new Node('Text', {prop1: 1}, itemNode, s)
+
+function createBenchFunc (sel, node, expected) {
+  return function () {
+    const actual = sel.matchContext(node)
+    if (actual !== expected) {
+      throw new Error(`expected ${expected} but got ${actual}`)
+    }
+  }
+}
+
+export default [
+  {
+    name: 'selectors: simple match',
+    fn: createBenchFunc(parseSelector('Text'), textNode, true)
+  },
+  {
+    name: 'selectors: simple not match',
+    fn: createBenchFunc(parseSelector('NotExists'), textNode, false)
+  },
+  {
+    name: 'selectors: complex match',
+    fn: createBenchFunc(parseSelector('AppView Elem.selected Text'), textNode, true)
+  },
+  {
+    name: 'selectors: complex not match',
+    fn: createBenchFunc(parseSelector('NotExists Elem Text'), textNode, false)
+  }
+]

bench/index.js

@@ -2,9 +2,14 @@
 import Benchmark from 'benchmark'
 
 import benchStylesheet from './benchStylesheet'
+import selectorsBenchmarks from './benchSelectors'
 
 const suite = new Benchmark.Suite()
 
+for (let i = 0; i < selectorsBenchmarks.length; ++i) {
+  suite.add(selectorsBenchmarks[i])
+}
+
 suite.add('Stylesheet#getProps', benchStylesheet)
 
 suite.on('cycle', function (e) {