Add benchmark for very large buffers

benchmark/large-text-buffer.benchmark.js

@@ -0,0 +1,56 @@
+const http = require('http')
+const fs = require('fs')
+const unzip = require('unzip')
+const { TextBuffer } = require('..')
+
+const unzipper = unzip.Parse()
+
+const getText = () => {
+  return new Promise(resolve => {
+    console.log('fetching text file...')
+    const req = http.get({
+      hostname: 'www.acleddata.com',
+      port: 80,
+      // 51 MB text file
+      path: '/wp-content/uploads/2017/01/ACLED-Version-7-All-Africa-1997-2016_csv_dyadic-file.zip',
+      agent: false
+    }, res => {
+      res
+        .pipe(unzipper)
+        .on('entry', entry => {
+          let data = '';
+          entry.on('data', chunk => data += chunk);
+          entry.on('end', () => {
+            resolve(data)
+          });
+        })
+    })
+
+    req.end()
+  })
+}
+
+const timer = size => `Time to find "cat" in ${size} file`
+
+getText().then(txt => {
+  const buffer = new TextBuffer()
+
+  console.log('running findWordsWithSubsequence tests...')
+
+  const sizes = [['10b', 10], ['100b', 100], ['1kb', 1000], ['1MB', 1000000], ['51MB', 100000000]]
+
+  const test = size => {
+    const _timer = timer(size[0])
+    buffer.setText(txt.slice(0, size[1]))
+    console.time(_timer)
+    return buffer.findWordsWithSubsequence('cat', '', 100).then(sugs => {
+      console.timeEnd(_timer)
+    })
+  }
+
+  return sizes.reduce((promise, size) => {
+    return promise.then(() => test(size))
+  }, Promise.resolve())
+}).then(() => {
+  console.log('finished')
+})

package.json

@@ -40,7 +40,8 @@
     "random-seed": "^0.2.0",
     "stackvis": "^0.4.0",
     "standard": "^4.5.4",
-    "temp": "^0.8.3"
+    "temp": "^0.8.3",
+    "unzip": "^0.1.11"
   },
   "standard": {
     "global": [