From 6c7ae41ae6b85fe228818b5187b3bbea1f78d6d2 Mon Sep 17 00:00:00 2001
From: Paul Irish <paul.irish@gmail.com>
Date: Thu, 6 Jul 2017 16:09:23 -0700
Subject: [PATCH] fix page.injectFile and add test. (#52)

This line within `injectFile` wasn't doing much of anything:

```js
let expression = fs.readFile(filePath, 'utf8', (err, data) => callback({err, data}));
```

* That's fixed.
* A path error in examples/features.js is fixed.
* Test added for injectFile.
---
 examples/features.js        |  2 +-
 lib/Page.js                 | 12 +++++++-----
 test/assets/injectedfile.js |  1 +
 test/test.js                |  9 +++++++++
 4 files changed, 18 insertions(+), 6 deletions(-)
 create mode 100644 test/assets/injectedfile.js

diff --git a/examples/features.js b/examples/features.js
index 7e4d277a71c..6c28f811560 100644
--- a/examples/features.js
+++ b/examples/features.js
@@ -19,7 +19,7 @@ var Browser = require('../lib/Browser');
 var browser = new Browser();
 
 browser.newPage().then(async page => {
-    var modernizrPath = path.join('..', 'third_party', 'phantomjs', 'examples', 'modernizr.js');
+    var modernizrPath = path.join(__dirname, '../third_party/phantomjs/examples/modernizr.js');
     await page.injectFile(modernizrPath);
     page.on('consolemessage', console.log);
     await page.evaluate(detectFeatures);
diff --git a/lib/Page.js b/lib/Page.js
index 51b12074993..ae4877e8371 100644
--- a/lib/Page.js
+++ b/lib/Page.js
@@ -128,11 +128,13 @@ class Page extends EventEmitter {
    * @return {!Promise}
    */
   async injectFile(filePath) {
-    let callback;
-    let promise = new Promise(fulfill => callback = fulfill);
-    let expression = fs.readFile(filePath, 'utf8', (err, data) => callback({err, data}));
-    await promise;
-    return this._client.send('Runtime.evaluate', { expression, returnByValue: true });
+    const contents = await new Promise((resolve, reject) => {
+      fs.readFile(filePath, 'utf8', (err, data) => {
+        if (err) return reject(err);
+        resolve(data);
+      });
+    });
+    return this._client.send('Runtime.evaluate', { expression: contents, returnByValue: true });
   }
 
   /**
diff --git a/test/assets/injectedfile.js b/test/assets/injectedfile.js
new file mode 100644
index 00000000000..57b4464fcdd
--- /dev/null
+++ b/test/assets/injectedfile.js
@@ -0,0 +1 @@
+__injected = 42;
diff --git a/test/test.js b/test/test.js
index ed5f25d9083..2448543157b 100644
--- a/test/test.js
+++ b/test/test.js
@@ -104,6 +104,15 @@ describe('Puppeteer', function() {
     }));
   });
 
+  describe('Page.injectFile', function() {
+    it('should fail when navigating to bad url', SX(async function() {
+      const helloPath = path.join(__dirname, './assets/injectedfile.js');
+      await page.injectFile(helloPath);
+      const result = await page.evaluate(() => __injected);
+      expect(result).toBe(42);
+    }));
+  });
+
   describe('Frame.evaluate', function() {
     let FrameUtils = require('./frame-utils');
     it('should have different execution contexts', SX(async function() {