Move missing methods from page onto frame. (#125)

Closes #113

docs/api.md

@@ -79,13 +79,17 @@
   * [class: Frame](#class-frame)
     + [frame.$(selector, pageFunction, ...args)](#frameselector-pagefunction-args)
     + [frame.$$(selector, pageFunction, ...args)](#frameselector-pagefunction-args)
+    + [frame.addScriptTag(url)](#frameaddscripttagurl)
     + [frame.childFrames()](#framechildframes)
     + [frame.click(selector[, options])](#frameclickselector-options)
     + [frame.evaluate(pageFunction, ...args)](#frameevaluatepagefunction-args)
+    + [frame.focus(selector)](#framefocusselector)
     + [frame.hover(selector)](#framehoverselector)
+    + [frame.injectFile(filePath)](#frameinjectfilefilepath)
     + [frame.isDetached()](#frameisdetached)
     + [frame.name()](#framename)
     + [frame.parentFrame()](#frameparentframe)
+    + [frame.title()](#frametitle)
     + [frame.url()](#frameurl)
     + [frame.waitFor(selectorOrTimeout[, options])](#framewaitforselectorortimeout-options)
     + [frame.waitForSelector(selector[, options])](#framewaitforselectorselector-options)
@@ -347,7 +351,7 @@ Shortcut for [page.mainFrame().$$(selector, pageFunction, ...args)](#pageselecto
 - `url` <[string]> Url of a script to be added
 - returns: <[Promise]> Promise which resolves as the script gets added and loads.
 
-Adds a `<script></script>` tag to the page with the desired url. Alternatively, javascript could be injected to the page via `page.injectFile` method.
+Adds a `<script></script>` tag to the page with the desired url. Alternatively, javascript could be injected to the page via [`page.injectFile`](#pageinjectfilefilepath) method.
 
 #### page.click(selector[, options])
 - `selector` <[string]> A query selector to search for element to click. If there are multiple elements satisfying the selector, the first will be clicked.
@@ -791,6 +795,12 @@ browser.newPage().then(async page => {
 - `...args` <...[string]> Arguments to pass to `pageFunction`
 - returns: <[Promise]<[Array]<[Object]>>> Promise which resolves to array of function return values.
 
+#### frame.addScriptTag(url)
+- `url` <[string]> Url of a script to be added
+- returns: <[Promise]> Promise which resolves as the script gets added and loads.
+
+Adds a `<script></script>` tag to the frame with the desired url. Alternatively, javascript could be injected to the frame via [`frame.injectFile`](#frameinjectfilefilepath) method.
+
 #### frame.childFrames()
 - returns: <[Array]<[Frame]>>
 
@@ -820,10 +830,18 @@ browser.newPage().then(async page =>
 });
 ```
 
+#### frame.focus(selector)
+- `selector` <[string]> A query selector of element to focus. If there are multiple elements satisfying the selector, the first will be focused.
+- returns: <[Promise]> Promise which resolves when the element matching `selector` is successfully focused. Promise gets rejected if there's no element matching `selector`.
+
 #### frame.hover(selector)
 - `selector` <[string]> A query selector to search for element to hover. If there are multiple elements satisfying the selector, the first will be hovered.
 - returns: <[Promise]> Promise which resolves when the element matching `selector` is successfully hovered. Promise gets rejected if there's no element matching `selector`.
 
+#### frame.injectFile(filePath)
+- `filePath` <[string]> Path to the javascript file to be injected into frame.
+- returns: <[Promise]> Promise which resolves when file gets successfully evaluated in frame.
+
 #### frame.isDetached()
 - returns: <[boolean]>
 
@@ -837,6 +855,9 @@ Returns frame's name as specified in the tag.
 #### frame.parentFrame()
 - returns: <[Frame]> Returns parent frame, if any. Detached frames and main frames return `null`.
 
+#### frame.title()
+- returns: <[Promise]<[string]>> Returns page's title.
+
 #### frame.url()
 - returns: <[string]>
 

lib/FrameManager.js

@@ -14,6 +14,7 @@
  * limitations under the License.
  */
 
+let fs = require('fs');
 let EventEmitter = require('events');
 let helper = require('./helper');
 
@@ -157,21 +158,43 @@ class FrameManager extends EventEmitter {
 
   /**
    * @param {!Frame} frame
-   * @param {string} expression
+   * @return {number}
-   * @return {!Promise<(!Object|undefined)>}
    */
-  async _evaluateOnFrame(frame, expression) {
+  _contextIdForFrame(frame) {
     let contextId = undefined;
     if (frame !== this._mainFrame) {
       contextId = this._frameIdToExecutionContextId.get(frame._id);
       console.assert(contextId, 'Frame does not have default context to evaluate in!');
     }
+    return contextId;
+  }
+
+  /**
+   * @param {!Frame} frame
+   * @param {string} expression
+   * @return {!Promise<(!Object|undefined)>}
+   */
+  async _evaluateOnFrame(frame, expression) {
+    let contextId = this._contextIdForFrame(frame);
     expression = `Promise.resolve(${expression})`;
     let { exceptionDetails, result: remoteObject }  = await this._client.send('Runtime.evaluate', { expression, contextId, returnByValue: false, awaitPromise: true });
     if (exceptionDetails)
       throw new Error('Evaluation failed: ' + helper.getExceptionMessage(exceptionDetails));
     return await helper.serializeRemoteObject(this._client, remoteObject);
   }
+
+  /**
+   * @param {!Frame} frame
+   * @param {string} expression
+   * @return {!Promise<(!Object|undefined)>}
+   */
+  async _rawEvaluateOnFrame(frame, expression) {
+    let contextId = this._contextIdForFrame(frame);
+    let { exceptionDetails, result: remoteObject }  = await this._client.send('Runtime.evaluate', { expression, contextId, returnByValue: false });
+    if (exceptionDetails)
+      throw new Error('Evaluation failed: ' + helper.getExceptionMessage(exceptionDetails));
+    return await helper.serializeRemoteObject(this._client, remoteObject);
+  }
 }
 
 /** @enum {string} */
@@ -251,6 +274,40 @@ class Frame {
     return this._detached;
   }
 
+  /**
+   * @param {string} filePath
+   * @return {!Promise}
+   */
+  async injectFile(filePath) {
+    let contents = await new Promise((resolve, reject) => {
+      fs.readFile(filePath, 'utf8', (err, data) => {
+        if (err) return reject(err);
+        resolve(data);
+      });
+    });
+    contents += `//# sourceURL=` + filePath.replace(/\n/g,'');
+    return this._frameManager._rawEvaluateOnFrame(this, contents);
+  }
+
+  /**
+   * @param {string} url
+   * @return {!Promise}
+   */
+  async addScriptTag(url) {
+    return this.evaluate(addScriptTag, url);
+
+    /**
+     * @param {string} url
+     */
+    function addScriptTag(url) {
+      let script = document.createElement('script');
+      script.src = url;
+      let promise = new Promise(x => script.onload = x);
+      document.head.appendChild(script);
+      return promise;
+    }
+  }
+
   /**
    * @param {(string|number)} selectorOrTimeout
    * @param {!Object=} options
@@ -313,6 +370,13 @@ class Frame {
     return this._frameManager._evaluateOnFrame(this, expression);
   }
 
+  /**
+   * @return {!Promise<string>}
+   */
+  async title() {
+    return this.evaluate(() =>  document.title);
+  }
+
   /**
    * @param {string} selector
    * @return {!Promise}
@@ -346,6 +410,22 @@ class Frame {
     await this.evaluate(() => new Promise(f => requestAnimationFrame(f)));
   }
 
+  /**
+   * @param {string} selector
+   * @return {!Promise}
+   */
+  async focus(selector) {
+    let success = await this.evaluate(selector => {
+      let node = document.querySelector(selector);
+      if (!node)
+        return false;
+      node.focus();
+      return true;
+    }, selector);
+    if (!success)
+      throw new Error('No node found for selector: ' + selector);
+  }
+
   /**
    * @param {?Object} framePayload
    */

lib/Page.js

@@ -119,18 +119,7 @@ class Page extends EventEmitter {
    * @return {!Promise}
    */
   async addScriptTag(url) {
-    return this.evaluate(addScriptTag, url);
+    return this.mainFrame().addScriptTag(url);
-
-    /**
-       * @param {string} url
-       */
-    function addScriptTag(url) {
-      let script = document.createElement('script');
-      script.src = url;
-      let promise = new Promise(x => script.onload = x);
-      document.head.appendChild(script);
-      return promise;
-    }
   }
 
   /**
@@ -138,14 +127,7 @@ class Page extends EventEmitter {
    * @return {!Promise}
    */
   async injectFile(filePath) {
-    let contents = await new Promise((resolve, reject) => {
+    return this.mainFrame().injectFile(filePath);
-      fs.readFile(filePath, 'utf8', (err, data) => {
-        if (err) return reject(err);
-        resolve(data);
-      });
-    });
-    contents += `//# sourceURL=` + filePath.replace(/\n/g,'');
-    return this._client.send('Runtime.evaluate', { expression: contents, returnByValue: true });
   }
 
   /**
@@ -498,7 +480,7 @@ class Page extends EventEmitter {
    * @return {!Promise<string>}
    */
   async title() {
-    return this.evaluate(() =>  document.title);
+    return this.mainFrame().title();
   }
 
   /**
@@ -552,15 +534,7 @@ class Page extends EventEmitter {
    * @return {!Promise}
    */
   async focus(selector) {
-    let success = await this.evaluate(selector => {
+    return this.mainFrame().focus(selector);
-      let node = document.querySelector(selector);
-      if (!node)
-        return false;
-      node.focus();
-      return true;
-    }, selector);
-    if (!success)
-      throw new Error('No node found for selector: ' + selector);
   }
 
   /**