feat(page): Introduce page.setGeolocation method (#3160)

Fixes #1077

docs/api.md

@@ -118,6 +118,7 @@ Next Release: **Sep 6, 2018**
   * [page.setCookie(...cookies)](#pagesetcookiecookies)
   * [page.setDefaultNavigationTimeout(timeout)](#pagesetdefaultnavigationtimeouttimeout)
   * [page.setExtraHTTPHeaders(headers)](#pagesetextrahttpheadersheaders)
+  * [page.setGeolocation(options)](#pagesetgeolocationoptions)
   * [page.setJavaScriptEnabled(enabled)](#pagesetjavascriptenabledenabled)
   * [page.setOfflineMode(enabled)](#pagesetofflinemodeenabled)
   * [page.setRequestInterception(value)](#pagesetrequestinterceptionvalue)
@@ -1556,6 +1557,21 @@ The extra HTTP headers will be sent with every request the page initiates.
 
 > **NOTE** page.setExtraHTTPHeaders does not guarantee the order of headers in the outgoing requests.
 
+#### page.setGeolocation(options)
+- `options`
+  - `latitude` <[number]> Latitude between -90 and 90.
+  - `longitude` <[number]> Longitude between -180 and 180.
+  - `accuracy` <[number]> Optional non-negative accuracy value.
+- returns: <[Promise]>
+
+Sets the page's geolocation.
+
+```js
+await page.setGeolocation({latitude: 59.95, longitude: 30.31667});
+```
+
+> **NOTE** Consider using [browserContext.overridePermissions](#browsercontextoverridepermissionsorigin-permissions) to grant permissions for the page to read its geolocation.
+
 #### page.setJavaScriptEnabled(enabled)
 - `enabled` <[boolean]> Whether or not to enable JavaScript on the page.
 - returns: <[Promise]>

lib/Page.js

@@ -144,6 +144,20 @@ class Page extends EventEmitter {
     });
   }
 
+  /**
+   * @param {!{longitude: number, latitude: number, accuracy: (number|undefined)}} options
+   */
+  async setGeolocation(options) {
+    const { longitude, latitude, accuracy = 0} = options;
+    if (longitude < -180 || longitude > 180)
+      throw new Error(`Invalid longitude "${longitude}": precondition -180 <= LONGITUDE <= 180 failed.`);
+    if (latitude < -90 || latitude > 90)
+      throw new Error(`Invalid latitude "${latitude}": precondition -90 <= LATITUDE <= 90 failed.`);
+    if (accuracy < 0)
+      throw new Error(`Invalid accuracy "${accuracy}": precondition 0 <= ACCURACY failed.`);
+    await this._client.send('Emulation.setGeolocationOverride', {longitude, latitude, accuracy});
+  }
+
   /**
    * @return {!Puppeteer.Target}
    */

test/page.spec.js

@@ -128,6 +128,30 @@ module.exports.addTests = function({testRunner, expect, headless}) {
     });
   });
 
+  describe('Page.setGeolocation', function() {
+    it('should work', async({page, server, context}) => {
+      await context.overridePermissions(server.PREFIX, ['geolocation']);
+      await page.goto(server.EMPTY_PAGE);
+      await page.setGeolocation({longitude: 10, latitude: 10});
+      const geolocation = await page.evaluate(() => new Promise(resolve => navigator.geolocation.getCurrentPosition(position => {
+        resolve({latitude: position.coords.latitude, longitude: position.coords.longitude});
+      })));
+      expect(geolocation).toEqual({
+        latitude: 10,
+        longitude: 10
+      });
+    });
+    it('should throw when invalid longitude', async({page, server, context}) => {
+      let error = null;
+      try {
+        await page.setGeolocation({longitude: 200, latitude: 10});
+      } catch (e) {
+        error = e;
+      }
+      expect(error.message).toContain('Invalid longitude "200"');
+    });
+  });
+
   describe('Page.evaluate', function() {
     it('should work', async({page, server}) => {
       const result = await page.evaluate(() => 7 * 3);