fix(testing): Skip puppeteer install

fixes #1529

Squashed commit of the following:

commit 8e57e7e
Author: Romulo Cintra <romulocintra@gmail.com>
Date:   Thu May 23 15:44:07 2019 +0200

    feat: conditional Lazyload of puppeteer

commit c58e790
Merge: 1125d3c c4d7c0d
Author: Romulo Cintra <romulocintra@gmail.com>
Date:   Thu May 23 15:21:13 2019 +0200

    Merge branch 'master' of github.com:ionic-team/stencil into feature/skip-install-puppeteer

commit 1125d3c
Author: Romulo Cintra <romulocintra@gmail.com>
Date:   Sat May 18 22:41:35 2019 +0200

    wip: skip puppeteer install

package.json

@@ -132,6 +132,7 @@
     "jest-cli": "~24.8.0",
     "pixelmatch": "4.0.2",
     "puppeteer": "~1.17.0",
+    "puppeteer-core": "~1.17.0",
     "workbox-build": "~4.3.1"
   },
   "engines": {

scripts/build-testing.js

@@ -37,6 +37,7 @@ async function bundleTesting() {
       'path',
       'process',
       'puppeteer',
+      'puppeteer-core',
       'readline',
       'rollup',
       'rollup-plugin-commonjs',

src/cli/task-test.ts

@@ -12,10 +12,12 @@ export async function taskTest(config: d.Config) {
 
   if (config.flags && config.flags.e2e) {
     // if it's an e2e test, also make sure we're got
-    // puppeteer modules installed
+    // puppeteer modules installed and if browserExecutablePath is provided don't download Chromium use only puppeteer-core instead
+    const puppeteer = config.testing.browserExecutablePath ? 'puppeteer-core' : 'puppeteer';
+
     ensureModuleIds.push(
       '@types/puppeteer',
-      'puppeteer'
+      puppeteer
     );
 
     if (config.flags.screenshot) {

src/testing/puppeteer/puppeteer-browser.ts

@@ -9,8 +9,9 @@ export async function startPuppeteerBrowser(config: d.Config) {
   }
 
   const env: d.E2EProcessEnv = process.env;
+  const puppeteerDep = config.testing.browserExecutablePath ? 'puppeteer-core' : 'puppeteer';
 
-  const puppeteerModulePath = config.sys.lazyRequire.getModulePath('puppeteer');
+  const puppeteerModulePath = config.sys.lazyRequire.getModulePath(puppeteerDep);
   const puppeteer = require(puppeteerModulePath);
   env.__STENCIL_PUPPETEER_MODULE__ = puppeteerModulePath;
   env.__STENCIL_BROWSER_WAIT_UNTIL = config.testing.browserWaitUntil;