Greg Magolan acfd0edd38 test: use puppeteer in integration tests and to download correct chromedriver (#35049)
This means integration tests no longer need to depend on a $CI_CHROMEDRIVER_VERSION_ARG environment variable to specify which chromedriver version to download to match the locally installed chrome. This was bad DX and not having it specified was not reliable as webdriver-manager would not always download the chromedriver version to work with the locally installed chrome.

webdriver-manager update --gecko=false --standalone=false $CI_CHROMEDRIVER_VERSION_ARG is now replaced with node webdriver-manager-update.js in the root package.json, which checks which version of chrome puppeteer has come bundled with & downloads informs webdriver-manager to download the corresponding chrome driver version.

Integration tests now use "webdriver-manager": "file:../../node_modules/webdriver-manager" so they don't have to waste time calling webdriver-manager update in postinstall

"// resolutions": "Ensure a single version of webdriver-manager which comes from root node_modules that has already run webdriver-manager update",
"resolutions": {
"**/webdriver-manager": "file:../../node_modules/webdriver-manager"
}
This should speed up each integration postinstall by a few seconds.

Further, integration test package.json files link puppeteer via file:../../node_modules/puppeteer which is the ideal situation as the puppeteer post-install won't download chrome if it is already downloaded. In CI, since node_modules is cached it should not need to download Chrome either unless the node_modules cache is busted.

NB: each version of puppeteer comes bundles with a specific version of chrome. Root package.json & yarn.lock currently pull down puppeteer 2.1.0 which comes with chrome 80. See https://github.com/puppeteer/puppeteer#q-which-chromium-version-does-puppeteer-use for more info.

Only two references to CI_CHROMEDRIVER_VERSION_ARG left in integration tests at integration/bazel-schematics/test.sh which I'm not entirely sure how to get rid of it

Use a lightweight puppeteer=>chrome version mapping instead of launching chrome and calling browser.version()

Launching puppeteer headless chrome and calling browser.version() was a heavy-handed approach to determine the Chrome version. A small and easy to update mappings file is a better solution and it means that the `yarn install` step does not require chrome shared libs available on the system for its postinstall step

PR Close #35049
2020-02-11 13:16:52 -08:00

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# Integration tests for Angular
This directory contains end-to-end tests for Angular. Each directory is a self-contained application
that exactly mimics how a user might expect Angular to work, so they allow high-fidelity
reproductions of real-world issues.
For this to work, we first build the Angular distribution via `./scripts/build-packages-dist.js`, then
install the distribution into each app.
To test Angular CLI applications, we use the `cli-hello-world-*` integration tests.
When a significant change is released in the CLI, the applications should be updated with
`ng update`:
```bash
$ cd integration/cli-hello-world[-*]
$ yarn install
$ yarn ng update @angular/cli @angular-devkit/build-angular
$ yarn build
$ yarn test
```
Afterwards the `@angular/cli` and `@angular-devkit/build-angular` should be reverted to the `file:../` urls
and the main `package.json` should be updated with the new versions.
## Render3 tests
The directory `cli-hello-world-ivy-compat` contains a test for render3 used with the angular cli.
The `cli-hello-world-ivy-minimal` contains a minimal ivy app that is meant to mimic the bazel
equivalent in `packages/core/test/bundling/hello_world`, and should be kept similar.
## Writing an integration test
The API for each test is:
- Each sub-directory here is an integration test
- Each test should have a `package.json` file
- The test runner will run `yarn` and `yarn test` on the package
This means that the test should be started by test script, like
```
"scripts": {"test": "runProgramA && assertResultIsGood"}
```
Note that the `package.json` file uses a special `file:../../dist` scheme to reference the Angular
packages, so that the locally-built Angular is installed into the test app.
Also, beware of floating (non-locked) dependencies. If in doubt, you can install the package
directly from `file:../../node_modules`.
> WARNING
>
> Always ensure that `yarn.lock` files are up-to-date with the corresponding `package.json` files
> (wrt the non-local dependencies - i.e. dependencies whose versions do not start with `file:`).
>
> You can update a `yarn.lock` file by running `yarn install` in the project subdirectory.
## Running integration tests
```
$ ./integration/run_tests.sh
```
The test runner will first re-build any stale npm packages, then `cd` into each subdirectory to
execute the test.
## Browser tests
For integration tests we use the puppeteer provisioned version of Chrome. For both Karma and Protractor tests we set a number of browser testing flags. To avoid duplication, they will be listed and explained here and the code will reference this file for more information.
### No Sandbox: --no-sandbox
The sandbox needs to be disabled with the `--no-sandbox` flag for both Karma and Protractor tests, because it causes Chrome to crash on some environments.
See: http://chromedriver.chromium.org/help/chrome-doesn-t-start
See: https://github.com/puppeteer/puppeteer/blob/v1.0.0/docs/troubleshooting.md#chrome-headless-fails-due-to-sandbox-issues
### Headless: --headless
So that browsers are not popping up and tearing down when running these tests we run Chrome in headless mode. The `--headless` flag puts Chrome in headless mode and a number of other flags are recommended in this mode as well:
* `--headless`
* `--disable-gpu`
* `--disable-dev-shm-usage`
* `--hide-scrollbars`
* `--mute-audio`
These come from the flags that puppeteer passes to chrome when it launches it in headless mode: https://github.com/puppeteer/puppeteer/blob/18f2ecdffdfc70e891750b570bfe8bea5b5ca8c2/lib/Launcher.js#L91
And from the flags that the Karma `ChromeHeadless` browser passes to Chrome: https://github.com/karma-runner/karma-chrome-launcher/blob/5f70a76de87ecbb57f3f3cb556aa6a2a1a4f643f/index.js#L171
#### Disable shared memory space: --disable-dev-shm-usage
The `--disable-dev-shm-usage` flag disables the usage of `/dev/shm` because it causes Chrome to crash on some environments.
On CircleCI, the puppeteer provisioned Chrome crashes with `CI we get Root cause: org.openqa.selenium.WebDriverException: unknown error: DevToolsActivePort file doesn't exist which resolves` without this flag.
See: https://github.com/puppeteer/puppeteer/blob/v1.0.0/docs/troubleshooting.md#tips
See: https://stackoverflow.com/questions/50642308/webdriverexception-unknown-error-devtoolsactiveport-file-doesnt-exist-while-t