4.3 KiB
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
:
$ 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
andyarn 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 correspondingpackage.json
files (wrt the non-local dependencies - i.e. dependencies whose versions do not start withfile:
).You can update a
yarn.lock
file by runningyarn 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: 18f2ecdffd/lib/Launcher.js (L91)
And from the flags that the Karma ChromeHeadless
browser passes to Chrome: 5f70a76de8/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