George Kalpakas 669df70da5 fix(ivy): ensure DebugNode/DebugElement are tree-shakeable in Ivy (#35003)
There are different `DebugNode`/`DebugElement` implementations (and
associated helper functions) for ViewEngine and Ivy. Additionally, these
classes/functions, which are defined inside the `core` package, are
imported by the `platform-browser` package.

Previously, this code was not tree-shaken as expected in Ivy. #30130
partially addressed the issue, but only for the case where `core` and
`platform-browser` end up in the same closure after webpack's scope
hoisting. In cases where this is not the case, our webpack/terser based
tooling is not capable of tree-shaking it.

This commit fixes the problem, by ensuring that the code retained in Ivy
mode (due to the cross-package import) does not unnecessarily reference
`DebugNode`/`DebugElement`, allowing the code to be tree-shaken away.
This results in a 7.6KB reduction in the size of the main angular.io
bundle.

Jira issue: [FW-1802](https://angular-team.atlassian.net/browse/FW-1802)

PR Close #35003
2020-01-28 15:57:57 -08:00
..

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 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.