d4cee514f6
Originally, the ivy_switch mechanism used Bazel genrules to conditionally compile one TS file or another depending on whether ngc or ngtsc was the selected compiler. This was done because we wanted to avoid importing certain modules (and thus pulling them into the build) if Ivy was on or off. This mechanism had a major drawback: ivy_switch became a bottleneck in the import graph, as it both imports from many places in the codebase and is imported by many modules in the codebase. This frequently resulted in cyclic imports which caused issues both with TS and Closure compilation. It turns out ngcc needs both code paths in the bundle to perform the switch during its operation anyway, so import switching was later abandoned. This means that there's no real reason why the ivy_switch mechanism needed to operate at the Bazel level, and for the ivy_switch file to be a bottleneck. This commit removes the Bazel-level ivy_switch mechanism, and introduces an additional TypeScript transform in ngtsc (and the pass-through tsc compiler used for testing JIT) to perform the same operation that ngcc does, and flip the switch during ngtsc compilation. This allows the ivy_switch file to be removed, and the individual switches to be located directly next to their consumers in the codebase, greatly mitigating the circular import issues and making the mechanism much easier to use. As part of this commit, the tag for marking switched variables was changed from __PRE_NGCC__ to __PRE_R3__, since it's no longer just ngcc which flips these tags. Most variables were renamed from R3_* to SWITCH_* as well, since they're referenced mostly in render2 code. Test strategy: existing test coverage is more than sufficient - if this didn't work correctly it would break the hello world and todo apps. PR Close #26550 |
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.. | ||
bazel | ||
cli-hello-world | ||
dynamic-compiler | ||
hello_world__closure | ||
hello_world__systemjs_umd | ||
i18n | ||
injectable-def | ||
language_service_plugin | ||
ng_elements | ||
ng_update | ||
ngcc | ||
platform-server | ||
typings_test_ts31 | ||
.gitignore | ||
README.md | ||
_payload-limits.json | ||
run_tests.sh |
README.md
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 just like we would publish it to npm, then install the distribution into each app.
To test Angular CLI applications, we use the integration test cli-hello-world
.
When a significant change is released in the CLI, the application should be updated with ng update
:
$ cd integration
$ ng update
# ng build
# ng test
# typescript version
Render3 tests
The directory hello_world_cli
contains a test for render3 used with the angular cli.
If the Angular CLI is modified to generate a render3 application this should be replaced with that project.
If the render3 is updated to support the Angular 5 bootstrap a version of this project should be created that uses the Angular 5 bootstrap.
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
.
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.