Refactors the `ng_rollup_bundle` rule to a macro that relies on
the `@bazel/rollup` package. This means that the rule no longer
deals with custom ESM5 flavour output, but rather only builds
prodmode ES2015 output. This matches the common build output
in Angular projects, and optimizations done in CLI where
ES2015 is the default optimization input.
The motiviation for this change is:
* Not duplicating rollup Bazel rules. Instead leveraging the official
rollup rule.
* Not dealing with a third TS output flavor in Bazel.The ESM5 flavour has the
potential of slowing down local development (as it requires compilation replaying)
* Updating the rule to be aligned with current CLI optimizations.
This also _fixes_ a bug that surfaced in the old rollup bundle rule.
Code that is unused, is not removed properly. The new rule fixes this by
setting the `toplevel` flag. This instructs terser to remove unused
definitions at top-level. This matches the optimization applied in CLI
projects. Notably the CLI doesn't need this flag, as code is always
wrapped by Webpack. Hence, the unused code eliding runs by default.
PR Close#37623
Within an Angular package, it can happen that there are
entry-points which do not contain features that belong into
an `@NgModule` or need metadata files to be generated.
For example: the `cdk`, `cdk/testing` and `cdk/coercion`
entry-points. Besides other entry-points in the `cdk`
package, those entry-points do not need metadata to
be generated and no not use the `ng_module` rule.
Currently the "ng_package" rule properly picks up such
entry-points and builds bundles, does downleveling etc.
The only thing it misses is that no `package.json` files
are generated for the entry-point. This means that consumers
will not be able to use these entry-points built with "ts_library"
(except accessing the individual bundlings explicitly).
The "ng_package" rule should follow the full APF specification
for such entry-points. Partially building bundles and doing the
downleveling is confusing and a breaking issue.
The motifivation of supporting this (besides making the
rule behavior consistent; the incomplete output is not
acceptable), is that using the "ng_module" rule does
not make sense to be used for non-Angular entry-points.
Especially since it depends on Angular packages to
be specified as Bazel action inputs just to compile
vanilla TypeScript with `@angular/compiler-cli`.
PR Close#32610