Previously the ngfactory shim generator in ngtsc would always write two
imports in the factory file shims:
1) an import to @angular/core
2) an import to the base file
If the base file has no exports, import #2 would be empty. This turns out
to cause issues downstream.
This commit changes the generated shim so if there are no exports in the
base file, the generated shim is empty too.
PR Close#27470
This commit adds generation of .ngsummary.js shims alongside .ngfactory.js
shims when generated files are enabled.
Generated .ngsummary shims contain a single, null export for every exported
class with decorators that exists in the original source files. Ivy code
does not depend on summaries, so these exist only as a placeholder to allow
them to be imported and their values passed to old APIs. This preserves
backwards compatibility.
Testing strategy: this commit adds a compiler test to verify the correct
shape and contents of the generated .ngsummary.js files.
PR Close#26495
This commit refactors the shim host to be agnostic to the shims being
generated, and provides an API for generating additional shims besides
the .ngfactory.js. This will be used in a following commit to generate
.ngsummary.js shims.
Testing strategy: this refactor introduces no new behavior, so it's
sufficient that the existing tests for factory shim generation continue
to pass.
PR Close#26495
This simple refactor of the build rules renames the .ngfactory.js shim
generator to 'shims' instead of 'factories', in preparation for adding
.ngsummary.js shim generation.
Testing strategy: this commit does not introduce any new behavior and
merely moves files and symbols around. It's sufficient that the existing
ngtsc tests pass.
PR Close#26495
