Previously, metadata registration (the recording of collected metadata
during analysis of directives, pipes, and NgModules) was only used to
produce the `LocalModuleScope`, and thus was handled by the
`LocalModuleScopeRegistry`.
However, the template type-checker also needs information about registered
directives, outside of the NgModule scope determinations. Rather than
reuse the scope registry for an unintended purpose, this commit introduces
new abstractions for metadata registration and lookups in a separate
'metadata' package, which the scope registry implements.
This paves the way for a future commit to make use of this metadata for the
template type-checking system.
Testing strategy: this commit is a refactoring which introduces no new
functionality, so existing tests are sufficient.
PR Close#29698
Previously, when the NgModule scope resolver discovered semantic errors
within a users NgModules, it would throw assertion errors. TODOs in the
codebase indicated these should become ts.Diagnostics eventually.
Besides producing better-looking errors, there is another reason to make
this change asap: these assertions were shadowing actual errors, via an
interesting mechanism:
1) a component would produce a ts.Diagnostic during its analyze() step
2) as a result, it wouldn't register component metadata with the scope
resolver
3) the NgModule for the component references it in exports, which was
detected as an invalid export (no metadata registering it as a
component).
4) the resulting assertion error would crash the compiler, hiding the
real cause of the problem (an invalid component).
This commit should mitigate this problem by converting scoping errors to
proper ts.Diagnostics. Additionally, we should consider registering some
marker indicating a class is a directive/component/pipe without actually
requiring full metadata to be produced for it, which would allow suppression
of errors like "invalid export" for such invalid types.
PR Close#29191
This commit splits apart selector_scope.ts in ngtsc and extracts the logic
into two separate classes, the LocalModuleScopeRegistry and the
DtsModuleScopeResolver. The logic is cleaned up significantly and new tests
are added to verify behavior.
LocalModuleScopeRegistry implements the NgModule semantics for compilation
scopes, and handles NgModules declared in the current compilation unit.
DtsModuleScopeResolver implements simpler logic for export scopes and
handles NgModules declared in .d.ts files.
This is done in preparation for the addition of re-export logic to solve
StrictDeps issues.
PR Close#28852