This commit bundles 3 important changes, with the goal of enabling tree-shaking
of services which are never injected. Ordinarily, this tree-shaking is prevented
by the existence of a hard dependency on the service by the module in which it
is declared.
Firstly, @Injectable() is modified to accept a 'scope' parameter, which points
to an @NgModule(). This reverses the dependency edge, permitting the module to
not depend on the service which it "provides".
Secondly, the runtime is modified to understand the new relationship created
above. When a module receives a request to inject a token, and cannot find that
token in its list of providers, it will then look at the token for a special
ngInjectableDef field which indicates which module the token is scoped to. If
that module happens to be in the injector, it will behave as if the token
itself was in the injector to begin with.
Thirdly, the compiler is modified to read the @Injectable() metadata and to
generate the special ngInjectableDef field as part of TS compilation, using the
PartialModules system.
Additionally, this commit adds several unit and integration tests of various
flavors to test this change.
PR Close#22005
All of the providers in a module get compiled into a module definition in the
factory file. Some of these providers are for the actual module types, as those
are available for injection in Angular. For tree-shakeable tokens, the runtime
needs to be able to distinguish which modules are present in an injector.
This change adds a NodeFlag which tags those module providers for later
identification.
PR Close#22005
- Fix the case when first dynamic values are NO_CHANGE
- Do not store the static texts (even indexes) as bindings,
- Do not diff static texts (they do not change),
- Do not stringify static texts,
- Remove superfluous values walking.
PR Close#21881
By adding attributes on the <ng-content> element template authors
can decide how content should be re-projected (or, in other words:
which selectors should match re-projected content).
PR Close#21935
Implement NgOnChangesFeature, ViewContainerRef, TemplateRef,
and the renderEmbeddedTemplate instruction, and wire together the
pieces required for the ngForOf directive to work.
PR Close#21430
To prepare for pending ngForOf work, the dep from instructions -> query
should be broken. This will enable a dep from di -> instructions while
avoiding a di -> instructions -> query -> di cycle.
Analyzing this cycle also uncovered another problem: the implementation
of query() breaks tree-shaking through a hard dependency on DI concepts
of TemplateRef, ElementRef, ViewContainerRef. This is fundamentally due
to how query() can query for those values without any configuration.
Instead, this fix introduces the concept by employing the strategy
pattern, and redefining QueryReadType to pass a function which will
return one of the above values. This strategy is then used for 'read'
instead of an enum in cases where special values should be read from
the DI system.
PR Close#21430
assertLessThan() actually does the opposite of what it advertises.
It's only through luck that existing asserts have not failed
before. This changes assertLessThan to actually assert that the
value is less than something.
PR Close#21430