This change moves information from instructions to declarative position:
- `ɵɵallocHostVars(vars)` => `DirectiveDef.hostVars`
- `ɵɵelementHostAttrs(attrs)` => `DirectiveDef.hostAttrs`
When merging directives it is necessary to know about `hostVars` and `hostAttrs`. Before this change the information was stored in the `hostBindings` function. This was problematic, because in order to get to the information the `hostBindings` would have to be executed. In order for `hostBindings` to be executed the directives would have to be instantiated. This means that the directive instantiation would happen before we had knowledge about the `hostAttrs` and as a result the directive could observe in the constructor that not all of the `hostAttrs` have been applied. This further complicates the runtime as we have to apply `hostAttrs` in parts over many invocations.
`ɵɵallocHostVars` was unnecessarily complicated because it would have to update the `LView` (and Blueprint) while existing directives are already executing. By moving it out of `hostBindings` function we can access it statically and we can create correct `LView` (and Blueprint) in a single pass.
This change only changes how the instructions are generated, but does not change the runtime much. (We cheat by emulating the old behavior by calling `ɵɵallocHostVars` and `ɵɵelementHostAttrs`) Subsequent change will refactor the runtime to take advantage of the static information.
PR Close#34683
Prior to this change, the ExpressionChangedAfterChecked error thrown in Ivy was missing useful information that was available in View Engine, specifically: missing property name for proprty bindings and also the content of the entire property interpolation (only a changed value was displayed) if one of expressions was changed unexpectedly. This commit improves the error message by including the mentioned information into the error text.
PR Close#34381
Ivy uses R3Injector, but we are currently pulling in both the StaticInjector
(View Engine injector) and the R3Injector when running with Ivy. This commit
adds an ivy switch so calling Injector.create() pulls in the correct
implementation of the injector depending on whether you are using VE or Ivy.
This saves us about 3KB in the bundle.
PR Close#30219