Reworks the TCB for two-way bindings to make them simpler and to avoid regressions for two-way bindings to generic inputs. The new TCB looks as follows:
```
var _t1: Dir;
var _t2 = _t1.input;
(_t1 as typeof _t2 | WritableSignal<typeof _t2>) = expression;
```
PR Close#54252
Currently, when two components are named `TestComponent`, and both would
use e.g. control flow. Templates would be generated by the compiler and
those would conflict at runtime because the names for the template
functions are not ensured to be unique.
This seems like a more general problem that could be tackled in the
future in the template pipeline by always using the `ConstantPool`, but
for now, we should be good already, given us ensuring the `baseName`'s are
always unique.
PR Close#54273
Fixes that `@defer` blocks weren't recognizing default imports and generating the proper code for them. Default symbols need to be accessed through the `default` property in the `import` statement, rather than by their name.
PR Close#53695
One of the earlier commits separated one-way and two-way bindings which ended up breaking some internal targets, because it changed the assignment order. These changes bring back the old order.
PR Close#54154
Updates the template definition builder to emit the new format for the listener side of two-way bindings.
```js
// Before
listener("ngModelChange", function($event) {
return ctx.name = $event;
});
// After
ɵɵtwoWayListener("ngModelChange", function($event) {
ɵɵtwoWayBindingSet(ctx.name, $event) || (ctx.name = $event);
return $event;
});
```
PR Close#54154
Currently the listener side two-way listeners are parsed by appending `=$event` to the raw expression. This is problematic, because:
1. It can interfere with other expressions (see #37809).
2. It can lead to confusing error messages because users will see code that they didn't write.
3. It doesn't allow us to further manipulate the expression.
These changes remove the logic that appends `=$event` to resolve the issue. There's also some new logic that checks the expression after it has been parsed to ensure that the result is an assignable expression.
Subsequent commits will update the code that emits the expression to add back the `$event` assignment where it's needed.
PR Close#54154
Adds the following new instructions:
* `twoWayBindingSet` - used to assign values inside of the listener side of a two-way binding. Currently a noop, but will come into play later.
* `twoWayListener` - used to bind a two-way listener. Currently calls directly into `listener`, but it may be useful in the future.
PR Close#54154
Reworks the compiler so that it generates a `twoWayProperty` instruction, instead of `property`, for the property side of a two-way binding. Currently the new instruction passes through to `property`, but it'll have some two-way-binding-specific logic in subsequent PRs.
PR Close#54154
During the template parsing stage two-way bindings are split up into a property and event binding. All the downstream code treats these binding the same as their one-way equivalents. For some future work we'll have to distinguish between the two so these changes update the `BoundElementProperty.type` and `ParsedEvent.type` to include a `TwoWay` type. All existing call-sites have been updated to treat `TwoWay` the same as `Property`/`Regular`, but more specialized logic will be added in the future.
PR Close#54065
The Template Pipeline is a brand new backend for the Angular compiler, replacing `TemplateDefinitionBuilder`. It generates the Ivy instructions corresponding to an input template (or host binding). The Template Pipeline has an all-new design based on an intermediate representation compiled over many phases, which will allow us to experiment with compiler changes more easily in the future.
With this commit, the template pipeline can now be enabled in any project via the `useTemplatePipeline` TSConfig option. However, it is still disabled by default.
PR Close#54057
In #53591, Andrew added local compliation support for defer blocks. However, this requires the ability to emit pre-generated static defer deps functions. We now also support that feature in Template Pipeline.
PR Close#54043
Collapses multiple sibling query advance statements into single
query advance invocations. This will help reducing generated code
for directives/components with many queries.
PR Close#54019
This commit ensures that libraries can use signal-based queries, and the
partial compilation output will capture their metadata.
The linker is updated to support parsing this.
Two notes:
1. Older linker versions are not capable of parsing this, so the minimum
version for signal-based queries is adjusted when such are used.
2. We only emit `isSignal` metadata for queries when signal queries are
used. This enables libraries to continue supporting older linker
versions, if signal-based queries are not used.
PR Close#53978
This commit uses the initializer API recognition that we built for
signal-based inputs, and teaches the compiler to recognize class members
that refer to `viewChild`, `viewChildren`, `contentChild` or
`contentChildren`. Those will declare signal-based view or content queries.
PR Close#53978
This commit introduces the compiler output generation for signal-based
queries. Signal-based queries will have new creation-mode instructions
and update instructions to advance the current query indices in the
global shared context.
An output like the following is the expected output for signal-based
queries:
```
i0.ɵɵdefineComponent({
viewQuery: function App_Query(rf, ctx) {
if (rf & 1) {
i0.ɵɵviewQuery(ctx.d, _c0, 5);
i0.ɵɵviewQuerySignal(ctx.ds1, _c0, 5);
i0.ɵɵviewQuerySignal(ctx.ds2, _c0, 5);
}
if (rf & 2) {
let _t;
// only change-detected queries need explicit refresh
i0.ɵɵqueryRefresh(_t = i0.ɵɵloadQuery()) && (ctx.d = _t.first);
// we bump up current query index by 2 positions since there are 2 signal-based queries
i0.ɵɵqueryAdvance(2);
}
…
},
…
});
```
Note: For now, the collapsing of multiple advance instructions is not
implemented. This will be a follow-up.
Note 2: A couple of query helpers are now in their own file. This makes
it easier to focus on query-specific compiler code. The new function is
called `createQueryCreateCall`, which is a modified variant of the
existing function that previously only generated query parameters.
PR Close#53978
This commit adds extra logic to produce a diagnostic in case `@Component.deferredImports` contain types from imports that also bring eager symbols. This would result in retaining a regular import and generating a dynamic import, which would not allow to defer-load dependencies.
PR Close#53899
This commit updates the logic of the `TemplateDefinitionBuilder` to support local compilation and generate a single dependency function for all explicitly deferred deps within a component.
PR Close#53591
As part of testing we did accidentally use `bitwiseAnd` for the input
flags, given we started without an extra flag for `HasTransform`.
This commit teaches the compiler to support emitting bitwise OR
and uses it when combining input flags, fully re-enabling transforms
for signal components after the new flag mechanism was introduced in
previous commits.
PR Close#53808
This commit changes the `HasTransform` flag to be only concerned with
decorator inputs. This allows us to automatically detect signal input
transforms without reliance on the flag, resulting in less complexity in
the compiler (as outlined in the design doc) and various other places,
while it also allows us to simplify JIT support for signal inputs
because there would be no need to capture the "hasTransform" state in
the decorator so that JIT can generate the according input flags.
`isSignal` will still persist as an input flag to allow for monomorphic
and highly efficient distinguishing at runtime, whether an input is
signal based or not. JIT transform will also need to propagate this
information to the runtime somehow.
PR Close#53808
We generate `advance` instructions before most update instructions and the majority of `advance` calls are advancing by one. We can save some bytes for the most common case by omitting the parameter for `advance(1)` altogether.
PR Close#53845
Instead of computing the bit input flags at compile-time and inling
the final bit flag number, we will use the `InputFlags` enum directly.
This is a little more code in the compiler side, but will allow us to
have better debuggable development code, and also prevents problems
where runtime flag bitmasks differ from the compiler flag bitmasks.
This is in practice a noop for optimized applications as the enum values
would be inlined anyway. This matches existing compiler emit for e.g.
change detection strategy, or view encapsulation enums.
PR Close#53571
This commit introduces a new enum for capturing additional metadata
about inputs. Called `InputFlags`. These will be built up at compile
time and then propagated into the runtime logic, in a way that does
not require additional lookup dictionaries data structures, or
additional memory allocations for "common inputs" that do not have any flags.
The flags will incorporate information on whether an input is signal
based. This can then be used to avoid megamorphic accesses when such
input is set- as we'd not need to check the input field value. This also
avoids cases where an input signal may be used as initial value for an
input (as we'd not incorrectly detect the input as a signal input then).
The new metadata emit will be useful for incorporating additional
metadata for inputs, such as whether they are required etc (although
required inputs are a build-time only construct right now- but this is a
good illustration of why input flags can be useful). An alternative
could have been to have an additional boolean entry for signal inputs,
but allocating a number with more flexible input flags seems more future
proof and more reasonable andreadable.
More information on the megamorphic access when updating an input
signal
https://docs.google.com/document/d/1FpnFruviKb6BFTQfMAP2AMEqEB0FI7z-3mT_qm7lzX8/edit.
PR Close#53571
Template pipeline previously mangled CSS property names like
`--camelCase` when used in host style bindings. Note: It still *does*
mangle these names in static style attrs, both in host bindings and on
elements. This is clearly wrong, but is consistent with what TDB does
today.
PR Close#53665
The for loop tracking function doesn't allow references to local template variables, aside from `$index` and the item which are passed in as parameters. We enforce this by rewriting all variable references to the components scope.
The problem is that the logic that rewrites the references first walks the view tree and then checks if the variable is `$index` or the item. This is problematic in nested for loops, because it'll find the `$index` of the parent.
These changes resolve the issue by checking for `$index` and the item first.
Fixes#53600.
PR Close#53604
This commit adds the last remaining piece for signal input
type-checking. Bound values to signal inputs are already checked
properly at this point, but inference of generic directive/component
types through their inputs is not implemented.
This commit fixes this. To achieve this, there are a couple of potential
solutions. The generics of a directive are inferred based on input
value expressions using a so-called type constructor. The constructor
looks something like this:
```
const _ctor = <T>(v: Pick<Dir<T>, 'input1', 'input2'>) => Dir<T>;
_ctor({input1: expr1, input2: expr2});
```
This works very well for non-signal inputs where the class member is
directly holding the input values. For signal inputs, this does NOT
work because the class member will actually hold the `InputSignal`
instance. There are a couple of solutions to this:
1. Calling `_ctor` with an `InputSignal<typeof value>`
2. Converting the `_ctor` input signal fields to their write types
(unwrapping the input signals).
We've decided to go with the second option as TypeScript is very
sensitive with assignments and its checks. i.e. co-variance,
contravariance or bivariance. Semantically it makes more sense to unwrap
the input signal "write type" directly and "assign to it". This is safer
and conceptually also easier to follow. A type constructor continues to
only receive the "expresison values". This simplifies code as well.
It's worth noting that the unwrapping as per option 2 also comes at a
cost. We need to be able to generate imports in type constructors. This
was not possible until the previous commit because inline type constructors
did not have an associated type-check block `Environment` and we were
missing access to expression translation and correct import generation.
Overall, solution 2 is now implemented as works as expected. This commit
adds additional unit tests to ensure this.
PR Close#53521
Signal inputs do not need coercion members for their transforms. That is
because the `InputSignal` type- which is accessible in the class member-
already holds the type of potential "write values". This eliminates the
need for coercion members which were simply used to somehow capture this
write type (especially when libraries are consumed and only `.d.ts` is
available).
We can simplify this, and also significantlky loosen restrictions
of transform functions- given that we can fully rely on TypeScript for
inferring the type. There is no requirement in being able to
"transplant" the type into different places- hence also allowing
supporting transform functions with generics, or overloads.
In a follow-up commit, once more parts are place, there will be some
compliance tests to ensure these new "loosend restrictions".
PR Close#53521
This commit introduces the initial type-checking for signal inputs.
To enable type-checking od signal inputs, there are a couple of tricks
needed. It's not trivial as it would look like at first glance.
Initial attempts could have been to generate additional statements in
type-checking blocks for signal inputs to simply call a method like
`InputSignal#applyNewValue`. This would seem natural, as it would match
what will happen at runtime, but this would break the language-service
auto completion in a highly subtle way. Consider the case where multiple
directives match the same input. Consider the directives have some
overlap in accepted input values, but they also have distinct diverging
values, like:
```ts
class DirA {
value = input<'apple'|'shared'>();
}
class DirB {
value = input<'orange'|'shared'>();
}
```
In such cases, auto completion for the binding expression should suggest
the following values: `apple`, `shared`, `orange` and `undefined`.
The language service achieves this by getting completions in the
type-check block where the user expression would live. This BREAKS if
we'd have multiple places where the expression from the user is used.
Two different places, or more, surface additional problems with
diagnostic collection. Previously diagnostics would surface the union
type of allowed values, but with multiple places, we'd have to work with
potentially 1+ diagnostics. This is non-ideal.
Another important consideration is test coverage. It might sound
problematic to consider the existing test infrastructure as relevant,
but in practice, we have thousands of diagnostic type check block tests
that would greatly benefit if the general emit structure would still
match conceptually. This is another bonus argument on why changing the
way inputs are applied is probably an option we should consider as a
last resort.
Ultimately, there is a good solution where we unwrap directive signal
inputs, based on metadata, and access a brand type field on the
`InputSignal`. This ensures auto-completion continues to work as is, and
also the structure of type check blocks doesn't change conceptually. In
future commits we also need to handle type-inference for generic signal
inputs.
Note: Another alternative considered, in terms of using metadata or not.
We could have type helpers to unwrap signal inputs using type helpers
like: `T extends InputSignal<any, WriteT> ? WriteT : T`. This would
allow us to drop the input signal metadata dependency, but in reality,
this has a few issues:
- users might have `@Input`'s passing around `InputSignal`'s. This is
unlikely, but shows that the solution would not be fully correct.
- we need the metadata regardless, as we plan on accessing it at runtime
as well, to distinguish between signal inputs and normal inputs when
applying new values. This was not clear when this option was
considered initially.
PR Close#53521
This commit captures the metadata on whether an input is signal based or
not, in the `.d.ts` of directives and components. This exposes this
information to consumers of the directives. This is needed because
libraries may use signal inputs, and we need to know whether bound
inputs to this library are signal-based or not- so that we can generate
proper type-checking code (account for `InputSignal` or not).
Additionally, this commit introduces a new structure for the partial
compilation output of directive inputs. With the current emit, inputs
are captured in a data structure that is equivalent to the internal data
structure passed to `defineDirective` (the full compilation output).
This worked fine as we only captured a few strings, but in ends up
being a bad practice because partial compilation output should NOT
capture internal data structures that might be specific to a certian
Angular core version. Instead, we introduce a new "future proof"
structure that:
- can hold additional metadata in backwards-compatible ways, like
`isSignal` or `isRequired`.
- can be parsed trivially using the `AstHost` for the linker, instead of
having to unwrap/parse an array structure.
The new structure is only emitted when we discover that some inputs are
signal based (or ultimately end up configuring input flags). This is
done for backwards compatibility, so that libraries without signal
inputs remain compatible with older linker versions. In the future,
this might be the only emit.
Compliance tests for this follow in future commits, when the linker
portion is also in place. This commit specialices on the code
generation. With the linker, and compliance test infrastructure fixed
(that is broken right now), we can test the full integration.
PR Close#53521
Adds support for sanitizing host bindings. Since the tag name of the
element the host binding is being set on isn't always known, we have to
consider multiple possible security contexts.
This commit also adds additional tests to help verify correct behavior
of the sanitization logic for different edge cases.
PR Close#53513
Use the DomElementSchemaRegistry to determine the correct security
context for static attributes, and pass it along during ingestion. Then
during the resolve sanitizers phase, use the security context to
determine if a trusted value function is needed
PR Close#53473
To support the development of component specific HMR capabilities, the build/serve
tooling may need to directly process styles to match the view encapsulation
expectations of individual components. To allow for this scenario and to avoid tooling
to need to re-implement the emulated encapsulation logic, an private API is now
available in the `@angular/compiler` package named `encapsulateStyle` that converts
a stylesheet content string to an encapsulated form. This function is not considered
part of the public API nor does it have any of its respective support or versioning guarantees.
PR Close#53363
This commit fixes an issue where having an expression with nullish coalescing in styling host bindings leads to JS errors due to the fact that a declaration for a temporary variable was not included into the generated code.
Resolves#53295.
PR Close#53305
These changes expose the `ngContentSelectors` and `preserveWhitespaces` metadata to the TCB so they can be used in the next commit to implement a new diagnostic.
PR Close#53190
When doing directive matching in the compiler, we need to be able to create a selector from an AST node. We already have the utility, but these changes simplify the public API and expose it so it can be used in `compiler-cli`.
PR Close#53190
Adds support for inheriting host directives from the parent class. This is consistent with how we inherit other features like host bindings.
Fixes#51203.
PR Close#52992
When blocks were initially implemented, they were represented as containers in the i18n AST. This is problematic, because block affect the structure of the message.
These changes introduce a new `BlockPlaceholder` AST node and integrate it into the i18n pipeline. With the new node blocks are represented with the `START_BLOCK_<name>` and `CLOSE_BLOCK_<name>` placeholders.
PR Close#52958
These changes expose the `ngContentSelectors` and `preserveWhitespaces` metadata to the TCB so they can be used in the next commit to implement a new diagnostic.
PR Close#52726
When doing directive matching in the compiler, we need to be able to create a selector from an AST node. We already have the utility, but these changes simplify the public API and expose it so it can be used in `compiler-cli`.
PR Close#52726
The `$first`, `$last`, `$even` and `$odd` variables in `@for` loops aren't defined on the template context of the loop, but are computed based on `$index` and `$count` (e.g. `$first` is defined as `$index === 0`). We do this calculation by looking up `$index` and `$count` when one of the variables is used.
The problem is that all `@for` loop variables are available implicitly which means that when a nested loop tries to rewrite a reference to an outer loop computed variable, it finds its own `$index` and `$count` first and it doesn't look up the ones on the parent at all. This means that the calculated values will be incorrect at runtime.
These changes work around the issue by defining nested-level-specific variable names that can be used for lookups (e.g. `$index` at level `2` will also be available as `ɵ$index_2`). This isn't the most elegant solution, however the `TemplatDefitinionBuilder` wasn't set up to handle shadowed variables like this and it doesn't make sense to refactor it given the upcoming template pipeline.
Fixes#52917.
PR Close#52931
Reworks the `repeater` instruction to go through `advance`, instead of passing in the index directly. This ensures that lifecycle hooks run at the right time and that we don't throw "changed after checked" errors when we shouldn't be.
Fixes#52885.
PR Close#52935