When defer blocks have a reference-based trigger without a parameter, we infer it from the placeholder block. This requires some validations like ensuring that there's only one element in the placeholder. The validations are currently implemented at the parser level which can affect tools like linters that need to pass `preserveWhitespaces: true` in order to get accurate source mappings.
These changes move the validations into the template type checker so that they still get flagged, but much later in the process. Moving them over involves a bit more work, because the template type checker also sets `preserveWhitespaces: true`.
Fixes#61725.
PR Close#61747
In declaration-only emission mode, the compiler extracts the type
declarations (.d.ts) files without full type-checking, which is possible
with sufficient type annotations on exports that can be ensured by the
`isolatedDeclarations` TS compiler option.
This allows us to decouple type declaration emission from the actual
full compilation doing the type-checking, thereby removing the
edge between dependent TS files in the build action graph. In other
words, the compilation of a TS file no longer indirectly depends on the
compilation of all the TS files it imports through its dependency on
their type declarations, because the type declarations themselves no
longer depend on the compilation of their associated TS file.
Without the coupling between type declaration emission and compilation,
compilation time of a TS project is no longer bound dependent on the
depth of the TS dependency tree as we can now build the entire project
with just two entirely parallel phases: 1) emit the type declarations of
all TS files in parallel and 2) compile all TS files in parallel.
Since the Angular compiler adds static metadata fields to components,
directives, modules, pipes and services based on their respective class
annotations, it needs to actively partake in the type declaration
emission in order to provide the types for these static fields in the
declaration.
In this change, we add experimental support for a declaration-only
emission mode based on the local compilation mode, which already
operates without type-checking and access to external type information,
i.e. the same environment as is required for declaration-only emisssion.
Apart from the same restrictions applied in local compilation mode,
there are a few more restrictions imposed on code being compatible with
this initial and experimental implementation:
* No support for `@NgModule`s using external references.
* No support for `hostDirectives` in `@Component`s and `@Directive`s
using external references
* No support for `@Input` annotations with `transform`.
PR Close#61334
Adds a new diagnostic that ensures that a standalone component using custom structural directives in a template has the necessary imports for those directives.
Fixes#37322
PR Close#59443
The semantics for nullish coalescing (`??`) in Javascript/Typescript
differ slightly from the semantics in Angular templates. Mixing nullish
coalescing with logical and/or without parentheses is an error in
Javascript. This PR adds an extended diagnostic that can be enabled to
treat it as an error in Angular templates as well.
PR Close#60279
Historically Angular's type checking only extended to templates, however host bindings can contain expressions as well which can have type checking issues of their own. These changes expand the type checking infrastructure to cover the `host` object literal, `@HostBinding` decorators and `@HostListener` with full language service support coming in future commits.
Note that initially the new functionality is disabled by default and has to be enabled using the `typeCheckHostBindings` compiler flag.
PR Close#60267
Adds a new diagnostic that ensures that a standalone component using custom structural directives in a template has the necessary imports for those directives.
Fixes#37322
PR Close#59443
Add the `strictStandalone` flag to `angularCompilerOptions`. When set to
true, the compiler will require that all declarations of components,
directive, and pipes be standalone. When `standalone: false` is provided,
an error is raised.
Note that until the default value of the standalone flag is flipped, this
does not catch the case where a declaration does not specify a value for
`standalone`.
The default value of the `strictStandalone` flag is `false`.
PR Close#57935
Adds a new diagnostic that will report cases where a declaration is in the `imports` array, but isn't being used anywhere. The diagnostic is reported as a warning by default and can be controlled using the following option in the tsconfig:
```
{
"angularCompilerOptions": {
"extendedDiagnostics": {
"checks": {
"unusedStandaloneImports": "suppress"
}
}
}
}
```
**Note:** I'll look into a codefix for the language service in a follow-up.
Fixes#46766.
PR Close#57605
This configures whether or not to preserve whitespace content when extracting messages from Angular templates in the legacy (View Engine) extraction pipeline.
This includes several bug fixes which unfortunately cannot be landed without changing message IDs in a breaking fashion and are necessary to properly trim whitespace. Instead these bug fixes are included only when the new flag is disabled.
PR Close#56507
Adds a new extended diagnostic that will flag `@let` declarations that aren't used within the template. The diagnostic can be turned off through the `extendedDiagnostics` compiler option.
PR Close#57033
Adds a new extended diagnostic that will flag `@let` declarations that aren't used within the template. The diagnostic can be turned off through the `extendedDiagnostics` compiler option.
PR Close#57033
Integrates let declarations into the template type checker by producing corresponding constants in the TCB.
This also includes a couple of custom diagnostics to flag usages of let before they're declared and illegal writes to let declarations. We can't rely on TS for these checks, because it includes the variable name in the diagnostic.
PR Close#56199
An initializer API like `input`, `output`, or signal queries may not be
compatible with certain access levels. E.g. queries cannot work with ES
private class fields.
This commit introduces a check for access levels into the initializer
API recognition— enforcing that every initializer API *clearly*
specifies what type of access is allowed.
PR Close#54981
`TemplateDefinitionBuilder` is the legacy template compiler, and was replaced by Template Pipeline as the default in v17.3.
This PR attempts to delete `TemplateDefinitionBuilder`, `ExpressionConverter`, and various helpers (i18n context, style builder, property visitors, etc).
Consider this a first pass: a lot of code has not yet been deleted (e.g. old TDB-specific test cases), and I'm sure I have missed additional helper code.
PR Close#54757
A single error code is created to unify the common error pattern in local compilation mode where an imported const cannot be resolved, but needs to be resolved. This mainly happens for Angular decorator fields such as @Component.template.
The error messages are also upgraded to be more centered around this unifying theme.
PR Close#54230
As we are introducing the new `output()` function as an inituive
alternative to `@Output()` that matches with signal-based inputs,
this commit prepares the compiler to detect such initializer-based
outputs.
PR Close#54217
This commit includes a skeleton of how the tool `LocalCompilationExtraImportsTracker` is used in the overall compilation workflow end-to-end.
First of all, a new option `generateExtraImportsInLocalMode` is added, whose presence will make `LocalCompilationExtraImportsTracker` part of the compilation process. When this option is set an instance of `LocalCompilationExtraImportsTracker` is created within the NgCompiler. Then it is passed to the Ivy transformer and plumbed all the way down and the extra imports registered in it are added to the `ImportManager` instances before the imports are added from `ImportManager` to the generated file. This required adding a new method `generateSideEffectImport` to the `ImportManager`, which is an empty method and will be implemented in the subsequent commits.
This commit expected to make no change in the compilation behavior as the methods are not implemented yet.
PR Close#53543
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
This commit introduces three additional diagnostics for queries:
- If a query (either using decorator or signal-based) is declared on a
static class member, a diagnostic is raised.
- If a signal-based query is mixed with a query decorator, a diagnostic
is raised. Similar to signal inputs.
- If a singal-based query is also declared in the directive/component
class decorator metadata, a diagnostic is raised.
PR Close#54019
At the moment local compilation breaks for host directives because the current logic relies on global static analysis. This change creates a local version by cutting the diagnostics and copying the directive identifier as it is to the generated code without attempting to statically resolve it.
PR Close#53877
Currently when someone declares a signal or non-signal input on a static
class member, the compiler will not yield any diagnostic. We can detect
these mistakes and report a diagnostic to help our users.
PR Close#53808
This commit addds two diagnostics for two scenarios where signal inputs
are declared incorrectly:
- a signal input is also annotated with `@Input` in the TypeScript
sources.
- a signal input is also declared in the `inputs` option of
`@Directive/`@Component`.
PR Close#53808
These changes add an option to the `extendedDiagnostics` field that allows the check from #53190 to be disabled. This is a follow-up based on a recent discussion.
PR Close#53311
This is a follow-up to the fix from #52414. It adds a diagnostic that will tell users when a control flow is preventing its direct descendants from being projected into a specific component slot.
PR Close#53190
This is a follow-up to the fix from #52414. It adds a diagnostic that will tell users when a control flow is preventing its direct descendants from being projected into a specific component slot.
PR Close#52726
Orphan component is an anti-pattern in Angular where a component is rendered while the NgModule declaring it is not installed. It is not easy to capture this scenario, specially in compile time. But it is possible to capture a special case in runtime where the component is being rendered without its NgModule even loaded into the browser. This change adds a flag in cli compiler option to enable such checking, and throwing a runtime exception if it happens. Note that such check is only done in dev mode.
Currently the check requires some generated code that is behind ngJitMode flag (i.e., call to ɵɵsetNgModuleScope), and the new flag can be set only if JIT mode is enabled (i.e., supportJitMode=true) otherwise an error will be thrown.
The orphan component is a main blocker for rolling out local compilation in g3. This option is needed for identifying and isolating such cases.
PR Close#52061
If a trigger element can't be accessed from the defer block, we don't generate any instructions for it. These changes add a diagnostic that will surface the error to users.
PR Close#51922
Adds support for template type checking of the `track` expression of a `for` loop block. Tracking expressions are treated as any other expression for type checking, however we have some special validation that doesn't allow them to access template variables and local references.
PR Close#51690
