With this commit directives, components & pipes are standalone by default.
To be declared in an `NgModule`, those require now `standalone: false`.
PR Close#58169
For the HMR initializer block to support being used in a Vite setup with
import analysis, the import call expression needs to be a runtime generated
value and include the `@vite-ignore` special comment. Without the first,
Vite will error prior to loading the application. Without the second, a
warning will be shown for each import which is effectively each component
within the application when HMR is enabled.
PR Close#58173
Make it so that encapsulation for empty styles, styles containing only whitespace and comments, etc.
is handled the same way as with no styles at all.
Components without styles already have view encapsulation set to `None`
to avoid generating unnecessary attributes for style scoping, like `_ngcontent-ng-c1` (#27175)
If the component has an empty external styles file instead, the compiler would generate
a component definition without the `styles` field, but still using the default encapsulation.
This can result in runtime overhead if the developer forgets to delete the empty styles file
generated automatically for new components by Angular CLI.
Closes#16602
PR Close#57130
Consider a template with a context variable `a`:
```
<ng-template let-a>{{this.a}}</ng-template>
```
t push -fAn interpolation inside that template to `this.a` should intuitively read the class variable `a`. However, today, it refers to the context variable `a`, both in the TCB and the generated code.
In this commit, the above interpolation now refers to the class field `a`.
BREAKING CHANGE: `this.foo` property reads no longer refer to template context variables. If you intended to read the template variable, do not use `this.`.
Fixes#55115
PR Close#55183
The AOT compiler now has the capability to handle component stylesheet files as
external runtime files. External runtime files are stylesheets that are not embedded
within the component code at build time. Instead a URL path is emitted within a component's
metadata. When combined with separate updates to the shared style host and DOM renderer,
this will allow these stylesheet files to be fetched and processed by a development
server on-demand. This behavior is controlled by an internal compiler option `externalRuntimeStyles`.
The Angular CLI development server will also be updated to provide the serving functionality
once this capability is enabled. This capability enables upcoming features such as automatic
component style hot module replacement (HMR) and development server deferred stylesheet processing.
The current implementation does not affect the behavior of inline styles. Only the
behavior of stylesheet files referenced via component properties `styleUrl`/`styleUrls`
and relative template `link` elements are changed by enabling the internal option.
PR Close#57613
Adds the new `ɵɵreplaceMedata` function that can be used to replace the metadata of a component class and re-render all instances in place without refreshing the page. The function isn't used anywhere at the moment, but it will be necessary for future functionality.
PR Close#57953
Finalizes compiler implementation of the new `hydrate` triggers by:
* Reworking the logic that was depending on the `hydrateSpan` to distinguish hydrate triggers from non-hydrate triggers.
* Fixing that the `hydrate when` trigger didn't have a `hydrateSpan`.
* Adding an error if a parameter is passed into a `hydrate` trigger.
* Add an error if other `hydrate` triggers are used with `hydrate never`.
* Replacing the `prefetch` and `hydrate` flags in the template pipeline with a `modifiers` field.
* Fixing an error that was being thrown when reifying `hydrate` triggers in the pipeline.
* Adding quick info support for the `hydrate` keyword in the language service.
* Adding some tests for the new logic.
PR Close#57831
For component stylesheet hot module replacement scenarios, it will be necessarily to directly
encapsulate a component's stylesheet in a single operation. This currently requires the
consumer of the `encapsulateStyle` helper to use the internal Angular attribute values combined
with a find/replace over the entire stylesheet. To avoid both of these, the helper function now
has an optional second parameter which allows direct and full encapsulation of a style for a given
component when the component identifier is known.
PR Close#57809
Currently several parsing errors in the new control flow (e.g. missing `track` expression) produce errors whose span targets the entire block. This can be really noisy in the IDE where the error can span many lines in the template.
These changes switch to highlighting just the start of the block.
PR Close#57711
This commit updates a directive mock instance to include an extra field that a compiler code was expecting, which caused issues while processing elements with local refs and exported directives.
PR Close#57537
When disabling `i18nPreserveSignificantWhitespaceForLegacyExtraction` I was looking at a test case with ICU messages containing leading and trailing whitespace:
```angular
<div i18n>
{apples, plural, =other {I have many apples.}}
</div>
```
This would historically generate two messages:
```javascript
const MSG_TMP = goog.getMsg('{apples, plural, =other {I have many apples.}}');
const MSG_FOO = goog.getMsg(' {$ICU} ', { 'ICU': MSG_TMP });
```
But I found that I was getting just one message:
```javascript
const MSG_TMP = goog.getMsg(' {apples, plural, =other {I have many apples.}} ');
```
This is arguably an improvement, but changed the messages and message IDs, which isn't desirable with this option. I eventually traced this back to the `isIcu` initialization in [`i18n_parser.ts`](/packages/compiler/src/i18n/i18n_parser.ts):
```typescript
const context: I18nMessageVisitorContext = {
isIcu: nodes.length == 1 && nodes[0] instanceof html.Expansion,
// ...
};
```
[`_I18nVisitor.prototype.visitExpansion`](/packages/compiler/src/i18n/i18n_parser.ts) uses this to decide whether or not to generate a sub-message for a given ICU expansion:
```typescript
if (context.isIcu || context.icuDepth > 0) {
// Returns an ICU node when:
// - the message (vs a part of the message) is an ICU message, or
// - the ICU message is nested.
const expPh = context.placeholderRegistry.getUniquePlaceholder(`VAR_${icu.type}`);
i18nIcu.expressionPlaceholder = expPh;
context.placeholderToContent[expPh] = {
text: icu.switchValue,
sourceSpan: icu.switchValueSourceSpan,
};
return context.visitNodeFn(icu, i18nIcu);
}
// Else returns a placeholder
// ICU placeholders should not be replaced with their original content but with the their
// translations.
// TODO(vicb): add a html.Node -> i18n.Message cache to avoid having to re-create the msg
const phName = context.placeholderRegistry.getPlaceholderName('ICU', icu.sourceSpan.toString());
context.placeholderToMessage[phName] = this.toI18nMessage([icu], '', '', '', undefined);
const node = new i18n.IcuPlaceholder(i18nIcu, phName, icu.sourceSpan);
return context.visitNodeFn(icu, node);
```
Note that `isIcu` is the key condition between these two cases and depends on whether or not the ICU expansion has any siblings. The introduction of `WhitespaceVisitor` to `I18nMetaVisitor` trims insignificant whitespace, including empty text nodes not adjacent to an ICU expansion (from [`WhitespaceVisitor.prototype.visitText`](/packages/compiler/src/ml_parser/html_whitespaces.ts)):
```typescript
const isNotBlank = text.value.match(NO_WS_REGEXP);
const hasExpansionSibling =
context && (context.prev instanceof html.Expansion || context.next instanceof html.Expansion);
if (isNotBlank || hasExpansionSibling) {
// Transform node by trimming it...
return trimmedNode;
}
return null; // Drop node which is empty and has no ICU expansion sibling.
```
`hasExpansionSibling` was intended to retain empty text nodes leading or trailing an ICU expansion, however `context` was `undefined`, so this check failed and the leading / trailing text nodes were dropped. This resulted in trimming the ICU text by dropping the leading / trailing whitespace nodes. Having only a single ICU expansion with no leading / trailing text nodes caused `_I18nVisitor` to initialize `isIcu` incorrectly and caused it to generate one message instead of two.
`WhitespaceVisitor` is supposed to get this context from `visitAllWithSiblings`. So the fix here is to make sure `WhitespaceVisitor` is always visited via this function which provides the required context. I updated all usage sites to make sure this context is use consistently and implemented the `WhitespaceVisitor.prototype.visit` method to throw when the context is missing to make sure we don't encounter a similar mistake in the future.
Unfortunately this broke one compliance test. Specifically the [`icu_logic/icu_only.js`](/home/douglasparker/Source/ng/packages/compiler-cli/test/compliance/test_cases/r3_view_compiler_i18n/icu_logic/icu_only.js) test which changed from generating:
```javascript
function MyComponent_Template(rf, ctx) {
if (rf & 1) {
i0.ɵɵi18n(0, 0);
}
// ...
}
```
To now generating:
```javascript
function MyComponent_Template(rf, ctx) {
if (rf & 1) {
i0.ɵɵtext(0, " ");
i0.ɵɵi18n(1, 0);
i0.ɵɵtext(2, "\n");
}
// ...
}
```
This test uses the default value `preserveWhitespaces: false` (`i18nPreserveSignificantWhitespaceForLegacyExtraction` should not affect compiled JS output, we already retain significant whitespace there). So what this indicates to me is that ICU logic is already broken because it's not preserving significant whitespace in this case. My change is probably a bug fix, but one which would affect the compiled runtime, which is not in scope here. The root cause is because using `visitAllWithSiblings` everywhere means the context is retained correctly in this case and the whitespace is leading/trailing an ICU message, therefore it is retained per the logic of `WhitespaceVisitor.prototype.visitText` I mentioned eariler.
To address this, I left one usage of `WhitespaceVisitor` using `html.visitAll` instead of `visitAllWithSiblings` to retain this bug. I has to lossen the assertion I put in `WhitespaceVisitor.prototype.visit` to make this possible, but it should still throw by default when misused, which is the important part.
PR Close#56507
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
This commit adds an internal util method that allows to detect:
* which selectors are matching nodes in a template
* which pipes are present in a template
Both directives and pipes are split into 2 buckets: eagerly used and the ones that might potentially be defer-loaded.
PR Close#57466
Currently we use some short variable names like `t` and `r` in the generated factory functions. They can conflict with local symbols with the same names, if they're used for DI.
These changes rename the parameters to reduce the change for conflicts.
Fixes#57168.
PR Close#57181
Currently we use some short variable names like `t` and `r` in the generated factory functions. They can conflict with local symbols with the same names, if they're used for DI.
These changes add a `ɵ` to the generated variables to reduce the chance of conflicts.
Fixes#57168.
PR Close#57181
Enables the new `@let` syntax by default.
`@let` declarations are defined as:
1. The `@let` keyword.
2. Followed by one or more whitespaces.
3. Followed by a valid JavaScript name and zero or more whitespaces.
4. Followed by the `=` symbol and zero or more whitespaces.
5. Followed by an Angular expression which can be multi-line.
6. Terminated by the `;` symbol.
Example usage:
```
@let user = user$ | async;
@let greeting = user ? 'Hello, ' + user.name : 'Loading';
<h1>{{greeting}}</h1>
```
Fixes#15280.
PR Close#56715
These changes integrate let declarations into the template pipeline. This involves a few operations:
* Producing a `declareLet` instruction call at creation time to initialize the declaration.
* Producing a `storeLet` instruction call in the place of the let declaration, including the necessary `advance` calls beforehand.
* For let declarations used within their declaration view, moving the `const` to be placed right after the `storeLet` call to ensure the their value has been computed.
* For let declarations that are _only_ used in their declaration view, removing the `storeLet` call and inlining the expression into the constant statement.
PR Close#56299
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
Introduces a new `LetDeclaration` into the Render3 AST, simiarly to the HTML AST, and adds an initial integration into the various visitors.
PR Close#55848
Two-way bindings are meant to represent a property binding to an input and an event binding to an output, e.g. `[(ngModel)]="foo"` represents `[ngModel]="foo" (ngModelChange)="foo = $event"`. Previously due to a quirk in the template parser, we accidentally supported unassignable expressions in two-way bindings.
In #54154 the quirk was fixed, but we kept support or some common expression because of internal usages. Now the internal usages have been cleaned up so the backwards-compatibility code can be deleted.
Externally a migration was added in #54630 that will automatically fix any places that depended on the old behavior.
BREAKING CHANGE:
Angular only supports writable expressions inside of two-way bindings.
PR Close#55342
Previously the input flags were being generated as a reference to an enum member for better readability and under the assumption that minifiers would inline the values. That doesn't appear to be the case so these changes switch to using the literal values instead.
PR Close#55215
Adds logic to ingest the content of an `ng-content` element in the template type checker. We treat `ng-content` as a `ScopedNode`, because its content is inserted conditionally.
PR Close#54854
Based on some internal feedback, these changes add validations to prevent cases where the `@for` loop variable name is the same as one of the built-in context variables, or when one of the context variables is aliased to the same name as the item.
PR Close#55045
Builds on top of the previous changes to add support for deferred blocks during partial compilation. To do this, the following changes had to be made:
* The metadata passed into `ɵɵngDeclareComponent` has an additional field called `deferBlockDependencies` which has an array of the dependency loading functions for each defer block in the template. During linking, the dependency functions are loaded by matching their template index to the index in the `deferBlockDependencies` array.
* There's a new `ɵɵngDeclareClassMetadataAsync` function that is created for components that have deferred dependencies. It gets transpiled to `setClassMetadataAsync` and works in the same way by capturing a dependency loading function and setting the metadata after the dependencies are resolved. It also has some extra fields for capturing the version which are standard in linker-generated code.
* Deferred import statements are now stripped in partial compilation mode, similar to full compilation.
PR Close#54908
Adds the `ɵɵngDeclareClassMetadataAsync` function that will be produced during partial compilation for component classes that have deferred dependencies. At runtime the dependencies will be resolved before setting the metadata.
PR Close#54908
Updates the type of the resolver function to be any `Expression` since JIT may receive a function reference rather than a `ArrowFunctionExpr`.
PR Close#54908
Switches to tracking the deferred blocks in a flat array in the binder to ensure that their template order is maintained. This will be relevant in the next commits where we'll match deferred blocks by their index.
Note that the current map we have technically guarantees the insertion order in the spec, but the array is a bit more explicit.
PR Close#54908
Currently when aliasing a `for` loop variable with `let`, we replace the variable's old name with the new one. Since users have found this to be confusing, these changes switch to a model where the variable is available both under the original name and the new one.
Fixes#52528.
PR Close#54942
Moves the logic that creates the defer resolver function into `@angular/compiler` for consistency with the rest of the compilation APIs. Also renames some of the symbols to make it clearer what they're used for.
PR Close#54759
Currently we have the `deferrableDeclToImportDecl`, `deferBlocks`, `deferrableTypes` and `deferBlockDepsEmitMode` fields on the `R3ComponentMetadata` which is incorrect, because the interface is used both for JIT and AOT mode even though the information for those fields is AOT-specific. It will be problematic for partial compilation since the runtime will have a reference to the dependency loading function, but will not be able to provide any of the other information.
These changes make the following refactors:
1. It changes the defer-related information in `R3ComponentMetadata` to include only references to dependency functions which can be provided both in JIT and AOT.
2. Moves the AOT-specific defer analysis into the `ComponentResolutionData`.
3. Moves the construction the defer dependency function into the compilation phase of the `ComponentDecoratorHandler`.
4. Drops support for defer blocks from the `TemplateDefinitionBuilder`. This allows us to clean up some TDB-specific code and shouldn't have an effect on users since the TDB isn't used anymore.
PR Close#54759
`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
Currently we have the `deferrableDeclToImportDecl`, `deferBlocks`, `deferrableTypes` and `deferBlockDepsEmitMode` fields on the `R3ComponentMetadata` which is incorrect, because the interface is used both for JIT and AOT mode even though the information for those fields is AOT-specific. It will be problematic for partial compilation since the runtime will have a reference to the dependency loading function, but will not be able to provide any of the other information.
These changes make the following refactors:
1. It changes the defer-related information in `R3ComponentMetadata` to include only references to dependency functions which can be provided both in JIT and AOT.
2. Moves the AOT-specific defer analysis into the `ComponentResolutionData`.
3. Moves the construction the defer dependency function into the compilation phase of the `ComponentDecoratorHandler`.
4. Drops support for defer blocks from the `TemplateDefinitionBuilder`. This allows us to clean up some TDB-specific code and shouldn't have an effect on users since the TDB isn't used anymore.
PR Close#54700
This is based on an internal issue report.
An earlier change introduced a diagnostic to report cases where a symbol is in the `deferredImports` array, but is used eagerly. The check worked by looking through the deferred blocks in a scope, resolving the scope for each and checking if the element is within the scope. The problem is that resolving the scope won't work across scoped node boundaries. For example, if there's a control flow statement around the block or within the block but around the deferred dependency, it won't be able to resolve the scope since it isn't a direct child, e.g.
```
@if (true) {
@defer {
<deferred-dep/>
}
}
```
To fix this the case where the deferred block is inside a scoped node, I've changed the `R3BoundTarget.deferBlocks` to be a `Map` holding both the deferred block and its corresponding scope. Then to resolve the case where the dependency is within a scoped node inside the deferred block, I've added a depth-first traversal through the scopes within the deferred block.
PR Close#54499
Fixes that `ɵunwrapWritableSignal` inferring getter functions as not matching the interface of `WritableSignal` instead of preserving them.
PR Close#54252
In a previous commit the TCB was changed to cast the assignment to an input in order to widen its type to allow `WritableSignal`. This ended up breaking existing inputs whose setter has a wider type than its getter. These changes switch to unwrapping the value on the binding side.
PR Close#54252