parse constructions like `:where(:host-context(.foo))` correctly
revert logic which lead to decreased specificity if `:where` was applied
to another selector, for example `div` is transformed to `div[contenta]`
with specificity of (0,1,1) so `div:where(.foo)` should not decrease it
leading to `div[contenta]:where(.foo)` with the same specificity (0,1,1)
instead of `div:where(.foo[contenta])` with specificity equal to (0,0,1)
PR Close#57796
add support for nested and deeply nested (up to three levels) selectors,
parse multiple :host selectors, scope selectors within pseudo functions
PR Close#57796
allow css combinators within pseudo selector functions, parsing those
correctly. Similarly to previous version, don't break selectors
into part if combinators are within parenthesis, for example
`:where(.one > .two)`
PR Close#57796
fix scoping and transforming logic of the `shimCssText` for the
components with encapsulated view:
- add support for pseudo selector functions
- apply content scoping for inner selectors of `:is()` and `:where()`
- allow multiple comma separated selectors inside pseudo selectors
Fixes#45686
PR Close#57796
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
Some Angular template instructions that follow each other may be chained
together in a single expressions statement, containing a deeply nested
AST of call expressions. The number of chained instructions wasn't previously
limited, so this could result in very deep ASTs that cause stack overflow
errors during TypeScript emit.
This commit introduces a limit to the number of chained instructions to
avoid these problems.
Closes#57066
PR Close#57069
Fixes that the runtime implementation of `ɵɵngDeclareDirective` was interpreting the `hostDirectives` mapping incorrectly. Instead of treating the inputs/outputs as `['binding', 'alias']` arrays, it was parsing them as `['binding: alias']`. This was leading to runtime errors if a user is consuming a partially-compiled library in JIT mode.
Fixes#54096.
PR Close#57002
Replace loose equality (==) with strict equality (===) for the 'code' variable.
This change ensures type safety and prevents unintended type coercion.
PR Close#56944
It is valid CSS to list keyframe names in an animation declaration only
separating the names with a comma and no whitespace. This is typical of
production builds. Updated a couple of regexes and added a couple of
tests to account for this scenario.
Fixes#53038
PR Close#56800
Currently the logic that maps a name to a variable looks at the variables in their definition order. This means that `@let` declarations from parent views will always come before local ones, because the local ones are declared inline whereas the parent ones are hoisted to the top of the function.
These changes resolve the issue by giving precedence to the local variables.
Fixes#56737.
PR Close#56752
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
Adds the implementation of the following new instructions:
* `declareLet` - creation-time instruction that initializes the slot for a let declaration.
* `storeLet` - update-time instruction that stores the current value of a let declaration.
* `readContextLet` - instruction that reads the stored value of a let declaration from a different view.
On top of the instructions, it also introduces a new `LetDeclaration` TNode type.
The new TNode is nececessary for DI to work correctly in pipes inside the let expression,
as well as for proper hydration support.
PR Close#56527
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
Whenever we parse object property assignment shorthands in expression
ASTs, the AST will have no information about whether the property read
for the `LiteralMap` is built based on the shorthand or not.
Exposing this information in the AST is useful for migrations as those
might need to decompose the shorthand into its longer form to e.g.
invoke a signal read.
PR Close#56405
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
Currently we optimize methods that pass both `$index` and the item into a method. We can take this a step further by also optimizing calls that only pass `$index` into the first parameter.
PR Close#55872
Since we aren't using clang anymore, we can remove the comments and the workarounds that were in place to prevent it from doing the wrong thing.
PR Close#55750
Currently the variable optimization phase happens somewhat late in the process which is okay since the variables are generally static (e.g. `reference()` instruction calls). In some upcoming work we'll have variables that consume slots and require `advance` instructions. To allow for them to be optimized correctly, we need to move the variable optimization phase earlier, at least before we allocate the slots.
PR Close#55771
Previously, multiline selectors were being converted into single lines, resulting in sourcemap disruptions due to shifts in line numbers.
Closes#55508
PR Close#55509
Fixes that we didn't have the MathML elements in the schema. Note that we can't discover which tag names are available by looking at globally-available classes, because all MathML elements are `MathMLElement` rather than something like `SVGCircleElement`. As such, I ended up having to hardcode the currently-available tags.
Fixes#55608.
PR Close#55631
Currently fallback content for `ng-content` gets declared and rendered out in one go. This breaks down if multiple instances of the same component are used where one doesn't render the fallback content while the other one does, because the `TNode` for the content has to be created during the first creation pass.
These changes resolve the issue by always _declaring_ the template, but only rendering it if the slot is empty.
Fixes#55466.
PR Close#55478
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
This reverts commit 367b3ee6e9.
The search element is not a void element but existing components may use
the same selector and be used as a void element.
PR Close#55127
