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
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
Previously only the first branch of an `if` block was captured for content projection. This was done because of some planned refactors in the future. Since we've decided not to apply those refactors to conditionals, these changes update the compiler to capture each branch individually for content projection purposes.
PR Close#54921
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
Previously we assumed that if a `for` loop tracking function is in the form of `someMethod($index, $item)`, it will be pure so we didn't pass the parameter to bind the context to it. This appears to be risky, because we don't know if the method is trying to access `this`.
These changes play it safe by always binding method-based tracking functions.
Fixes#53628.
PR Close#54960
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
Kristiyan Kostadinov