When parsing for i18n messages, interpolated strings are
split into `Text` and `Placeholder` pieces. The method that
does this `_visitTextWithInterpolation()` was becoming too
complex. This commit refactors that method along with some
associated functions that it uses.
PR Close#39717
This commit handles the following cases:
- incomplete pipes in a pipe chain
- incomplete arguments in a pipe chain
- incomplete arguments provided to a pipe
- nested pipes
The idea is to unconditionally recover on the presence of a pipe, which
should be okay because expression parsing can be independently between
pipes.
PR Close#39437
There is no actionable change in this commit other than to pretty-print
EOF tokens. Actual parsing of unterminated pipes is already supported,
this just adds a test for it.
Part of #38596
PR Close#39113
The expression parser already has support for recovering on malformed
property reads, but did not have tests describing the recovered ast in
such cases. This commit adds tests to demonstrate such cases; in
particular, the recovered ast is a full PropertyRead but with an empty
property name. This is likely the most preferred option, as it does not
constrain consumers of the AST to what the property name should look
like. Furthermore, we cannot mark the property name as empty in any
other way (e.g. an EmptyExpr) because the property name, as of present,
is a string field rather than an AST itself.
Note that tokens past a malformed property read are not preserved in the
AST (for example in `foo.1234`, `1234` is not preserved in the AST).
This is because the extra tokens do not belong to the singular
expression created by the property read, and there is not a meaningful
way to interpret a secondary expression in a single parsed expression.
Part of #38596
PR Close#38998
This patch refactors the interpolation parser to do so iteratively
rather than using a regex. Doing so prepares us for supporting granular
recovery on poorly-formed interpolations, for example when an
interpolation does not terminate (`{{ 1 + 2`) or is not terminated
properly (`{{ 1 + 2 {{ 2 + 3 }}`).
Part of #38596
PR Close#38977
This patch adds support for recovering well-formed (and near-complete)
ASTs for semantically malformed keyed reads and keyed writes. See the
added tests for details on the types of semantics we can now recover;
in particular, notice that some assumptions are made about the form of
a keyed read/write intended by a user. For example, in the malformed
expression `a[1 + = 2`, we assume that the user meant to write a binary
expression for the key of `a`, and assign that key the value `2`. In
particular, we now parse this as `a[1 + <empty expression>] = 2`. There
are some different interpretations that can be made here, but I think
this is reasonable.
The actual changes in the parser code are fairly minimal (a nice
surprise!); the biggest addition is a `writeContext` that marks whether
the `=` operator can serve as a recovery point after error detection.
Part of #38596
PR Close#39004
Prior to this change, the unary + and - operators would be parsed as `x - 0`
and `0 - x` respectively. The runtime semantics of these expressions are
equivalent, however they may introduce inaccurate template type checking
errors as the literal type is lost, for example:
```ts
@Component({
template: `<button [disabled]="isAdjacent(-1)"></button>`
})
export class Example {
isAdjacent(direction: -1 | 1): boolean { return false; }
}
```
would incorrectly report a type-check error:
> error TS2345: Argument of type 'number' is not assignable to parameter
of type '-1 | 1'.
Additionally, the translated expression for the unary + operator would be
considered as arithmetic expression with an incompatible left-hand side:
> error TS2362: The left-hand side of an arithmetic operation must be of
type 'any', 'number', 'bigint' or an enum type.
To resolve this issues, the implicit transformation should be avoided.
This commit adds a new unary AST node to represent these expressions,
allowing for more accurate type-checking.
Fixes#20845Fixes#36178
PR Close#37918
Builds on top of #34655 to support more cases that could be using a pipe inside host bindings (e.g. ternary expressions or function calls).
Fixes#37610.
PR Close#37883
ASTs for property read and method calls contain information about
the entire span of the expression, including its receiver. Use cases
like a language service and compile error messages may be more
interested in the span of the direct identifier for which the
expression is constructed (i.e. an accessed property). To support this,
this commit adds a `nameSpan` property on
- `PropertyRead`s
- `SafePropertyRead`s
- `PropertyWrite`s
- `MethodCall`s
- `SafeMethodCall`s
The `nameSpan` property already existed for `BindingPipe`s.
This commit also updates usages of these expressions' `sourceSpan`s in
Ngtsc and the langauge service to use `nameSpan`s where appropriate.
PR Close#36826
This commit adds fine-grained text spans to TemplateBinding for microsyntax expressions.
1. Source span
By convention, source span refers to the entire span of the binding,
including its key and value.
2. Key span
Span of the binding key, without any whitespace or keywords like `let`
The value span is captured by the value expression AST.
This is part of a series of PRs to fix source span mapping in microsyntax expression.
For more info, see the doc https://docs.google.com/document/d/1mEVF2pSSMSnOloqOPQTYNiAJO0XQxA1H0BZyESASOrE/edit?usp=sharing
PR Close#35897
Currently, template expressions and statements have their location
recorded relative to the HTML element they are in, with no handle to
absolute location in a source file except for a line/column location.
However, the line/column location is also not entirely accurate, as it
points an entire semantic expression, and not necessarily the start of
an expression recorded by the expression parser.
To support record of the source code expressions originate from, add a
new `sourceSpan` field to `ASTWithSource` that records the absolute byte
offset of an expression within a source code.
Implement part 2 of [refactoring template parsing for
stability](https://hackmd.io/@X3ECPVy-RCuVfba-pnvIpw/BkDUxaW84/%2FMA1oxh6jRXqSmZBcLfYdyw?type=book).
PR Close#31391
A long time ago Angular used to support both those attribute notations:
- `*attr='binding'`
- `template=`attr: binding`
Because the last notation has been dropped we can refactor the binding parsing.
Source maps will benefit from that as no `attr:` prefix is added artificialy any
more.
PR Close#23460
Template expressions can now use a post-fix `!` operator
that asserts the target of the operator is not null. This is
similar to the TypeScript non-null assert operator. Expressions
generated in factories will be generated with the non-null assert
operator.
Closes: #10855
* feat(common): support `as` syntax in template/* bindings
Closes#15020
Showing the new and the equivalent old syntax.
- `*ngIf="exp as var1”`
=> `*ngIf="exp; let var1 = ngIf”`
- `*ngFor="var item of itemsStream |async as items”`
=> `*ngFor="var item of itemsStream |async; let items = ngForOf”`
* feat(common): convert ngIf to use `*ngIf="exp as local“` syntax
* feat(common): convert ngForOf to use `*ngFor=“let i of exp as local“` syntax
* feat(common): expose NgForOfContext and NgIfContext
Pete Bacon Darwin
ayazhafiz
JoostK
crisbeto
Joey Perrott
Alex Rickabaugh
Keen Yee Liau
Victor Berchet
Trotyl
Misko Hevery
Chuck Jazdzewski
Jason Aden