Follow-up from https://github.com/angular/angular/pull/61240#discussion_r2084445328. Adds a `isSelfClosing` property on element-like AST nodes so consumers can easily determine if it's self-closing, rather than having to look at the spans. This is useful for migrations and in the language service.
PR Close#61307
Switches the syntax for blocks from `{#block}{/block}` to `@block {}` based on the feedback from the community.
Read more about the decision-making process in our blog: https://blog.angular.io/meet-angulars-new-control-flow-a02c6eee7843
The existing block types changed in the following ways:
**Conditional blocks:**
```html
<!-- Before -->
{#if cond}
Main content
{:else if otherCond}
Else if content
{:else}
Else content
{/if}
<!-- After -->
@if (cond) {
Main content
} @else if (otherCond) {
Else if content
} @else {
Else content
}
```
**Deferred blocks**
```html
<!-- Before -->
{#defer when isLoaded}
Main content
{:loading} Loading...
{:placeholder} <icon>pending</icon>
{:error} Failed to load
{/defer}
<!-- After -->
@defer (when isLoaded) {
Main content
} @loading {
Loading...
} @placeholder {
<icon>pending</icon>
} @error {
Failed to load
}
```
**Switch blocks:**
```html
<!-- Before -->
{#switch value}
{:case 1}
One
{:case 2}
Two
{:default}
Default
{/switch}
<!-- After -->
@switch (value) {
@case (1) {
One
}
@case (2) {
Two
}
@default {
Default
}
}
```
**For loops**
```html
<!-- Before -->
{#for item of items; track item}
{{item.name}}
{:empty} No items
{/for}
<!-- After -->
@for (item of items; track item) {
{{item.name}}
} @empty {
No items
}
```
PR Close#51891
⚠️Disclaimer⚠️ this PR implements syntax that is still in an open RFC. It will be adjusted once the RFC is closed.
These changes implement the `BlockGroup` and `Block` AST nodes that will then be used to generate instructions based on the new syntax. A `BlockGroup` is a container for `Block` instances. The first block of a block is always implicit and required while any subsequent blocks are optional.
PR Close#50953
After updating to a more recent version of rollup, rollup started to
complain because the `TreeParseResult` class is being re-exported
twice in the `index.ts -> public-api.ts -> compiler.ts` entry-point.
Rollup threw errors like:
```
Error: "ParseTreeResult" cannot be exported from
<..>/ml_parser/parser.mjs as it is a re-export that references itself.
```
It seems like Rollup ideally would not throw here, similar to TypeScript
which detects that these exports are the same and just dedupes them, but
it's low-effort fixing this for now and actually is a good opportunity
to make the public API a little more easy understand (when looking at
the `compiler.ts` file).
PR Close#43431
The tests were checking that the source-span of parsed HTML nodes were
accurate, but they were not checking the span when it includes the
"leading trivia", which are given by the `fullStart` rather than `start`
location.
PR Close#43132
When it was tokenized, text content is split into parts that can include
interpolations and encoded entities tokens.
To make this information available to downstream processing, this commit
adds these tokens to the `Text` AST nodes, with suitable processing.
PR Close#43132
The tests were checking that the source-span of parsed HTML nodes were
accurate, but they were not checking the span when it includes the
"leading trivia", which are given by the `fullStart` rather than `start`
location.
PR Close#42062
When it was tokenized, text content is split into parts that can include
interpolations and encoded entities tokens.
To make this information available to downstream processing, this commit
adds these tokens to the `Text` AST nodes, with suitable processing.
PR Close#42062
Previously, the `startSourceSpan` property could be null
but in reality it is always well defined - except for a legacy
case in the old i18n extraction/merging code, where the
typings for source-spans are already being undermined.
Making this property non-null, simplifies code elsewhere
in the project.
PR Close#38581
HTML is very lenient when it comes to closing elements, so Angular's parser has
rules that specify which elements are implicitly closed when closing a tag.
The parser keeps track of the nesting of tag names using a stack and parsing
a closing tag will pop as many elements off the stack as possible, provided
that the elements can be implicitly closed.
For example, consider the following templates:
- `<div><br></div>`, the `<br>` is implicitly closed when parsing `</div>`,
because `<br>` is a void element.
- `<div><p></div>`, the `<p>` is implicitly closed when parsing `</div>`,
as `<p>` is allowed to be closed by the closing of its parent element.
- `<ul><li>A <li>B</ul>`, the first `<li>` is implicitly closed when parsing
the second `<li>`, whereas the second `<li>` would be implicitly closed when
parsing the `</ul>`.
In all the cases above the parsed structure would be correct, however the source
span of the closing `</div>` would incorrectly be assigned to the element that
is implicitly closed. The problem was that closing an element would associate
the source span with the element at the top of the stack, however this may not
be the element that is actually being closed if some elements would be
implicitly closed.
This commit fixes the issue by assigning the end source span with the element
on the stack that is actually being closed. Any implicitly closed elements that
are popped off the stack will not be assigned an end source span, as the
implicit closing implies that no ending element is present.
Note that there is a difference between self-closed elements such as `<input/>`
and implicitly closed elements such as `<input>`. The former does have an end
source span (identical to its start source span) whereas the latter does not.
Fixes#36118
Resolves FW-2004
PR Close#38126
