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
Most of the specs in these tests are not relevant to Ivy:
//packages/compiler/test:test
//packages/compiler/test:test_web_chromium-local
However, a few test pieces of the compiler infrastructure that are used in
Ivy, and new BUILD.bazel files are created to separate them from the above
disabled targets:
//packages/compiler/test/css_parser:css_parser
//packages/compiler/test/css_parser:css_parser_web
//packages/compiler/test/expression_parser:expression_parser
//packages/compiler/test/expression_parser:expression_parser_web
//packages/compiler/test/ml_parser:ml_parser
//packages/compiler/test/ml_parser:ml_parser_web
//packages/compiler/test/selector:selector
//packages/compiler/test/selector:selector_web
PR Close#27301
