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
The html parser already normalizes line endings (converting `\r\n` to `\n`)
for most text in templates but it was missing the expressions of ICU expansions.
In ViewEngine backticked literal strings, used to define inline templates,
were already normalized by the TypeScript parser.
In Ivy we are parsing the raw text of the source file directly so the line
endings need to be manually normalized.
This change ensures that inline templates have the line endings of ICU
expression normalized correctly, which matches the ViewEngine.
In ViewEngine external templates, defined in HTML files, the behavior was
different, since TypeScript was not normalizing the line endings.
Specifically, ICU expansion "expressions" are not being normalized.
This is a problem because it means that i18n message ids can be different on
different machines that are setup with different line ending handling,
or if the developer moves a template from inline to external or vice versa.
The goal is always to normalize line endings, whether inline or external.
But this would be a breaking change since it would change i18n message ids
that have been previously computed. Therefore this commit aligns the ivy
template parsing to have the same "buggy" behavior for external templates.
There is now a compiler option `i18nNormalizeLineEndingsInICUs`, which
if set to `true` will ensure the correct non-buggy behavior. For the time
being this option defaults to `false` to ensure backward compatibility while
allowing opt-in to the desired behavior. This option's default will be
flipped in a future breaking change release.
Further, when this option is set to `false`, any ICU expression tokens,
which have not been normalized, are added to the `ParseResult` from the
`HtmlParser.parse()` method. In the future, this collection of tokens could
be used to diagnose and encourage developers to migrate their i18n message
ids. See FW-2106.
Closes#36725
PR Close#36741
Previously, an expansion case could only start with an alpha numeric character.
This commit fixes this by allowing an expansion case to start with any character
except `}`.
The [ICU spec](http://userguide.icu-project.org/formatparse/messages) is pretty vague:
> Use a "select" argument to select sub-messages via a fixed set of keywords.
It does not specify what can be a "keyword" but from looking at the surrounding syntax it
appears that it can indeed be any string that does not contain a `}` character.
Closes#31586
PR Close#36123
BREAKING CHANGE:
Certain elements (like `<tr>` or `<col>`) require parent elements to be of a certain type by the HTML specification
(ex. <tr> can only be inside <tbody> / <thead>). Before this change Angular template parser was auto-correcting
"invalid" HTML using the following rules:
- `<tr>` would be wrapped in `<tbody>` if not inside `<tbody>`, `<tfoot>` or `<thead>`;
- `<col>` would be wrapped in `<colgroup>` if not inside `<colgroup>`.
This meachanism of automatic wrapping / auto-correcting was problematic for several reasons:
- it is non-obvious and arbitrary (ex. there are more HTML elements that has rules for parent type);
- it is incorrect for cases where `<tr>` / `<col>` are at the root of a component's content, ex.:
```html
<projecting-tr-inside-tbody>
<tr>...</tr>
</projecting-tr-inside-tbody>
```
In the above example the `<projecting-tr-inside-tbody>` component culd be "surprised" to see additional
`<tbody>` elements inserted by Angular HTML parser.
PR Close#29219
When tokenizing markup (e.g. HTML) element attributes
can have quoted or unquoted values (e.g. `a=b` or `a="b"`).
The `ATTR_VALUE` tokens were capturing the quotes, which
was inconsistent and also affected source-mapping.
Now the tokenizer captures additional `ATTR_QUOTE` tokens,
which the HTML related parsers understand and factor into their
token parsing.
PR Close#28055
This commit consolidates the options that can modify the
parsing of text (e.g. HTML, Angular templates, CSS, i18n)
into an AST for further processing into a single `options`
hash.
This makes the code cleaner and more readable, but also
enables us to support further options to parsing without
triggering wide ranging changes to code that should not
be affected by these new options. Specifically, it will let
us pass information about the placement of a template
that is being parsed in its containing file, which is essential
for accurate SourceMap processing.
PR Close#28055
BREAKING CHANGE:
The `<template>` tag was deprecated in Angular v4 to avoid collisions (i.e. when
using Web Components).
This commit removes support for `<template>`. `<ng-template>` should be used
instead.
BEFORE:
<!-- html template -->
<template>some template content</template>
# tsconfig.json
{
# ...
"angularCompilerOptions": {
# ...
# This option is no more supported and will have no effect
"enableLegacyTemplate": [true|false]
}
}
AFTER:
<!-- html template -->
<ng-template>some template content</ng-template>
PR Close#22783
JoostK
Joey Perrott
Pete Bacon Darwin
Alex Rickabaugh
Sonu Kapoor
Pawel Kozlowski
Victor Berchet
Misko Hevery
Olivier Combe
Trotyl Yu
Dzmitry Shylovich
Jason Aden