Consider a template with a context variable `a`:
```
<ng-template let-a>{{this.a}}</ng-template>
```
t push -fAn interpolation inside that template to `this.a` should intuitively read the class variable `a`. However, today, it refers to the context variable `a`, both in the TCB and the generated code.
In this commit, the above interpolation now refers to the class field `a`.
BREAKING CHANGE: `this.foo` property reads no longer refer to template context variables. If you intended to read the template variable, do not use `this.`.
Fixes#55115
PR Close#55183
This commit updates a directive mock instance to include an extra field that a compiler code was expecting, which caused issues while processing elements with local refs and exported directives.
PR Close#57537
When disabling `i18nPreserveSignificantWhitespaceForLegacyExtraction` I was looking at a test case with ICU messages containing leading and trailing whitespace:
```angular
<div i18n>
{apples, plural, =other {I have many apples.}}
</div>
```
This would historically generate two messages:
```javascript
const MSG_TMP = goog.getMsg('{apples, plural, =other {I have many apples.}}');
const MSG_FOO = goog.getMsg(' {$ICU} ', { 'ICU': MSG_TMP });
```
But I found that I was getting just one message:
```javascript
const MSG_TMP = goog.getMsg(' {apples, plural, =other {I have many apples.}} ');
```
This is arguably an improvement, but changed the messages and message IDs, which isn't desirable with this option. I eventually traced this back to the `isIcu` initialization in [`i18n_parser.ts`](/packages/compiler/src/i18n/i18n_parser.ts):
```typescript
const context: I18nMessageVisitorContext = {
isIcu: nodes.length == 1 && nodes[0] instanceof html.Expansion,
// ...
};
```
[`_I18nVisitor.prototype.visitExpansion`](/packages/compiler/src/i18n/i18n_parser.ts) uses this to decide whether or not to generate a sub-message for a given ICU expansion:
```typescript
if (context.isIcu || context.icuDepth > 0) {
// Returns an ICU node when:
// - the message (vs a part of the message) is an ICU message, or
// - the ICU message is nested.
const expPh = context.placeholderRegistry.getUniquePlaceholder(`VAR_${icu.type}`);
i18nIcu.expressionPlaceholder = expPh;
context.placeholderToContent[expPh] = {
text: icu.switchValue,
sourceSpan: icu.switchValueSourceSpan,
};
return context.visitNodeFn(icu, i18nIcu);
}
// Else returns a placeholder
// ICU placeholders should not be replaced with their original content but with the their
// translations.
// TODO(vicb): add a html.Node -> i18n.Message cache to avoid having to re-create the msg
const phName = context.placeholderRegistry.getPlaceholderName('ICU', icu.sourceSpan.toString());
context.placeholderToMessage[phName] = this.toI18nMessage([icu], '', '', '', undefined);
const node = new i18n.IcuPlaceholder(i18nIcu, phName, icu.sourceSpan);
return context.visitNodeFn(icu, node);
```
Note that `isIcu` is the key condition between these two cases and depends on whether or not the ICU expansion has any siblings. The introduction of `WhitespaceVisitor` to `I18nMetaVisitor` trims insignificant whitespace, including empty text nodes not adjacent to an ICU expansion (from [`WhitespaceVisitor.prototype.visitText`](/packages/compiler/src/ml_parser/html_whitespaces.ts)):
```typescript
const isNotBlank = text.value.match(NO_WS_REGEXP);
const hasExpansionSibling =
context && (context.prev instanceof html.Expansion || context.next instanceof html.Expansion);
if (isNotBlank || hasExpansionSibling) {
// Transform node by trimming it...
return trimmedNode;
}
return null; // Drop node which is empty and has no ICU expansion sibling.
```
`hasExpansionSibling` was intended to retain empty text nodes leading or trailing an ICU expansion, however `context` was `undefined`, so this check failed and the leading / trailing text nodes were dropped. This resulted in trimming the ICU text by dropping the leading / trailing whitespace nodes. Having only a single ICU expansion with no leading / trailing text nodes caused `_I18nVisitor` to initialize `isIcu` incorrectly and caused it to generate one message instead of two.
`WhitespaceVisitor` is supposed to get this context from `visitAllWithSiblings`. So the fix here is to make sure `WhitespaceVisitor` is always visited via this function which provides the required context. I updated all usage sites to make sure this context is use consistently and implemented the `WhitespaceVisitor.prototype.visit` method to throw when the context is missing to make sure we don't encounter a similar mistake in the future.
Unfortunately this broke one compliance test. Specifically the [`icu_logic/icu_only.js`](/home/douglasparker/Source/ng/packages/compiler-cli/test/compliance/test_cases/r3_view_compiler_i18n/icu_logic/icu_only.js) test which changed from generating:
```javascript
function MyComponent_Template(rf, ctx) {
if (rf & 1) {
i0.ɵɵi18n(0, 0);
}
// ...
}
```
To now generating:
```javascript
function MyComponent_Template(rf, ctx) {
if (rf & 1) {
i0.ɵɵtext(0, " ");
i0.ɵɵi18n(1, 0);
i0.ɵɵtext(2, "\n");
}
// ...
}
```
This test uses the default value `preserveWhitespaces: false` (`i18nPreserveSignificantWhitespaceForLegacyExtraction` should not affect compiled JS output, we already retain significant whitespace there). So what this indicates to me is that ICU logic is already broken because it's not preserving significant whitespace in this case. My change is probably a bug fix, but one which would affect the compiled runtime, which is not in scope here. The root cause is because using `visitAllWithSiblings` everywhere means the context is retained correctly in this case and the whitespace is leading/trailing an ICU message, therefore it is retained per the logic of `WhitespaceVisitor.prototype.visitText` I mentioned eariler.
To address this, I left one usage of `WhitespaceVisitor` using `html.visitAll` instead of `visitAllWithSiblings` to retain this bug. I has to lossen the assertion I put in `WhitespaceVisitor.prototype.visit` to make this possible, but it should still throw by default when misused, which is the important part.
PR Close#56507
This configures whether or not to preserve whitespace content when extracting messages from Angular templates in the legacy (View Engine) extraction pipeline.
This includes several bug fixes which unfortunately cannot be landed without changing message IDs in a breaking fashion and are necessary to properly trim whitespace. Instead these bug fixes are included only when the new flag is disabled.
PR Close#56507
This commit adds an internal util method that allows to detect:
* which selectors are matching nodes in a template
* which pipes are present in a template
Both directives and pipes are split into 2 buckets: eagerly used and the ones that might potentially be defer-loaded.
PR Close#57466
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
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
`TemplateDefinitionBuilder` is the legacy template compiler, and was replaced by Template Pipeline as the default in v17.3.
This PR attempts to delete `TemplateDefinitionBuilder`, `ExpressionConverter`, and various helpers (i18n context, style builder, property visitors, etc).
Consider this a first pass: a lot of code has not yet been deleted (e.g. old TDB-specific test cases), and I'm sure I have missed additional helper code.
PR Close#54757
These changes expose the `ngContentSelectors` and `preserveWhitespaces` metadata to the TCB so they can be used in the next commit to implement a new diagnostic.
PR Close#53190
When blocks were initially implemented, they were represented as containers in the i18n AST. This is problematic, because block affect the structure of the message.
These changes introduce a new `BlockPlaceholder` AST node and integrate it into the i18n pipeline. With the new node blocks are represented with the `START_BLOCK_<name>` and `CLOSE_BLOCK_<name>` placeholders.
PR Close#52958
These changes expose the `ngContentSelectors` and `preserveWhitespaces` metadata to the TCB so they can be used in the next commit to implement a new diagnostic.
PR Close#52726
Adds some logic to skip over comments when resolving implicit `@defer` block triggers. This currently isn't a problem since we don't capture comments by default, but it may come up if we start capturing comments.
PR Close#52449
Enables the new `@` block syntax by default by removing the `enabledBlockTypes` flags. There are still some internal flags that allow special use cases to opt out of the block syntax, like during XML parsing and when compiling older libraries (see #51979).
PR Close#51994
Adds support for defining `viewport`, `interaction` and `hover` triggers with no parameters. If the framework encounters such a case, it resolves the trigger to the root element of the `@placeholder` block. Triggers with no parameters have the following restrictions:
1. They have to be placed on an `@defer` block that has an `@placeholder`.
2. The `@placeholder` can only have one root node.
3. The root placeholder node has to be an element.
PR Close#51922
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
Adds a utility to the `BoundTarget` that helps with resolving which element a deferred block is pointing to. We need a separate method for this, because deferred blocks have some special logic for where the trigger can be located.
PR Close#51816
When the `TargetBinder` was written, the only embedded-view-based nodes were templates, but now we have `{#if}`, `{#switch}` and `{#defer}` which have similar semantics. These changes rework the binder to account for the new nodes.
PR Close#51816
Fixes that if a directive/pipe is used after a nested `defer` block, we weren't tracking it as lazy anymore. This was due to the fact that we were resetting the `isInDeferBlock` to false every time instead of the previous value.
PR Close#51262
This commit updates the logic of the TemplateBinder and DirectiveBinder classes to recognize defer blocks. The logic is updated to prevent Directive and Pipe matching inside the defer block. Instead, the scope for those blocks would be calculated separately.
PR Close#51162
Change sourceSpan for Comment nodes to cover the whole comment
instead of just the opening token.
The primary motivation for this is the interaction between ESLint and
`@angular-eslint`. ESLint can detect unused `eslint-disable` directives
in comments and automatically remove them when running with `--fix`.
This is based on ranges computed from AST spans, and as a result
does not work inside Angular templates - right now all comments
claim to be 4 characters long so only the opening `<!--` is removed.
PR Close#50855
Adds the logic to create `defer`-specific AST nodes from the generic HTML `BlockGroup` and `Block`. The logic for parsing the triggers will be in the next commit.
PR Close#51050
Fixes that the compiler was matching directives based on `attr` bindings which doesn't correspond to the runtime behavior. This wasn't a problem until now because the matched directives would basically be a noop, but they can cause issues with required inputs.
PR Close#49713
This is the compile-time implementation of the `hostDirectives` feature plus a little bit of runtime code to illustrate how the newly-generated code will plug into the runtime. It works by creating a call to the new `ɵɵHostDirectivesFeature` feature whenever a directive has a `hostDirectives` field. Afterwards `ɵɵHostDirectivesFeature` will patch a new function onto the directive definition that will be invoked during directive matching.
For example, if we take the following definition:
```ts
@Directive({
hostDirectives: [HostA, {directive: HostB, inputs: ['input: alias']}]
})
class MyDir {}
```
Will compile to:
```js
MyDir.ɵdir = ɵɵdefineComponent({
features: [ɵɵHostDirectivesFeature([HostA, {
directive: HostB,
inputs: {
input: "alias"
}
}])]
});
```
The template type checking is implemented during directive matching by adding the host directives applied on the host to the array of matched directives whenever the host is matched in a template.
Relates to #8785.
PR Close#46868
When parsing interpolations, the input string is _decoded_ from what was
in the orginal template. This means that we cannot soley rely on the input
string to compute source spans because it does not necessarily reflect
the exact content of the original template. Specifically, when there is
an HTML entity (i.e. ` `), this will show up in its decoded form
when processing the interpolation (' '). We need to compute offsets
using the original _encoded_ string.
Note that this problem only surfaces in the splitting of interpolations.
The spans to this point have already been tracked accurately. For
example, given the template ` <div></div>`, the source span for the
`div` is already correctly determined to be 6. Only when we encounter
interpolations with many parts do we run into situations where we need
to compute new spans for the individual parts of the interpolation.
PR Close#44811
Refs http://b/214103351.
This happens if a user writes `<span i18n>Message</span>`. This is accepted as an internationalized message, but without a description. JSCompiler will throw an error in this situation because descriptions are generally required. Now, the Angular compiler will generate a suppression annotation so JSCompiler allows the syntax. This will ease an internal migration to JSCompiler-based i18n.
PR Close#44787
In `language-service`, the `checker.getDirectiveMetadata` doesn't return the animations meta of the `Component`.
but it's useful for animation completion.
PR Close#44630
This commit finishes the removal of View Engine from the codebase, deleting
those pieces of @angular/compiler which were only used for VE.
Co-Authored-By: JoostK <joost.koehoorn@gmail.com>
PR Close#44368
This commit removes most tests that were designated as only covering View
Engine code. It also removes tag filters from CI and local commands to run
tests.
In a few cases (such as with the packages/compiler tests), this tag was
improperly applied, and certain test cases have been added back running in
Ivy mode.
This commit also empties `@angular/compiler/testing` as it is no longer
necessary (this is safe since compiler packages are not public API). It can
be deleted in the future.
PR Close#43884
When extracting i18n messages from templates, ICU messages are split out from the
message that contains them. This can make it difficult in the translation files to match up
the two messages, especially if the ICU is reused in multiple placeholders.
This commit builds on top of the previous one to expose the message ID of ICU messages
from the ICU placeholders as additional metadata in the `$localize` tagged strings.
Now the metablock following any placeholder can also contain the associated ID
delimited from the placeholder name by `@@`.
Fixes#17506
PR Close#43534
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
Previously, the way templates were tokenized meant that we lost information
about the location of interpolations if the template contained encoded HTML
entities. This meant that the mapping back to the source interpolated strings
could be offset incorrectly.
Also, the source-span assigned to an i18n message did not include leading
whitespace. This confused the output source-mappings so that the first text
nodes of the message stopped at the first non-whitespace character.
This commit makes use of the previous refactorings, where more fine grain
information was provided in text tokens, to enable the parser to identify
the location of the interpolations in the original source more accurately.
Fixes#41034
PR Close#43132
Previously, the way templates were tokenized meant that we lost information
about the location of interpolations if the template contained encoded HTML
entities. This meant that the mapping back to the source interpolated strings
could be offset incorrectly.
Also, the source-span assigned to an i18n message did not include leading
whitespace. This confused the output source-mappings so that the first text
nodes of the message stopped at the first non-whitespace character.
This commit makes use of the previous refactorings, where more fine grain
information was provided in text tokens, to enable the parser to identify
the location of the interpolations in the original source more accurately.
Fixes#41034
PR Close#42062
Adds a `collectCommentNodes` option on `ParseTemplateOptions` which will cause the returned `ParsedTemplate` to include an array of all html comments found in the template.
PR Close#41251
If the template parse option `leadingTriviaChars` is configured to
consider whitespace as trivia, any trailing whitespace of an element
would be considered as leading trivia of the subsequent element, such
that its `start` span would start _after_ the whitespace. This means
that the start span cannot be used to mark the end of the current
element, as its trailing whitespace would then be included in its span.
Instead, the full start of the subsequent element should be used.
To harden the tests that for the Ivy parser, the test utility `parseR3`
has been adjusted to use the same configuration for `leadingTriviaChars`
as would be the case in its production counterpart `parseTemplate`. This
uncovered another bug in offset handling of the interpolation parser,
where the absolute offset was computed from the start source span
(which excludes leading trivia) whereas the interpolation expression
would include the leading trivia. As such, the absolute offset now also
uses the full start span.
Fixes#39148
PR Close#40513
Now when the animation trigger output event is missing its phase value name, the `BoundEvent` will be ignored,
but it's useful for completion in language service.
PR Close#39925
This commit introduces an `isStructural` flag on directive metadata, which
is `true` if the directive injects `TemplateRef` (and thus is at least
theoretically usable as a structural directive). The flag is not used for
anything currently, but will be utilized by the Language Service to offer
better autocompletion results for structural directives.
PR Close#40032
Tokenized text node may have leading whitespace skipped from their
source-span. But the source-span is used to compute where there are
interpolated blocks, resulting in placeholder nodes whose source-spans
are offset by the amount of skipped characters.
This fix uses the `fullStart` location of text source-spans for computing
the source-span of placeholders, so that they are accurate.
Fixes#39195
PR Close#39486
In an i18n message, two placeholders next to each other must have
an "empty" message-part to separate them. Previously, the source-span
for this message-part was pointing to the wrong original location.
This caused problems in the generated source-maps and lead to extracted
i18n messages from being rendered incorrectly.
PR Close#39486
This commit updates the symbols in the TemplateTypeCheck API and methods
for retrieving them:
* Include `isComponent` and `selector` for directives so callers can determine which
attributes on an element map to the matched directives.
* Add a new `TextAttributeSymbol` and return this when requesting a symbol for a `TextAttribute`.
* When requesting a symbol for `PropertyWrite` and `MethodCall`, use the
`nameSpan` to retrieve symbols.
* Add fix to retrieve generic directives attached to elements/templates.
PR Close#38844
Using an interface makes the code cleaner and more readable.
This change also adds the `range` property to the type to be used
for source-mapping.
PR Close#38775
Recent work on compiler internals in #38539 led to an unexpected failure,
where a pipe used exclusively inside of an ICU would no longer be
emitted into the compilation output. This caused runtime errors due to
missing pipes.
The issue occurred because the change in #38539 would determine the set
of used pipes up-front, independent from the template compilation using
the `R3TargetBinder`. However, `R3TargetBinder` did not consider
expressions within ICUs, so any pipe usages within those expressions
would not be detected. This fix unblocks #38539 and also concerns
upcoming linker work, given that prelink compilations would not go
through full template compilation but only `R3TargetBinder`.
PR Close#38810
The `MessagePiece` and derived classes, `LiteralPiece` and `PlaceholderPiece`
need to be referenced in the `LocalizedString` output AST class, so that we
can render the source-spans of each piece.
PR Close#38645
The `R3TargetBinder` accepts an interface for directive metadata which
declares types for `input` and `output` objects. These types convey the
mapping between the property names for an input or output and the
corresponding property name on the component class. Due to
`R3TargetBinder`'s requirements, this mapping was specified with property
names as keys and field names as values.
However, because of duck typing, this interface was accidentally satisifed
by the opposite mapping, of field names to property names, that was produced
in other parts of the compiler. This form more naturally represents the data
model for inputs.
Rather than accept the field -> property mapping and invert it, this commit
introduces a new abstraction for such mappings which is bidirectional,
eliminating the ambiguous plain object type. This mapping uses new,
unambiguous terminology ("class property name" and "binding property name")
and can be used to satisfy both the needs of the binder as well as those of
the template type-checker (field -> property).
A new test ensures that the input/output metadata produced by the compiler
during analysis is directly compatible with the binder via this unambiguous
new interface.
PR Close#38685
Previously, the compiler was not able to display template parsing errors as
true `ts.Diagnostic`s that point inside the template. Instead, it would
throw an actual `Error`, and "crash" with a stack trace containing the
template errors.
Not only is this a poor user experience, but it causes the Language Service
to also crash as the user is editing a template (in actuality the LS has to
work around this bug).
With this commit, such parsing errors are converted to true template
diagnostics with appropriate span information to be displayed contextually
along with all other diagnostics. This majorly improves the user experience
and unblocks the Language Service from having to deal with the compiler
"crashing" to report errors.
PR Close#38576
