Commit Graph

485 Commits

Author SHA1 Message Date
Misko Hevery e32b6256ce fix(core): `QueryList` should not fire changes if the underlying list did not change. (#40091)
Previous implementation would fire changes `QueryList.changes.subscribe`
whenever the `QueryList` was recomputed. This resulted in artificially
high number of change notifications, as it is possible that recomputing
`QueryList` results in the same list. When the `QueryList` gets recomputed
is an implementation detail and it should not be the thing which determines
how often change event should fire.

This change introduces a new `emitDistinctChangesOnly` option for
`ContentChildren` and `ViewChildren`.

```
export class QueryCompWithStrictChangeEmitParent {
  @ContentChildren('foo', {
    // This option will become the default in the future
    emitDistinctChangesOnly: true,
  })
  foos!: QueryList<any>;
}
```

PR Close #40091
2021-01-14 13:55:02 -08:00
Andrew Kushnir 6cff877f4f perf(core): make DI decorators tree-shakable when used for `useFactory` deps config (#40145)
This commit updates the logic that calculates `useFactory` function arguments to avoid relying on `instanceof`
checks (thus always retaining symbols) and relies on flags that DI decorators contain (as a monkey-patched property).

Another perf benefit is having less megamorphic reads while calculating args for the `useFactory` call: we used to
check whether a token has `ngMetadataName` property 4 times (in worst case), now we have just 1 megamorphic read in
all cases.

Closes #40143.

PR Close #40145
2021-01-13 14:08:45 -08:00
Martin Sikora 9105005192 refactor(router): refactor and simplify router RxJS chains (#40290)
Refactor and simplifiy RxJS usage in the router package
in order to reduce its size and increase performance.

PR Close #40290
2021-01-11 15:30:55 -08:00
Andrew Scott e43f7e26fe fix(router): apply redirects should match named outlets with empty path parents (#40029)
There are two parts to this commit:
1. Revert the changes from #38379. This change had an incomplete view of
how things worked and also diverged the implementations of
`applyRedirects` and `recognize` even more.
2. Apply the fixes from the `recognize` algorithm to ensure that named
outlets with empty path parents can be matched. This change also passes
all the tests that were added in #38379 with the added benefit of being
a more complete fix that stays in-line with the `recognize` algorithm.
This was made possible by using the same approach for `split` by
always creating segments for empty path matches (previously, this was
only done in `applyRedirects` if there was a `redirectTo` value). At the
end of the expansions, we need to squash all empty segments so that
serializing the final `UrlTree` returns the same result as before.

Fixes #39952
Fixes #10726
Closes #30410

PR Close #40029
2021-01-05 12:43:47 -08:00
Andrew Kushnir a3849611b7 fix(forms): clean up connection between FormControl/FormGroup and corresponding directive instances (#39235)
Prior to this commit, removing `FormControlDirective` and `FormGroupName` directive instances didn't clear
the callbacks previously registered on FromControl/FormGroup class instances. As a result, these callbacks
were executed even after `FormControlDirective` and `FormGroupName` directive instances were destroyed. That was
also causing memory leaks since these callbacks also retained references to DOM elements.

This commit updates the cleanup logic to take care of properly detaching FormControl/FormGroup/FormArray instances
from the view by removing view-specific callback at destroy time.

Closes #20007, #37431, #39590.

PR Close #39235
2021-01-05 11:15:08 -08:00
Andrew Kushnir 3735633bb0 fix(core): take @Host into account while processing `useFactory` arguments (#40122)
DI providers can be defined via `useFactory` function, which may have arguments configured via `deps` array.
The `deps` array may contain DI flags represented by DI decorators (such as `@Self`, `@SkipSelf`, etc). Prior to this
commit, having the `@Host` decorator in `deps` array resulted in runtime error in Ivy. The problem was that the `@Host`
decorator was not taken into account while `useFactory` argument list was constructed, the `@Host` decorator was
treated as a token that should be looked up.

This commit updates the logic which prepares `useFactory` arguments to recognize the `@Host` decorator.

PR Close #40122
2021-01-05 10:14:25 -08:00
Misko Hevery fc1cd07eb0 fix(core): Call `onDestroy` in production mode as well (#40120)
PR #39876 introduced an error where the `onDestroy` of `ComponentRef`
would only get called if `ngDevMode` was set to true. This was because
in dev mode we would freeze `TCleanup` to verify that no more
static cleanup would get added to `TCleanup` array. This ensured
that `TCleanup` was always present in dev mode. In production the
`TCleanup` would get created only when needed. The resulting cleanup
code was incorrectly indented and would only run if `TCleanup` was
present causing this issue.

Fix #40105

PR Close #40120
2020-12-22 08:02:27 -08:00
Misko Hevery 5fc45082ca fix(core): Support extending differs from root `NgModule` (#39981)
Differs tries to inject parent differ in order to support extending.
This does not work in the 'root' injector as the provider overrides the
default injector. The fix is to just assume standard set of providers
and extend those instead.

PR close #25015
Issue close #11309 `Can't extend IterableDiffers`
Issue close #18554 `IterableDiffers.extend is not AOT compatible`
  (This is fixed because we no longer have an arrow function in the
  factory but a proper function which can be imported.)

PR Close #39981
2020-12-07 09:51:27 -08:00
arturovt df27027ecb fix(core): remove application from the testability registry when the root view is removed (#39876)
In the new behavior Angular removes applications from the testability registry when the
root view gets destroyed. This eliminates a memory leak, because before that the
TestabilityRegistry holds references to HTML elements, thus they cannot be GCed.

PR Close #22106

PR Close #39876
2020-12-02 12:56:04 -08:00
cexbrayat 5fa767363d fix(router): remove duplicated getOutlet function (#39764)
The codebase currently contains two `getOutlet` functions,
and they can end up in the bundle of an application.
A recent commit 6fbe21941d tipped us off
as it introduced several `noop` occurrences in the golden symbol files.
After investigating with @petebacondarwin,
we decided to remove the duplicated functions.

This probably shaves only a few bytes,
but this commit removes the duplicated functions,
by always using the one in `router/src/utils/config`.

PR Close #39764
2020-11-20 08:31:14 -08:00
cexbrayat 066126ae2f fix(core): remove duplicated noop function (#39761)
The codebase currently contains several `noop` functions,
and they can end up in the bundle of an application.
A recent commit 6fbe21941d tipped us off
as it introduced several `noop` occurrences in the golden symbol files.
After investigating with @petebacondarwin,
we decided to remove the duplicated functions.

This probably shaves only a few bytes,
but this commit removes the duplicated functions,
by always using the one in `core/src/utils/noop`.

PR Close #39761
2020-11-19 12:14:12 -08:00
Egor 6fbe21941d refactor(core): Replace non-null assertion operator with property initialization (#39730)
Reuse the `noop` function from the common utilities

PR Close #39730
2020-11-18 09:14:41 -08:00
Misko Hevery e6ae0c5349 refactor(core): Remove circular dependency between `LContainer` and `ViewRef`. (#39621)
`LContainer` stores `ViewRef`s this is not quite right as it creates
circular dependency between the two types. Also `LContainer` should not
be aware of `ViewRef` which iv ViewEngine specific construct.

PR Close #39621
2020-11-16 09:12:46 -08:00
Misko Hevery 8574c3000e refactor(core): Cleanup non-standard `Injector` handling. (#39621)
Due to historical reasons `Injector.__NG_ELEMENT_ID__` was set to `-1`.
This changes it to be consistent with other `*Ref.__NG_ELEMENT_ID__`
constructs.

PR Close #39621
2020-11-16 09:12:46 -08:00
Misko Hevery 739d745eb5 refactor(core): Cleanup circular dependency between ViewEngine and Ivy `ViewContainerRef`. (#39621)
`ViewContainerRef` is declared in ViewEngine but it sub-classed in Ivy. This creates a circular
dependency between ViewEngine `ViewContainerRef` which needs to declare `__NG_ELEMENT_ID__` and
ivy factory which needs to create it. The workaround used to be to pass the `ViewContainerRef`
through stack but that created a very convoluted code. This refactoring simply bundles the
two files together and removes the stack workaround making the code simpler to follow.

PR Close #39621
2020-11-16 09:12:46 -08:00
Misko Hevery 453f196c4d refactor(core): Cleanup circular dependency between ViewEngine and Ivy `TemplateRef`. (#39621)
`TemplateRef` is declared in ViewEngine but it sub-classed in Ivy. This creates a circular
dependency between ViewEngine `TemplateRef` which needs to declare `__NG_ELEMENT_ID__` and
ivy factory which needs to create it. The workaround used to be to pass the `TemplateRef`
through stack but that created a very convoluted code. This refactoring simply bundles the
two files together and removes the stack workaround making the code simpler to follow.

PR Close #39621
2020-11-16 09:12:45 -08:00
Kristiyan Kostadinov b015d3e950 fix(core): not inserting ViewContainerRef nodes when inside root of a component (#39599)
When a `ViewContainerRef` is injected, we dynamically create a comment node next to the host
so that it can be used as an anchor point for inserting views. The comment node is inserted
through the `appendChild` helper from `node_manipulation.ts` in most cases.

The problem with using `appendChild` here is that it has some extra logic which doesn't return
a parent `RNode` if an element is at the root of a component. I __think__ that this is a performance
optimization which is used to avoid inserting an element in one place in the DOM and then
moving it a bit later when it is projected. This can break down in some cases when creating
a `ViewContainerRef` for a non-component node at the root of another component like the following:

```
<root>
  <div #viewContainerRef></div>
</root>
```

In this case the `#viewContainerRef` node is at the root of a component so we intentionally don't
insert it, but since its anchor element was created manually, it'll never be projected. This will
prevent any views added through the `ViewContainerRef` from being inserted into the DOM.

These changes resolve the issue by not going through `appendChild` at all when creating a comment
node for `ViewContainerRef`. This should work identically since `appendChild` doesn't really do
anything with the T structures anyway, it only uses them to reach the relevant DOM nodes.

Fixes #39556.

PR Close #39599
2020-11-12 11:37:00 -08:00
Andrew Kushnir 1bc53eb303 fix(forms): more precise control cleanup (#39623)
Currently when an instance of the `FormControlName` directive is destroyed, the Forms package invokes
the `cleanUpControl` to clear all directive-specific logic (such as validators, onChange handlers,
etc) from a bound control. The logic of the `cleanUpControl` function should revert all setup
performed by the `setUpControl` function. However the `cleanUpControl` is too aggressive and removes
all callbacks related to the onChange and disabled state handling. This is causing problems when
a form control is bound to multiple FormControlName` directives, causing other instances of that
directive to stop working correctly when the first one is destroyed.

This commit updates the cleanup logic to only remove callbacks added while setting up a control
for a given directive instance.

The fix is needed to allow adding `cleanUpControl` function to other places where cleanup is needed
(missing this function calls in some other places causes memory leak issues).

PR Close #39623
2020-11-12 09:38:19 -08:00
Jessica Janiuk 290ea57a93 fix(core): Access injected parent values using SelfSkip (#39464)
In ViewEngine, SelfSkip would navigate up the tree to get tokens from
the parent node, skipping the child. This restores that functionality in
Ivy. In ViewEngine, if a special token (e.g. ElementRef) was not found
in the NodeInjector tree, the ModuleInjector was also used to lookup
that token. While special tokens like ElementRef make sense only in a
context of a NodeInjector, we preserved ViewEngine logic for now to
avoid breaking changes.

We identified 4 scenarios related to @SkipSelf and special tokens where
ViewEngine behavior was incorrect and is likely due to bugs. In Ivy this
is implemented to provide a more intuitive API. The list of scenarios
can be found below.

1. When Injector is used in combination with @Host and @SkipSelf on the
first Component within a module and the injector is defined in the
module, ViewEngine will get the injector from the module. In Ivy, it
does not do this and throws instead.

2. When retrieving a @ViewContainerRef while @SkipSelf and @Host are
present, in ViewEngine, it throws an exception. In Ivy it returns the
host ViewContainerRef.

3. When retrieving a @ViewContainerRef on an embedded view and @SkipSelf
is present, in ViewEngine, the ref is null. In Ivy it returns the parent
ViewContainerRef.

4. When utilizing viewProviders and providers, a child component that is
nested within a parent component that has @SkipSelf on a viewProvider
value, if that provider is provided by the parent component's
viewProviders and providers, ViewEngine will return that parent's
viewProviders value, which violates how viewProviders' visibility should
work. In Ivy, it retrieves the value from providers, as it should.

These discrepancies all behave as they should in Ivy and are likely bugs
in ViewEngine.

PR Close #39464
2020-11-06 09:23:45 -08:00
Andrew Kushnir e96b379385 fix(forms): remove validators while cleaning up a control (#39234)
Prior to this commit, the `cleanUpControl` function (responsible for cleaning up control instance)
was not taking validators into account. As a result, these validators remain registered on a detached
form control instance, thus causing memory leaks. This commit updates the `cleanUpControl` function
logic to also run validators cleanup.

As a part of this change, the logic to setup and cleanup validators was refactored and moved to
separate functions (with completely opposite behavior), so that they can be reused in the future.

This commit doesn't add the `cleanUpControl` calls to all possible places, it just fixes the cases
where this function is being called, but doesn't fully perform a cleanup. The `cleanUpControl`
function calls will be added to other parts of code (to avoid more memory leaks) in a followup PR.

PR Close #39234
2020-11-04 10:58:24 -08:00
Andrew Scott ff7a62ee21 refactor(router): Small refactor of createUrlTree and extra tests (#39456)
This commit has a small refactor of some methods in create_url_tree.ts
and adds some test cases, including two that will fail at the moment but
should pass. A follow-up commit will make use of the refactorings to fix
the test with minimal changes.

PR Close #39456
2020-10-30 16:23:03 -07:00
twerske e6ca3d3841 refactor(core): add top 10 runtime error codes (#39188)
adds RuntimeError and code enum to improve debugging experience
refactor ExpressionChangedAfterItHasBeenCheckedError to code NG0100
refactor CyclicDependency to code NG0200
refactor No Provider to code NG0201
refactor MultipleComponentsMatch to code NG0300
refactor ExportNotFound to code NG0301
refactor PipeNotFound to code NG0302
refactor BindingNotKnown to code NG0303
refactor NotKnownElement to code NG0304

PR Close #39188
2020-10-28 10:05:01 -07:00
twerske dcafac1b8f refactor(core): group provider and circular errors (#39251)
group together similar error messages as part of error code efforts
ProviderNotFound & NodeInjector grouped into throwProviderNotFoundError
Cyclic dependency errors grouped into throwCyclicDependencyError

PR Close #39251
2020-10-22 13:42:34 -07:00
Misko Hevery d939b5f598 refactor(core): Improve tree shakability of i18n code. (#39301)
`TNode.insertBeforeIndex` is only populated when i18n is present. This
change puts all code which reads `insertBeforeIndex` behind a
dynamically loaded functions which are set only when i18n code executes.

PR Close #39301
2020-10-22 09:35:49 -07:00
Misko Hevery 68d4de6770 refactor(core): Replace `ExpandoInstructions` with `HostBindingOpCodes` (#39301)
The `ExpandoInstructions` was unnecessarily convoluted way to solve the
problem of calling the `HostBindingFunction`s on components and
directives. The code was complicated and hard to fallow.

The replacement is a simplified way to achieve the same thing, which
is also more efficient in space and speed.

PR Close #39301
2020-10-22 09:35:48 -07:00
Misko Hevery ca11ef2376 fix(core): Store ICU state in `LView` rather than in `TView` (#39233)
Before this refactoring/fix the ICU would store the current selected
index in `TView`. This is incorrect, since if ICU is in `ngFor` it will
cause issues in some circumstances. This refactoring properly moves the
state to `LView`.

closes #37021
closes #38144
closes #38073

PR Close #39233
2020-10-21 18:33:00 -07:00
Jessica Janiuk a3812c6cbd refactor(core): renames checkNoChangesMode to be clearer (#39277)
getCheckNoChangesMode was discovered to be unclear as to the purpose of
it. This refactor is a simple renaming to make it much clearer what that
method and property does.

PR Close #39277
2020-10-15 17:01:20 -07:00
Andrew Kushnir db37c17e02 refactor(core): remove NG_PROV_DEF_FALLBACK needed for IE10 only (#39090)
This commit removes a workaround previously used for IE 9 and 10 to identify whether InjectableDef
was defined on a given class instance. Since support for IE 9 and 10 is removed, this fallback is
no longer needed.

PR Close #39090
2020-10-13 15:51:48 -07:00
Misko Hevery fc3b3fe39e docs(core): Update instructions on updating symbol tests (#38707)
PR Close #38707
2020-09-28 16:15:59 -04:00
Misko Hevery 5448e84cf0 refactor(core): renamed `previousOrParent` to `currentTNode` (#38707)
The previous name of `previousOrParent` was confusing. Changed the
terminology to `currentTNode`.

PR Close #38707
2020-09-28 16:15:59 -04:00
Misko Hevery 5db84d7221 refactor(core): Remove `TViewNode` as it is no longer used. (#38707)
Previous commit change the logic to not rely on the `TViewNode` this
change removes it entirely.

PR Close #38707
2020-09-28 16:15:59 -04:00
Misko Hevery eb32b6bd6b refactor(core): Remove reliance on `TNodeType.View`. (#38707)
`TNodeType.View` was created to support inline views. That feature did
not materialize and we have since removed the instructions for it, leave
 an unneeded `TNodeType.View` which was still used in a very
 inconsistent way. This change no longer created `TNodeType.View` (and
 there will be a follow up chang to completely remove it.)

Also simplified the mental model so that `LView[HOST]`/`LView[T_HOST]`
always point to the insertion location of the `LView`.

PR Close #38707
2020-09-28 16:15:59 -04:00
Misko Hevery 9fb541787c refactor(core): Remove host `TNode` from `getOrCreateTNode` (#38707)
Host `TNode` was passed into `getOrCreateTNode` just so that we can
compute weather or not we are a root node. This was needed because
`previousOrParentTNode` could have `TNode` from `TView` other then
current `TView`. This is confusing mental model. Previous change
ensured that `previousOrParentTNode` must always be part of `TView`,
which enabled this change to remove the unneeded argument.

PR Close #38707
2020-09-28 16:15:59 -04:00
Misko Hevery 812615bb99 refactor(core): Ensure that `previousOrParentTNode` always belongs to current `TView`. (#38707)
`previousOrParentTNode` stores current `TNode`. Due to inconsistent
implementation the value stored would sometimes belong to the current
`TView` and sometimes to the parent. We have extra logic which accounts
for it. A better solution is to just ensure that `previousOrParentTNode`
always belongs to current `TNode`. This simplifies the mental model
and cleans up some code.

PR Close #38707
2020-09-28 16:15:58 -04:00
Joey Perrott 593bd594e3 build: create temporary script for symbol extractor tests (#38819)
Creates a temporary script to running all symbol extractor tests.

PR Close #38819
2020-09-14 16:54:39 -07:00
Sonu Kapoor 57c442f930 build(router): update symbols for routing app (#38817)
This commit updates the golden symbol files for the routing app.

PR Close #38817
2020-09-11 13:20:34 -07:00
Sonu Kapoor f667e374a9 build: create sample router app (#38714)
This commit creates a sample router test application to introduce the
symbol tests. It serves as a guard to ensure that any future work on the
router package does not unintentionally increase the payload size.

PR Close #38714
2020-09-11 12:10:46 -07:00
Sonu Kapoor 1150649139 perf(core): use `ngDevMode` to tree-shake error messages (#38612)
This commit adds `ngDevMode` guard to throw some errors only in dev mode
(similar to how things work in other parts of Ivy runtime code). The
`ngDevMode` flag helps to tree-shake these error messages from production
builds (in dev mode everything will work as it works right now) to decrease
production bundle size.

PR Close #38612
2020-09-08 11:41:43 -07:00
Sonu Kapoor 201a546af8 perf(forms): use internal `ngDevMode` flag to tree-shake error messages in prod builds (#37821)
This commit adds a guard before throwing any forms errors. This will tree-shake
error messages which cannot be minified. It should also help to reduce the
bundle size of the `forms` package in production by ~20%.

Closes #37697

PR Close #37821
2020-08-24 09:26:28 -07:00
Andrew Kushnir 856db56cca refactor(forms): get rid of duplicate functions (#38371)
This commit performs minor refactoring in Forms package to get rid of duplicate functions.
It looks like the functions were duplicated due to a slightly different type signatures, but
their logic is completely identical. The logic in retained functions remains the same and now
these function also accept a generic type to achieve the same level of type safety.

PR Close #38371
2020-08-07 11:40:04 -07:00
Sonu Kapoor 7b2e2f5d91 build(forms): create sample forms app (#38044)
This commit creates a sample forms test application to introduce the symbol
tests. It serves as a guard to ensure that any future work on the
forms package does not unintentionally increase the payload size.

PR Close #38044
2020-07-23 11:04:46 -07:00
Paul Gschwendtner e382632473 build: fix symbol extractor not dealing with ES2015 classes (#38093)
We recently reworked our `ng_rollup_bundle` rule to no longer output
ESM5 and to optimize applications properly (previously applications were
not optimized properly due to incorrect build optimizer setup).

This change meant that a lot of symbols have been removed from the
golden correctly. See: fd65958b88

Unfortunately though, a few symbols have been accidentally removed
because they are now part of the bundle as ES2015 classes which the
symbol extractor does not pick up. This commit fixes the symbol
extractor to capture ES2015 classes. We also update the golden to
reflect this change.

PR Close #38093
2020-07-16 13:54:23 -07:00
Misko Hevery 737506e79c fix(core): Allow modification of lifecycle hooks any time before bootstrap (#35464)
Currently we read lifecycle hooks eagerly during `ɵɵdefineComponent`.
The result is that it is not possible to do any sort of meta-programing
such as mixins or adding lifecycle hooks using custom decorators since
any such code executes after `ɵɵdefineComponent` has extracted the
lifecycle hooks from the prototype. Additionally the behavior is
inconsistent between AOT and JIT mode. In JIT mode overriding lifecycle
hooks is possible because the whole `ɵɵdefineComponent` is placed in
getter which is executed lazily. This is because JIT mode must compile a
template which can be specified as `templateURL` and those we are
waiting for its resolution.

- `+` `ɵɵdefineComponent` becomes smaller as it no longer needs to copy
  lifecycle hooks from prototype to `ComponentDef`
- `-` `ɵɵNgOnChangesFeature` feature is now always included with the
  codebase as it is no longer tree shakable.

Previously we have read lifecycle hooks from prototype in the
`ɵɵdefineComponent` so that lifecycle hook access would be monomorphic.
This decision was made before we had `T*` data structures. By not
reading the lifecycle hooks we are moving the megamorhic read form
`ɵɵdefineComponent` to instructions. However, the reads happen on
`firstTemplatePass` only and are subsequently cached in the `T*` data
structures. The result is that the overall performance should be same
(or slightly better as the intermediate `ComponentDef` has been
removed.)

- [ ] Remove `ɵɵNgOnChangesFeature` from compiler. (It will no longer
      be a feature.)
- [ ] Discuss the future of `Features` as they hinder meta-programing.

Fix #30497

PR Close #35464
2020-07-15 16:22:46 -07:00
Paul Gschwendtner fd65958b88 test: update symbol goldens to reflect optimized application (#37623)
Interestingly enough, our rollup bundle optimization pipeline
did not work properly before 1b827b058e5060963590628d4735e6ac83c6dfdd.

Unused declarations were not elided because build optimizer did not
consider the Angular packages as side-effect free. Build optimizer has
a hard-coded list of Angular packages that are considered side-effect
free. Though this one did not match in the old version of the rollup
bundle rule, as internal sources were resolved through their resolved
bazel-out paths. Hence build optimizer could not detect the known
Angular framework packages. Now though, since we leverage the
Bazel-idiomatic `@bazel/rollup` implementation, sources are resolved
through linked `node_modules`, and build optimizer is able to properly
detect files as side-effect free.

PR Close #37623
2020-06-22 10:55:29 -07:00
Paul Gschwendtner 401ef71ae5 fix(compiler-cli): downlevel angular decorators to static properties (#37382)
In v7 of Angular we removed `tsickle` from the default `ngc` pipeline.
This had the negative potential of breaking ES2015 output and SSR due
to a limitation in TypeScript.

TypeScript by default preserves type information for decorated constructor
parameters when `emitDecoratorMetadata` is enabled. For example,
consider this snippet below:

```
@Directive()
export class MyDirective {
  constructor(button: MyButton) {}
}

export class MyButton {}
```

TypeScript would generate metadata for the `MyDirective` class it has
a decorator applied. This metadata would be needed in JIT mode, or
for libraries that provide `MyDirective` through NPM. The metadata would
look as followed:

```
let MyDirective = class MyDir {}

MyDirective = __decorate([
  Directive(),
  __metadata("design:paramtypes", [MyButton]),
], MyDirective);

let MyButton = class MyButton {}
```

Notice that TypeScript generated calls to `__decorate` and
`__metadata`. These calls are needed so that the Angular compiler
is able to determine whether `MyDirective` is actually an directive,
and what types are needed for dependency injection.

The limitation surfaces in this concrete example because `MyButton`
is declared after the `__metadata(..)` call, while `__metadata`
actually directly references `MyButton`. This is illegal though because
`MyButton` has not been declared at this point. This is due to the
so-called temporal dead zone in JavaScript. Errors like followed will
be reported at runtime when such file/code evaluates:

```
Uncaught ReferenceError: Cannot access 'MyButton' before initialization
```

As noted, this is a TypeScript limitation because ideally TypeScript
shouldn't evaluate `__metadata`/reference `MyButton` immediately.
Instead, it should defer the reference until `MyButton` is actually
declared. This limitation will not be fixed by the TypeScript team
though because it's a limitation as per current design and they will
only revisit this once the tc39 decorator proposal is finalized
(currently stage-2 at time of writing).

Given this wontfix on the TypeScript side, and our heavy reliance on
this metadata in libraries (and for JIT mode), we intend to fix this
from within the Angular compiler by downleveling decorators to static
properties that don't need to evaluate directly. For example:

```
MyDirective.ctorParameters = () => [MyButton];
```

With this snippet above, `MyButton` is not referenced directly. Only
lazily when the Angular runtime needs it. This mitigates the temporal
dead zone issue caused by a limitation in TypeScript's decorator
metadata output. See: https://github.com/microsoft/TypeScript/issues/27519.

In the past (as noted; before version 7), the Angular compiler by
default used tsickle that already performed this transformation. We
moved the transformation to the CLI for JIT and `ng-packager`, but now
we realize that we can move this all to a single place in the compiler
so that standalone ngc consumers can benefit too, and that we can
disable tsickle in our Bazel `ngc-wrapped` pipeline (that currently
still relies on tsickle to perform this decorator processing).

This transformation also has another positive side-effect of making
Angular application/library code more compatible with server-side
rendering. In principle, TypeScript would also preserve type information
for decorated class members (similar to how it did that for constructor
parameters) at runtime. This becomes an issue when your application
relies on native DOM globals for decorated class member types. e.g.

```
@Input() panelElement: HTMLElement;
```

Your application code would then reference `HTMLElement` directly
whenever the source file is loaded in NodeJS for SSR. `HTMLElement`
does not exist on the server though, so that will become an invalid
reference. One could work around this by providing global mocks for
these DOM symbols, but that doesn't match up with other places where
dependency injection is used for mocking DOM/browser specific symbols.

More context in this issue: #30586. The TL;DR here is that the Angular
compiler does not care about types for these class members, so it won't
ever reference `HTMLElement` at runtime.

Fixes #30106. Fixes #30586. Fixes #30141.
Resolves FW-2196. Resolves FW-2199.

PR Close #37382
2020-06-10 09:24:11 -07:00
Andrew Scott 4456e7e4de refactor(core): remove `looseIdentical` in favor of built-in `Object.is` (#37191)
Remove `looseIdentical` implementation and instead use the ES2015 `Object.is` in its place.
They behave exactly the same way except for `+0`/`-0`.
`looseIdentical(+0, -0)` => `true`
`Object.is(+0, -0)` => `false`

Other than the difference noted above, this is not be a breaking change because:
1. `looseIdentical` is a private API
2. ES2015 is listed as a mandatory polyfill in the [browser support
guide](https://angular.io/guide/browser-support#mandatory-polyfills)
3. Also note that `Ivy` already uses `Object.is` in `bindingUpdated`.

PR Close #37191
2020-06-01 17:19:17 -04:00
Joey Perrott d1ea1f4c7f build: update license headers to reference Google LLC (#37205)
Update the license headers throughout the repository to reference Google LLC
rather than Google Inc, for the required license headers.

PR Close #37205
2020-05-26 14:26:58 -04:00
Andrew Scott aaa89bb715 refactor(core): rename refreshDynamicEmbeddedViews to refreshEmbeddedViews (#37117)
Dynamic embedded views were conceptually different from inline embedded views, but we have since
removed the inline embedded views so we now only have "embedded views".
See related refactoring work to remove inline embedded views in #34715
and #37073.

PR Close #37117
2020-05-14 15:50:52 -07:00
Andrew Scott 047642556c refactor(core): remove ActiveIndexFlag from LContainer (#37073)
The ActiveIndexFlag is no longer needed because we no longer have "inline embedded views".
There is only one type of embedded view so we do not need complex tracking for
inline embedded views.

HAS_TRANSPLANTED_VIEWS now takes the place of the ACTIVE_INDEX slot as a
simple boolean rather than being a shifted flag inside the ACTIVE_INDEX bits.

PR Close #37073
2020-05-13 16:00:41 -07:00
Matias Niemelä 45f4a47286 refactor(core): remove style sanitization code for `[style]`/`[style.prop]` bindings (#36965)
In 420b9be1c1 all style-based sanitization code was
disabled because modern browsers no longer allow for javascript expressions within
CSS. This patch is a follow-up patch which removes all traces of style sanitization
code (both instructions and runtime logic) for the `[style]` and `[style.prop]` bindings.

PR Close #36965
2020-05-13 15:56:12 -07:00