BREAKING CHANGE:
`OnPushObserve` was an experimental
feature for Dart and had
conceptual performance problems,
as setting up observables is slow.
Use `OnPush` instead.
BREAKING CHANGE:
In Dart we used to support injecting types with generics. As this feature is hard to implement with the upcoming codegen we are dropping it.
Merge cl/115454020 in G3 with this change.
Closes#7262
Now, using `ng.probe(element)` in the browser console returns
a DebugElement when in dev mode.
`ComponentFixture#debugElement` also returns a new DebugElement.
Breaking Change:
This is a breaking change for unit tests. The API for the DebugElement
has changed. Now, there is a DebugElement or DebugNode for every node
in the DOM, not only nodes with an ElementRef. `componentViewChildren` is
removed, and `childNodes` is a list of ElementNodes corresponding to every
child in the DOM. `query` no longer takes a scope parameter, since
the entire rendered DOM is included in the `childNodes`.
Before:
```
componentFixture.debugElement.componentViewChildren[0];
```
After
```
// Depending on the DOM structure of your component, the
// index may have changed or the first component child
// may be a sub-child.
componentFixture.debugElement.children[0];
```
Before:
```
debugElement.query(By.css('div'), Scope.all());
```
After:
```
debugElement.query(By.css('div'));
```
Before:
```
componentFixture.debugElement.elementRef;
```
After:
```
componentFixture.elementRef;
```
BEFORE:
The following would throw in the dev mode because `f` would return a new array when called by checkNoChanges.
@Component({
template: `
{{f()}}
`
})
class A {
f() { return [1]; }
}
AFTER:
The checkNoChanges function compares only primitives types for equality, and deeply compares iterables. Other objects cannot cause checkNoChanges to throw. This means that the dev mode would never fail given a legal program, but may allow some illegal programs.
This is needed to prevent memory leaks. The DOM
listeners don’t need to be removed for simple examples,
but a big internal app shows memory leaks because of them.
BREAKING CHANGE:
- `Renderer.listen` now has to return a function that
removes the event listener.