This patch is the first of a few patches which separates the
styling logic between template bindings (e.g. <div [style])
from host bindings (e.g. @HostBinding('style')). This patch
in particular introduces a series of host-specific styling
instructions and changes the existing set of template styling
instructions not to accept directives. The underyling code (which
communicates with the styling algorithm) still works as it did
before.
This PR also separates the styling instruction code into a separate
file and moves over all other instructions into an dedicated
instructions directory.
PR Close#29292
In the @Component decorator, the 'host' field is an object which represents
host bindings. The type of this field is complex, but is generally of the
form {[key: string]: string}. Several different kinds of bindings can be
specified, depending on the structure of the key.
For example:
```
@Component({
host: {'[prop]': 'someExpr'}
})
```
will bind an expression 'someExpr' to the property 'prop'. This is known to
be a property binding because of the square brackets in the binding key.
If the binding key is a plain string (no brackets or parentheses), then it
is known as an attribute binding. In this case, the right-hand side is not
interpreted as an expression, but is instead a constant string.
There is no actual requirement that at build time, these constant strings
are known to the compiler, but this was previously enforced as a side effect
of requiring the binding expressions for property and event bindings to be
statically known (as they need to be parsed). This commit breaks that
relationship and allows the attribute bindings to be dynamic. In the case
that they are dynamic, the references to the dynamic values are reflected
into the Ivy instructions for attribute bindings.
PR Close#29033
Up until now, `[style]` and `[class]` bindings (the map-based ones) have only
worked as template bindings and have not been supported at all inside of host
bindings. This patch ensures that multiple host binding sources (components and
directives) all properly assign style values and merge them correctly in terms
of priority.
Jira: FW-882
PR Close#28246
With the refactoring or how styles/classes are implmented in Ivy,
interpolation has caused the binding code to mess up since interpolation
itself takes up its own slot in Ivy's memory management code. This patch
makes sure that interpolation works as expected with class and style
bindings.
Jira issue: FW-944
PR Close#28190
Up until this point, all static attribute values (things like `title` and `id`)
defined within the `host` are of a Component/Directive definition were
generated into a `def.attributes` array and then processed at runtime.
This design decision does not lend itself well to tree-shaking and is
inconsistent with other static values such as styles and classes.
This fix ensures that all static attribute values (attributes, classes,
and styles) that exist within a host definition for components and
directives are all assigned via the `elementHostAttrs` instruction.
```
// before
defineDirective({
...
attributes: ['title', 'my title']
...
})
//now
defineDirective({
...
hostBindings: function() {
if (create) {
elementHostAttrs(..., ['title', 'my-title']);
}
...
}
...
})
```
PR Close#28089
