This introduces `AstObject.toMap` as an alternative to `AstObject
.toLiteral`, and adds `AstValue.getSymbolName` to query the symbol name
of a value using the encapsulated AST host.
PR Close#39518
This commit adds the basic building blocks for linking partial declarations.
In particular it provides a generic `FileLinker` class that delegates to
a set of (not yet implemented) `PartialLinker` classes.
The Babel plugin makes use of this `FileLinker` providing concrete classes
for `AstHost` and `AstFactory` that work with Babel AST. It can be created
with the following code:
```ts
const plugin = createEs2015LinkerPlugin({ /* options */ });
```
PR Close#39116
Previously the value passed to `AstFactory.attachComments()` could be
`undefined` which is counterintuitive, since why attach something that
doesn't exist? Now it expects there to be a defined array. Further it no
longer returns a statement. Both these aspects of the interface were designed
to make the usage simpler but has the result of complicating the implemenation.
The `ExpressionTranslatorVisitor` now has a helper function (`attachComments()`)
to handle `leadingComments` being undefined and also returning the statement.
This keeps the usage in the translator simple, while ensuring that the `AstFactory`
API is not influenced by how it is used.
PR Close#39076
This commit adds the `AstHost` interface, along with implementations for
both Babel and TS.
It also implements the Babel vesion of the `AstFactory` interface, along
with a linker specific implementation of the `ImportGenerator` interface.
These classes will be used by the new "ng-linker" to transform prelinked
library code using a Babel plugin.
PR Close#38866
JoostK
Pete Bacon Darwin