ngtsc has a robust suite of testing utilities, designed for in-memory
testing of a TypeScript compiler. Previously these utilities lived in the
`test` directory for the compiler-cli package.
This commit moves those utilities to an `ngtsc/testing` package, enabling
them to be depended on separately and opening the door for using them from
the upcoming language server testing infrastructure.
As part of this refactoring, the `fake_core` package (a lightweight API
replacement for @angular/core) is expanded to include functionality needed
for Language Service test use cases.
PR Close#39594
It is quite common for the TS compiler to have to add synthetic
types to function signatures, where the developer has not
explicitly provided them. This results in `import(...)` expressions
appearing in typings files. For example in `@ngrx/data` there is a
class with a getter that has an implicit type:
```ts
export declare class EntityCollectionServiceBase<...> {
...
get store() {
return this.dispatcher.store;
}
...
}
```
In the d.ts file for this we get:
```ts
get store(): Store<import("@ngrx/data").EntityCache>;
```
Given that this file is within the `@ngrx/data` package already,
this caused ngcc to believe that there was a circular dependency,
causing it to fail to process the package - and in fact crash!
This commit resolves this problem by ignoring `import()` expressions
when scanning typings programs for dependencies. This ability was
only introduced very recently in a 10.0.0 RC release, and so it has
limited benefit given that up till now ngcc has been able to process
libraries effectively without it. Moreover, in the rare case that a
package does have such a dependency, it should get picked up
by the sync ngcc+CLI integration point.
PR Close#37503
When searching the typings program for a package for imports a
distinction is drawn between missing entry-points and deep imports.
Previously in the `DtsDependencyHost` these deep imports may be
marked as missing if there was no typings file at the deep import path.
Instead there may be a javascript file instead. In practice this means
the import is "deep" and not "missing".
Now the `DtsDependencyHost` will also consider `.js` files when checking
for deep-imports, and it will also look inside `@types/...` for a suitable
deep-imported typings file.
Fixes#34720
PR Close#34695
