b861e9c0ac
As a performance optimization, this commit splits the single __ngtypecheck__.ts file which was previously added to the user's program as a container for all template type-checking code into multiple .ngtypecheck shim files, one for each original file in the user's program. In larger applications, the generation, parsing, and checking of this single type-checking file was a huge performance bottleneck, with the file often exceeding 1 MB in text content. Particularly in incremental builds, regenerating this single file for the entire application proved especially expensive. This commit introduces a new strategy for template type-checking code which makes use of a new interface, the `TypeCheckingProgramStrategy`. This interface abstracts the process of creating a new `ts.Program` to type-check a particular compilation, and allows the mechanism there to be kept separate from the more complex logic around dealing with multiple .ngtypecheck files. A new `TemplateTypeChecker` hosts that logic and interacts with the `TypeCheckingProgramStrategy` to actually generate and return diagnostics. The `TypeCheckContext` class, previously the workhorse of template type- checking, is now solely focused on collecting and generating type-checking file contents. A side effect of implementing the new `TypeCheckingProgramStrategy` in this way is that the API is designed to be suitable for use by the Angular Language Service as well. The LS also needs to type-check components, but has its own method for constructing a `ts.Program` with type-checking code. Note that this commit does not make the actual checking of templates at all _incremental_ just yet. That will happen in a future commit. PR Close #36211
Angular
The sources for this package are in the main Angular repo. Please file issues and pull requests against that repo.
Usage information and reference details can be found in Angular documentation.
License: MIT