Project references in a program

[sheetalkamat]

Adds support to parse project reference configs, redirect to either output or source depending on options

TODOs as next PR:

• Finding right default project
• Combining results from multiple projects for FAR
• Verifying project references and its options

[Copilot]

Pull Request Overview

Adds support for parsing and applying project reference configurations, enabling conditional redirection between source files and generated declaration outputs.

• Replace a simple map with a thread-safe SyncMap for extended config caching and update performCompilation accordingly.
• Introduce core helpers to resolve project reference paths and compute common source directories.
• Extend the file loader, program, and checker to generate parse tasks for project references and redirect module resolution based on options.

Reviewed Changes

Copilot reviewed 56 out of 56 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
internal/execute/tsc.go	Swap out map-based cache for SyncMap and update performCompilation API
internal/core/projectreference.go	Add functions to resolve project reference config file paths
internal/core/commonsourcedirectory.go	Implement logic to compute common source directory for a set of files
internal/compiler/fileloader.go	Hook in project reference parse tasks and initialize the reference mapper
internal/checker/utilities.go	Extend SkipTypeChecking to skip files originating from project references

Comments suppressed due to low confidence (4)

internal/core/commonsourcedirectory.go:1

• [nitpick] New functions like computeCommonSourceDirectoryOfFilenames lack unit tests; consider adding tests for various path layouts and edge cases.

package core

internal/core/projectreference.go:11

• [nitpick] Add unit tests for ResolveProjectReferencePath (and its helper) to verify correct handling of JSON vs directory inputs.

func ResolveProjectReferencePath(ref *ProjectReference) string {

internal/core/commonsourcedirectory.go:20

• The helper 'min' is undefined; compute the minimum explicitly (e.g., if a < b { n = a } else { n = b }) or import a valid utility.

n := min(len(commonPathComponents), len(sourcePathComponents))

internal/core/commonsourcedirectory.go:21

• Cannot range over an integer; replace with a classic for loop: for i := 0; i < n; i++ { ... }.

for i := range n {

[jakebailey]

Do we actually do this concurrently enough to require a SyncMap?

[sheetalkamat]

we will with project references - many projects could be using same extends cache and parsing at the same time.

[jakebailey]

I am suspicious of collections.Set[K] just because it's an auto-initializing struct containing a map, which means passing it by value will cause separate call chains to not actually share that underlying map. Perhaps a pointer is warranted here?

[jakebailey]

I guess this probably works out because the first thing it does is add the task, so any recursive calls will have preinitialized the map.

[sheetalkamat]

Yeah. which is why i didnt make it address but i can if thats more clear

[jakebailey]

I guess it's fine for now. I'll probably noCopy these in the future to make the bug impossible, but there's technically no bug here.