[tsserver] api to find references to a file

[mjbvz]

Search Terms

• find references (shift f12)
• TypeScript server

Problem

If you run find all references on an import path, tsserver will return a list of locations where this file is imported:

However it would also be useful to be able to run this command for a file without first having to find where it is imported. Some example use cases:

• Add a command to find references for the currently active file.
• Add a right click option in the explorer to find references to a selected file.

See microsoft/vscode#66150 for details on the VS Code side

Proposal

Add a new FileReferences request to the tsserver protocol. This command would take a file path (and optional project name) and return a list of references:

interface FileReferencesRequest extends FileRequest {
    // empty 
}

interface FileReferencesResponseBody {
	/**
	 * The file locations referencing the symbol.
	 */
	refs: readonly ReferencesResponseItem[];
	/**
	 * The name of the symbol.
	 */
	symbolName: string;
}

interface FileReferencesResponse extends Response {
	body?: FileReferencesResponseBody;
}

Running this command should return a list of locations where the given file is imported (this matches what running find all references on an import path does)

[sheetalkamat]

https://github.com/microsoft/TypeScript/blob/master/src/compiler/program.ts#L758 this should have list where file is referenced from