Document and/or deprecate Node's getFullStart() vs. pos?

[JoshuaKGoldberg]

Acknowledgement

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Comment

Coming over from typescript-eslint/typescript-eslint#8227 -> https://discord.com/channels/508357248330760243/640177429775777792/1194002057858916483: it looks like ts.Node objects have both a pos: number property and a getFullStart(): number method that directly returns this.pos:

TypeScript/src/services/services.ts

Lines 564 to 566 in 02f9ddf

	public getFullStart(): number {
	return this.pos;
	}

Doing some quick Find all references from the interfaces' definitions in VS Code:

• Node's getFullStart() has 25 results
• ReadonlyTextRanges readonly pos has 407 results

I looked through the GitHub repo and code history but couldn't find anything justifying why both exist. My hunch is maybe that #9529 which added getFullStart() predates TS 2.0's readonly (TS 2.0 release notes > readonly)?

Given that getFullStart() incurs an extra function call, is there any reason beyond backwards compatibility to keep it around? If not, would the team be open to marking it as @deprecated in JSDoc to reduce ambiguity?

[RyanCavanaugh]

No one can remember anything about this. Let's try a PR to deprecate it and replace the remaining usages with pos