Find identifiers in scope

[dsherret]

For example:

const var1 = ...;
const var2 = ...;

function func() {
    const var3 = ...;
    callExpr();
    const var4 = ...;

    function innerFunc() {
    }
}

Given the node for callExpr(), it should be possible to call something like getIdentifiersInScope() and it would return these identifiers in the following order: var3, innerFunc, var2, var1 (closest to furthest).

Use case: Figuring out what identifier to use as an argument in a call expression when refactoring an application.

[dsherret]

Looks like getSymbolsInScope in the compiler API would be useful for this.

[dsherret]

In 3.0.0 there is a new method Node#getSymbolsInScope(meaning: ts.SymbolFlags).

const symbols = node.getSymbolsInScope(SymbolFlags.Value);

I'm not sure what a sensible default would be for meaning. Internally in the compiler api, that's a filter on the results. I put in a request to the TS team to see if a default would make sense there. Perhaps SymbolFlags.Value?