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/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
import { getInternalSymbols } from "./getSymbols";
function findBestMatchExpression(sourceId, tokenPos) {
const symbols = getInternalSymbols(sourceId);
if (!symbols) {
return null;
}
const { line, column } = tokenPos;
const { memberExpressions, identifiers, literals } = symbols;
function matchExpression(expression) {
const { location } = expression;
const { start, end } = location;
return start.line == line && start.column <= column && end.column >= column;
}
function matchMemberExpression(expression) {
// For member expressions we ignore "computed" member expressions `foo[bar]`,
// to only match the one that looks like: `foo.bar`.
return !expression.computed && matchExpression(expression);
}
// Avoid duplicating these arrays and be careful about performance as they can be large
//
// Process member expressions first as they can be including identifiers which
// are subset of the member expression.
// Ex: `foo.bar` is a member expression made of `foo` and `bar` identifiers.
return (
memberExpressions.find(matchMemberExpression) ||
literals.find(matchExpression) ||
identifiers.find(matchExpression)
);
}
export default findBestMatchExpression;