Function getTokenAtPositionWorker

test/fixtures/snapshot/typescript.js:127419–127501

Get the token whose text contains the position

(sourceFile, position, allowPositionInLeadingTrivia, includePrecedingTokenAtEndPosition, includeEndPosition)

    ts.getTokenAtPosition = getTokenAtPosition;
    /** Get the token whose text contains the position */
    function getTokenAtPositionWorker(sourceFile, position, allowPositionInLeadingTrivia, includePrecedingTokenAtEndPosition, includeEndPosition) {
        var current = sourceFile;
        var foundToken;
        var _loop_1 = function () {
            // find the child that contains 'position'
            var children = current.getChildren(sourceFile);
            var i = ts.binarySearchKey(children, position, function (_, i) { return i; }, function (middle, _) {
                // This last callback is more of a selector than a comparator -
                // `EqualTo` causes the `middle` result to be returned
                // `GreaterThan` causes recursion on the left of the middle
                // `LessThan` causes recursion on the right of the middle
                // Let's say you have 3 nodes, spanning positons
                // pos: 1, end: 3
                // pos: 3, end: 3
                // pos: 3, end: 5
                // and you're looking for the token at positon 3 - all 3 of these nodes are overlapping with position 3.
                // In fact, there's a _good argument_ that node 2 shouldn't even be allowed to exist - depending on if
                // the start or end of the ranges are considered inclusive, it's either wholly subsumed by the first or the last node.
                // Unfortunately, such nodes do exist. :( - See fourslash/completionsImport_tsx.tsx - empty jsx attributes create
                // a zero-length node.
                // What also you may not expect is that which node we return depends on the includePrecedingTokenAtEndPosition flag.
                // Specifically, if includePrecedingTokenAtEndPosition is set, we return the 1-3 node, while if it's unset, we
                // return the 3-5 node. (The zero length node is never correct.) This is because the includePrecedingTokenAtEndPosition
                // flag causes us to return the first node whose end position matches the position and which produces and acceptable token
                // kind. Meanwhile, if includePrecedingTokenAtEndPosition is unset, we look for the first node whose start is <= the
                // position and whose end is greater than the position.
                var start = allowPositionInLeadingTrivia ? children[middle].getFullStart() : children[middle].getStart(sourceFile, /*includeJsDoc*/ true);
                if (start > position) {
                    return 1 /* Comparison.GreaterThan */;
                }
                // first element whose start position is before the input and whose end position is after or equal to the input
                if (nodeContainsPosition(children[middle])) {
                    if (children[middle - 1]) {
                        // we want the _first_ element that contains the position, so left-recur if the prior node also contains the position
                        if (nodeContainsPosition(children[middle - 1])) {
                            return 1 /* Comparison.GreaterThan */;
                        }
                    }
                    return 0 /* Comparison.EqualTo */;
                }
                // this complex condition makes us left-recur around a zero-length node when includePrecedingTokenAtEndPosition is set, rather than right-recur on it
                if (includePrecedingTokenAtEndPosition && start === position && children[middle - 1] && children[middle - 1].getEnd() === position && nodeContainsPosition(children[middle - 1])) {
                    return 1 /* Comparison.GreaterThan */;
                }
                return -1 /* Comparison.LessThan */;
            });
            if (foundToken) {
                return { value: foundToken };
            }
            if (i >= 0 && children[i]) {
                current = children[i];
                return "continue-outer";
            }
            return { value: current };
        };
        outer: while (true) {
            var state_1 = _loop_1();
            if (typeof state_1 === "object")