Function getDocumentPositionMapper

test/fixtures/snapshot/typescript.js:144552–144567

(generatedFileName, sourceFileName)

            return ts.toPath(fileName, currentDirectory, getCanonicalFileName);
        }
        function getDocumentPositionMapper(generatedFileName, sourceFileName) {
            var path = toPath(generatedFileName);
            var value = documentPositionMappers.get(path);
            if (value)
                return value;
            var mapper;
            if (host.getDocumentPositionMapper) {
                mapper = host.getDocumentPositionMapper(generatedFileName, sourceFileName);
            }
            else if (host.readFile) {
                var file = getSourceFileLike(generatedFileName);
                mapper = file && ts.getDocumentPositionMapper({ getSourceFileLike: getSourceFileLike, getCanonicalFileName: getCanonicalFileName, log: function (s) { return host.log(s); } }, generatedFileName, ts.getLineInfo(file.text, ts.getLineStarts(file)), function (f) { return !host.fileExists || host.fileExists(f) ? host.readFile(f) : undefined; });
            }
            documentPositionMappers.set(path, mapper || ts.identitySourceMapConsumer);
            return mapper || ts.identitySourceMapConsumer;
        }
        function tryGetSourcePosition(info) {
            if (!ts.isDeclarationFileName(info.fileName))
                return undefined;