We now use module auto-detection and no TypeScript mode. This only affects extern extraction in `AutoBuild`, everything else sets these options explicitly. We currently do not have any ES2015 modules or TypeScript code in our externs, so in practice this is behaviour-preserving.
JavaScript extractor
This directory contains the source code of the JavaScript extractor. The extractor depends on various libraries that are not currently bundled with the source code, so at present it cannot be built in isolation.
The extractor consists of a parser for the latest version of ECMAScript, including a few proposed and historic extensions (see src/com/semmle/jcorn), classes for representing JavaScript and TypeScript ASTs (src/com/semmle/js/ast and src/com/semmle/ts/ast), and various other bits of functionality. Historically, the main entry point of the JavaScript extractor has been com.semmle.js.extractor.Main. However, this class is slowly being phased out in favour of com.semmle.js.extractor.AutoBuild, which is the entry point used by LGTM.
License
Like the LGTM queries, the JavaScript extractor is licensed under Apache License 2.0 by Semmle.