This was previously flagged if `exports` wasn't used any further. While it's true that the assignment to `exports` is redundant in this case, the assignment is also flagged by DeadStorOfLocal, so there is no point in InvalidExport flagging it as well.
Instead of having many small independent tests, we now just have a single test that pulls in all the individual tests and runs them together.
Concretely, each `.ql` file has been turned into a `.qll` file with a query predicate corresponding to the original `select` clause and named after the original `.ql` file, plus a prefix `test_`.
The newly added `tests.ql` imports all these `.qll`s.
The individual `.expected` files have been concatenated together into `tests.expected`, each prefixed with the name of the corresponding query predicate. (This is the format that qltest produces for tests with multiple query predicates.)
Every once in a while we encounter projects using some custom file extension for files that we could in principle extract, but since the extractor doesn't know about the extension the files are skipped.
To handle this, the legacy extractor has a `--file-type` option that one can use to specify a file type to use for all files in that particular extraction. So far, `AutoBuild` has nothing of the sort.
This PR proposes to introduce an environment variable `LGTM_INDEX_FILETYPES` to allow a similar customisation. In the fullness of time, this variable would be set through `lgtm.yml` in the usual way, but for now it is undocumented and for internal use only.
Specifically, `LGTM_INDEX_FILETYPES` is a newline-separated list of ".extension:filetype" pairs, specifying that files with the given `.extension` should be extracted as type `filetype`, where
`filetype` is one of `js`, `html`, `json`, `typescript` or `yaml`.
For example, `.jsm:js` causes all `.jsm` files to be extracted as JavaScript.
This can also be used to override default file types: for example, by specifying `.js:typescript` all JavaScript files will be extracted as TypeScript.
