dir function not available in pug evaluation context?

[MartijnR]

as discussed here: https://www.flowdock.com/app/kobotoolbox/enketo/threads/6SNVMAR_i9rztcVzF14rdE5GYP3

20:34:21 0|enketo  | TypeError: /srv/src/enketo_express/app/views/layout.pug:2
20:34:21 0|enketo  |     1| doctype html
20:34:21 0|enketo  |   > 2| html(manifest=manifest, lang=language, dir=dir(language))
20:34:21 0|enketo  |     3|   head
20:34:21 0|enketo  |     4|     title= title
20:34:21 0|enketo  |     5|
20:34:21 0|enketo  | dir is not a function
20:34:21 0|enketo  |     at eval (eval at wrap (/srv/src/enketo_express/node_modules/pug-runtime/wrap.js:6:10), <anonymous>:6:137)
20:34:21 0|enketo  |     at template (eval at wrap (/srv/src/enketo_express/node_modules/pug-runtime/wrap.js:6:10), <anonymous>:149:72)
20:34:21 0|enketo  |     at Object.exports.renderFile (/srv/src/enketo_express/node_modules/pug/lib/index.js:427:38)
20:34:21 0|enketo  |     at Object.exports.renderFile (/srv/src/enketo_express/node_modules/pug/lib/index.js:417:21)
20:34:21 0|enketo  |     at View.exports.__express [as engine] (/srv/src/enketo_express/node_modules/pug/lib/index.js:464:11)
20:34:21 0|enketo  |     at View.render (/srv/src/enketo_express/node_modules/express/lib/view.js:135:8)
20:34:21 0|enketo  |     at tryRender (/srv/src/enketo_express/node_modules/express/lib/application.js:640:10)
20:34:21 0|enketo  |     at Function.render (/srv/src/enketo_express/node_modules/express/lib/application.js:592:3)
20:34:21 0|enketo  |     at ServerResponse.render (/srv/src/enketo_express/node_modules/express/lib/response.js:1008:7)
20:34:21 0|enketo  |     at production (/srv/src/enketo_express/app/controllers/error-handler.js:32:17)

[MartijnR]

it is supposed to be exposed here: https://github.com/enketo/enketo-express/blob/master/config/express.js#L92

Try to reproduce by making an /instance/ api call if not immediately reproducible when loading an empty form.