query*Features and MapMouseEvent.features returns a null feature property as "null"

[nrako]

mapbox-gl-js version: v1.1.1 (true for previous versions too)

browser: Chrome ...

Link to Demonstration

https://codepen.io/anon/pen/rXBGBb?editors=1001#anon-login

Expected Behavior

I would expect a returned value of property on a geojson feature to remain null and not become "null".

Actual Behavior

A null property geojson feature e.g{ my_property: null } is converted to a string { my_property: 'null' } when queried (i.e querySourceFeatures) or in MapMouseEvent's features.

By inspecting the _data of the source I can see that null values of feature properties are stored as expected.

[jbelien]

Same issue with version 1.8.1 (with same use case : GeoJSON file feature queried through a click on map).

[cafca]

Can somebody with knowledge of the codebase comment where source / solution of this bug could be found? I may be able to create a PR if given a hint.

[rdmurphy]

Wanted to flag that this is still an issue that I just hit.

[porsager]

Thought I would add that this PR fixes this issue if it's merged: mapbox/vt-pbf#39

[strech345]

can please someone check this pr?

[friendlyswiss]

Just flagging that I'm still running into this issue.

[andrewharvey]

copypaste workaround if you know your data has not actual string values called "null"

const features = map.queryRenderedFeatures(...)
for (let i = 0; i < features.length; i++) {
  for (const key of Object.keys(features[i].properties)) {
    if (features[i].properties[key] === 'null') {
      features[i].properties[key] = null
    }
  }
}