Fix bug causing queryRenderedFeatures to crash on polygon features that have an id field.

[gmaclennan]

mapbox-gl-js version: v0.34.0

Steps to Trigger Behavior

1. Add a GeoJSON polygon source with non-integer (string) ids
2. Call map.queryRenderedFeatures() on mousemove

Expected Behavior

map.queryRenderedFeatures() should return an array of features under the mouse pointer

Actual Behavior

Uncaught Error: Unimplemented type: 7

I have created a JSFiddle of the failing code: https://jsfiddle.net/p78o8exf/6/

This code works fine with v0.32.1 but since v0.33 it is broken. This is valid GeoJSON (checked with @mapbox/geojsonhint).

[jfirebaugh]

@gmaclennan I'm seeing "Uncaught ReferenceError: dataIndex is not defined" when loading that JSFiddle, which seems to be preventing it from getting to the subsequent error. Can you take a look?

[gmaclennan]

@jfirebaugh thanks for following up, my apologies, I forgot to save changes as I was removing unrelated code. try here: https://jsfiddle.net/p78o8exf/3/

[gmaclennan]

Here is the data source: https://github.com/digidem/alianza-ceibo-maps/blob/gh-pages/data.json

[gmaclennan]

One more piece of information: I tried filtering the geojson to only show features with geometry.type === 'Polygon' or MultiPolygon and I get the same error with each, well, I get a different unimplemented type: 4

[indus]

Maybe the array properties? https://www.mapbox.com/vector-tiles/specification/#how-to-encode-attributes-that-arent-strings-or-numbers

[jfirebaugh]

Can you reduce the test case further, e.g. remove everything that's not essential to triggering the bug from the GeoJSON?

[gmaclennan]

Ok, more pairing down done now, and I found the cause of the bug:
https://jsfiddle.net/p78o8exf/6/
It is triggered by leaving the id on the feature. Removing that fixes it.

[anandthakker]

@gmaclennan thanks for isolating it!

Looks like the problem is that the feature.ids are strings here, which we currently don't handle correctly (it's a vestige of the fact that the vector tile spec only allows integer IDs, and GeoJSON sources share some implementation details with vector tile sources). Changing id to, e.g., Math.floor(Math.random() * 1000) prevents the crash.

This is being tracked at #2716, although the test case here demonstrates that (polygon) layers manifest the bug more severely -- crashing rather than simply stripping out the id.

Closing in favor of 2716

[anandthakker]

Reopening here to track the crashing bug, which @gmaclennan rightly pointed out is distinct from #2716, which is an enhancement.