Filter expression using 'all' with ['zoom'] and property doesn't work as expected

[jlocus]

mapbox-gl-js version: 0.41.0

Steps to Trigger Behavior

1. Start from the "Final Product" example here: https://www.mapbox.com/help/mapbox-gl-js-expressions/

2. Modify the code to add a 'Filter' clause using both the 'Constructi' property and ['zoom']:

   'filter': ['all', ['>=', 'Constructi', 1930], ['>=', ['zoom'], 10]]

Example at: https://jsbin.com/losiwikipa/edit?html,output

Expected Behavior

Red circles should appear for items constructed after 1930 when the zoom level is >= 10

Actual Behavior

No red circles appear under any circumstances

These "all" clauses both work as expected:'

'filter': ['all', ['>=', 'Constructi', 1930], ['>=', 'Constructi', 1930]]
'filter': ['all', ['>=', ['zoom'], 10], ['>=', ['zoom'], 10]]

[jfirebaugh]

Hi @jlocus, thanks for the report! There is indeed an issue here: the filter ['all', ['>=', 'Constructi', 1930], ['>=', ['zoom'], 10]] is invalid, and should have produced a validation error. I believe what you wanted was ['all', ['>=', ['number', ['get', 'Constructi']], 1930], ['>=', ['zoom'], 10]] -- note the use of number and get expressions as shown in the help guide. I've opened a PR that tightens up the validation to catch issues like this in the future.

(Also note that you can't mix the old filter syntax and new expression syntax in the same filter -- if the filter uses any new expression syntax, then the whole thing must be a valid expression.)