Filter Widget "None" filter breaks Feature Grid WFS (CQL -> OGC null parsing)

[rowheat02]

Description

Dynamic filtering from the Filter Widget (None condition) fails only in Feature Grid/WFS flow.

The same CQL works in WMS (GeoServer CQL_FILTER), but fails in WFS because internal CQL -> OGC conversion in MapStore does not handle this null-filter expression correctly.

CQL is generated by:

• toCQLFilter in /web/client/utils/FilterUtils.js

toCQLFilter generates the filter text, but parser/converter handling in WFS path breaks, so no WFS request is sent by Feature Grid.

How to reproduce

• Open map: https://dev-mapstore.geosolutionsgroup.com/mapstore/#/viewer/64442

• Create/activate a user-defined filter with None condition in Filter Widget

• Open Feature Grid (attribute table) for the same layer

  Screen.Recording.2026-03-03.at.13.27.18.mov

Expected Result
Feature Grid sends WFS request and shows filtered records.

Current Result
Feature Grid shows no features and no WFS request is sent. Console shows parse/convert errors from wfsQueryEpic, e.g.:

Error in epic "wfsQueryEpic". Original error: Error: ERROR: In parsing: [(isNull("budgetx1")=true))], expected one of: 
    COMPARISON: /^(=|<>|<=|<|>=|>|LIKE|ILIKE)/i
    BETWEEN: /^BETWEEN/i
    COMMA: /^,/
    IS_NULL: /^IS NULL/i
    RPAREN: /^\)/
Uncaught Error: ERROR: In parsing: [(isNull("budgetx1")=true))], expected one of:

COMPARISON: /^(=|<>|<=|<|>=|>|LIKE|ILIKE)/i

BETWEEN: /^BETWEEN/i

COMMA: /^,/

IS_NULL: /^IS NULL/i

• Not browser related