FilterWithoutEffect

Last edit: Aug 16, 2026

FilterWithoutEffect

Severity: warning | Type: LiquidHtml

This check reports a filter written somewhere the platform silently ignores it.

The deploy converter accepts the file and nothing raises. platformOS parses a tag's markup with its own scanner, which does not apply filters — so the value arrives unfiltered and the page renders with the wrong data. That silence is what makes it worth a check: there is no error to trace back.

Examples

✗ Incorrect Code Example (Avoid using this):


{% cache 'key' | upcase %}
  body
{% endcache %}

The cache key is key, not KEY. The filter is parsed as part of the markup and discarded.

✓ Correct Code Example (Use this instead):


{% assign k = 'key' | upcase %}
{% cache k %}
  body
{% endcache %}

Apply the filter in an {% assign %} and pass the assigned variable.

Where filters DO apply

A filter works where the whole value is a Liquid variable:

output and assignment — {{ … }}, {% assign %}, {% echo %}, {% print %}, {% return %}, {% session %};
an argument whose value is a JSON literal — {% log 'm', data: {"a": 1} | json %};
a trailing filter after {% graphql res = 'file' %}, which filters the result.

A trailing filter on {% function %} or {% background %}, or on the inline {% graphql %} block, only looks like that last case and is discarded — filter the result in a following {% assign %} instead.

Configuration

The default configuration for this check:

FilterWithoutEffect:
  enabled: true
  severity: warning

Disabling This Check

Disabling this check is not recommended. Nothing else reports it: the file deploys, the page renders, and the only symptom is a value that was never filtered.

FilterWithoutEffect