Filters

Cargo Feature: filters

Similar to redactions insta also supports filtering of snapshots. These are regular expressions applied to the actual snapshot content to normalize input before they are persisted to disk. Filters are an optional feature and can be enabled with the filters feature.

Filters can be only defined via settings. They are individually added with Settings::add_filter or by using the with_settings! macro. The first argument is the regex, the second is the replacement string. When set with with_settings! a vector of tuples is expected:

insta::with_settings!({filters => vec![
    (r"\b[[:xdigit:]]{32}\b", "[UID]"),
]}, {
    insta::assert_snapshot!(...);
});

Filters are useful when redactions cannot be used because the snapshot is inherently in a string format.