Compatibility rules, before resolution

The registry stores rules, not one row per pair. A rule side is one of four patterns, from least to most specific: "*" for any feature (specificity 0), "kind:<kind>" for a whole kind (1), "group:<group>" for a named feature set (2), or a bare feature name (3).

Usage

frm_compat_rules()

Value

A data frame with columns feature_a, feature_b, status, note, and override.

Details

A pair takes the status of the rule with the highest precedence, where precedence is the two sides' specificities sorted descending and compared lexicographically: (3,3) beats (3,2) beats (3,1) beats (3,0) beats (2,2) beats (2,1), and so on. A rule that is strictly more specific on one side and no less specific on the other therefore always wins. Rules can tie only when their two specificities match exactly; the later rule wins those, so an override is appended rather than inserted, and a tie between rules that disagree about the status is a registry defect the test suite rejects.

Use frm_compat() to read the resolved answer for a pair. Use this function to see which rule is doing the work.

See also

frm_compat(), frm_compat_features()

Examples

rules <- frm_compat_rules()
nrow(rules)
#> [1] 866
subset(rules, status == "broken")[, c("feature_a", "feature_b")]
#> [1] feature_a feature_b
#> <0 rows> (or 0-length row.names)