jackfirth / resyntax / #414

94%

master: 94%

push

cover

Make source groups unionable

Source groups now form a commutative monoid: source-group-union
combines any number of groups into one, and empty-source-group is the
identity element. Since unioning is also idempotent, they're in fact a
bounded join-semilattice. The laws hold up to equal?, which is achieved
by an internal union-source-group struct that holds a normalized set of
non-union subgroups: flattening makes union associative, set semantics
make it commutative and idempotent, and collapsing singleton and empty
sets makes the identity law hold exactly rather than up to wrapping.

Consequently, source-groups-resolve is now source-group-resolve and
takes a single group; the CLI unions its target flags into one group
before resolving.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

49 of 55 new or added lines in 3 files covered. (89.09%)

15870 of 16907 relevant lines covered (93.87%)

0.94 hits per line