Given the following: ```yaml parts: my-part: build-packages: - to armhf: - foo - to riscv64: - bar - else: - baz ``` Building for armhf will evaluate to `["foo", "baz"]` and building for riscv64 will evaluate to `["bar"]`. This is an unexpected UX and there are no warnings or errors to explain the behavior. Either craft-grammar should error when given multiple `to` statements with an `else` or it should properly handle this scenario. A reproducer in the unit test suite can be seen here: https://github.com/canonical/craft-grammar/commit/12c031a207eaec4e1c345ad8a9ad2444ec4429ae Source: https://github.com/canonical/snapcraft/issues/5255