Scenario: a splice path must be ref-friendly

A splice path must be valid in a Git ref name, e.g. without spaces, so git splice clone rejects such a path before it fetches anything. Paths used to be part of the splice's ref names. Since refs are keyed by the upstream's URL, the limit only remains until every command is tested with such paths.

Output

setup.bash builds the same empty monorepo as the other document in this folder:

$ build_scenario scenario_clone_without_commits

The first command gives it the commit this example needs:

$ git commit -q --allow-empty -m "initial commit" && git splice clone "$UPSTREAM" "my lib"
!!   'my lib' isn't supported as a splice path yet -- choose another folder name (e.g. no spaces)
[1]

No splice refs were created:

$ git for-each-ref --format='%(refname)' refs/splices