tmux resolves the two halves of a target with different, individually
dangerous defaults, and send-message.sh took both defaults:
* An unpinned name PREFIX-matches. With `foobar` alive and no `foo`,
`-t foo` resolves to `foobar` at rc=0 -- pasted, Enter-ed, verified
and reported OK against the wrong agent's pane.
* A bare `=name` is only half a pin. capture-pane REJECTS it ("can't
find pane") while list-panes silently PREFIX-MATCHES it, and the
validation at :76 uses list-panes -- so for any caller already
supplying `=name`, that rewrite was the only thing between them and
a wrong-session pass.
The direction is what makes this expensive. Paste (:93-94), Enter (:151)
and the verifying capture (:153) all read one EFFECTIVE_TARGET, so a
wrong-window send is confirmed by a wrong-window read: it manufactures a
false "delivered", not a loud failure. A false negative gets
investigated; a false positive gets believed.
Normalise to `=session:` -- exact session, active window. Explicit tmux
ids (%pane, @window, $session) pass through untouched.
BEHAVIOUR CHANGE for callers that already pass `=name`: they previously
landed on `:0.0` (window 0 unconditionally) and now land on the session's
ACTIVE window. This is the intended fix -- window 0 is not where a
multi-window agent is sitting -- but it does move a live target rather
than being a no-op normalisation.
Test: test-send-message-target.sh covers all four arms (absent name must
not prefix-match, delivery follows the active window, an explicit window
part is preserved, a unique prefix is still refused). Proven able to go
red: against the pre-fix script it FAILs at arm 1, and with arm 1 removed
it FAILs at arm 2. The multi-window fixture is load-bearing -- a
single-window session cannot tell `=s:` from `=s:0.0`, which is why this
survived.
It is registered as a signed enumeration exclusion rather than on a CI
surface: it drives a real tmux server and the CI image ships no tmux,
the same condition its two siblings are already excluded under. It
hard-fails when tmux is absent rather than skipping, so it cannot go
quietly green where it cannot run.
jarvis-enhance
a77afe6778