feed: notification feed — per-recipient inbox, verb filter, (verb,object) digest + 8 tests

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

lib/feed/tests/notify.sx

@@ -0,0 +1,69 @@
+; Follow-up — notification feed over an inbox. (feed-test name got expected)
+
+; an inbox is a stream of {:to receiver :activity act} events
+(define mk-ev (fn (to act) {:activity act :to to}))
+
+(define
+  IB
+  (feed/stream
+    (list
+      (mk-ev "alice" (feed/activity "bob" "like" "P" 10 (list)))
+      (mk-ev "alice" (feed/activity "carol" "like" "P" 20 (list)))
+      (mk-ev "alice" (feed/activity "dave" "reply" "Q" 30 (list)))
+      (mk-ev "bob" (feed/activity "eve" "like" "R" 40 (list))))))
+
+; ---------- raw notifications ----------
+
+(feed-test
+  "alice notification count"
+  (feed/count (feed/notifications IB "alice"))
+  3)
+(feed-test
+  "bob notification count"
+  (feed/count (feed/notifications IB "bob"))
+  1)
+(feed-test
+  "zoe no notifications"
+  (feed/count (feed/notifications IB "zoe"))
+  0)
+
+; ---------- verb filtering ----------
+
+(feed-test
+  "alice likes only"
+  (feed/count (feed/notify-verbs IB "alice" (list "like")))
+  2)
+(feed-test
+  "alice replies only"
+  (feed/count (feed/notify-verbs IB "alice" (list "reply")))
+  1)
+(feed-test
+  "alice like+reply"
+  (feed/count (feed/notify-verbs IB "alice" (list "like" "reply")))
+  3)
+(feed-test
+  "alice follow (none)"
+  (feed/count (feed/notify-verbs IB "alice" (list "follow")))
+  0)
+
+; ---------- digest ----------
+
+(define dig (feed/notify-digest IB "alice"))
+
+(feed-test "digest group count" (len dig) 2)
+(feed-test
+  "digest sorted by key (like|P before reply|Q)"
+  (map (fn (g) (get g :object)) dig)
+  (list "P" "Q"))
+(feed-test
+  "like group actors"
+  (get (nth dig 0) :actors)
+  (list "bob" "carol"))
+(feed-test "like group count" (get (nth dig 0) :count) 2)
+(feed-test "like group verb" (get (nth dig 0) :verb) "like")
+(feed-test "reply group count" (get (nth dig 1) :count) 1)
+(feed-test
+  "reply group actors"
+  (get (nth dig 1) :actors)
+  (list "dave"))
+(feed-test "empty digest for zoe" (feed/notify-digest IB "zoe") (list))