bud panels duplicate-add guard: server-side already_present flag + client-side error Brief w. FYI flash highlight on the existing entry — for each of the three #id_bud_btn panels (My Buds / post-share / gatekeeper-invite), the JSON response from add_bud / share_post / invite_gamer now carries {already_present, recipient_display, recipient_user_id}; bud-btn.js branches on already_present → calls new Brief.showDuplicateBanner({display_name, target_selector}) instead of the normal onSuccess append; banner title reads @<username> is already present, NVM dismisses, FYI dismisses AND eases in the .bud-duplicate-flash class (color: var(--terUser); text-shadow: 0 0 .5em var(--ninUser); transition: 600ms) onto the existing element (.bud-entry .bud-name / .post-recipient[data-user-id=…] / .gate-slot.filled[data-user-id=…]); gatekeeper "already present" = recipient is either GateSlot.FILLED + gamer OR has TableSeat OR has a pending RoomInvite (highlight target only set when seated — pending invites have no visible slot); .post-recipient chips + .gate-slot.filled cells gain data-user-id so the FYI selector can find them; my_buds.html now loads note.js via the {% block scripts %} pattern (Brief module is required by the duplicate banner path); bonus: latent test_jasmine.py bug fixed — "0 failures" in result.text matched "10 failures" / "20 failures" / etc, silently passing up to 99 failed specs; replaced w. re.search(r"(?<!\d)0 failures\b", …) (caught my new red specs, would've caught any prior Jasmine regression); 18 new ITs + 10 new Jasmine specs + 3 new FTs (one per panel) — TDD

Code architected by Disco DeDisco <discodedisco@outlook.com>
Git commit message Co-Authored-By:
Claude Opus 4.7 (1M context) <noreply@anthropic.com>

src/apps/billboard/static/apps/billboard/bud-btn.js

@@ -4,12 +4,23 @@
 //   • _bud_add_panel.html    — My Buds add       (POSTs to billboard:add_bud)
 //
 // Owns: csrf cookie read, open/close + .bud-open html-class, button click,
-// Escape, click-outside, Enter-in-input, OK POST + JSON routing.
+// Escape, click-outside, Enter-in-input, OK POST + JSON routing, and the
+// `data.already_present` duplicate-guard branch (error Brief instead of
+// the normal onSuccess append).
 //
-// Each caller drives it with `bindBudBtn({submitUrl, autocompleteUrl?, onSuccess})`.
-// `onSuccess(data)` does the panel-specific DOM updates (line append, chip
-// append, bud-entry append, Brief banner — whatever the response carries).
-// _close({clear: true}) fires automatically on a successful response.
+// Each caller drives it with:
+//   bindBudBtn({
+//     submitUrl,
+//     autocompleteUrl?,
+//     onSuccess(data),                    // success path: line/chip/entry/Brief
+//     duplicateTargetSelector?(data),     // selector for .bud-duplicate-flash
+//   })
+//
+// `onSuccess(data)` does the panel-specific DOM updates on the new-row path.
+// `duplicateTargetSelector(data)` returns a CSS selector for the existing
+// element to highlight when the FYI button on the error Brief is clicked
+// (.bud-name / .post-recipient / .gate-slot.filled — varies by page).
+// _close({clear: true}) fires automatically on every successful response.
 //
 // `autocompleteUrl` enables bud-autocomplete on the input (post-share +
 // gatekeeper panels) by binding bud-autocomplete.js to #id_bud_suggestions.
@@ -87,7 +98,21 @@
             })
                 .then(function (r) { return r.ok ? r.json() : Promise.reject(r.status); })
                 .then(function (data) {
-                    if (typeof opts.onSuccess === 'function') opts.onSuccess(data);
+                    if (data && data.already_present) {
+                        // Skip onSuccess — there's nothing to append. Show the
+                        // error Brief instead. target_selector resolves at call
+                        // time from the caller's per-page callback.
+                        if (window.Brief) {
+                            var sel = (typeof opts.duplicateTargetSelector === 'function')
+                                ? opts.duplicateTargetSelector(data) : null;
+                            Brief.showDuplicateBanner({
+                                display_name:    data.recipient_display,
+                                target_selector: sel,
+                            });
+                        }
+                    } else if (typeof opts.onSuccess === 'function') {
+                        opts.onSuccess(data);
+                    }
                     _close({ clear: true });
                 })
                 .catch(function () {

src/apps/billboard/tests/integrated/test_buds.py

@@ -239,3 +239,84 @@ class SharePostImplicitAutoAddTest(TestCase):
         """Privacy: unregistered email doesn't touch the buds graph."""
         self._share("ghost@test.io")
         self.assertEqual(self.sharer.buds.count(), 0)
+
+
+class AddBudAlreadyPresentTest(TestCase):
+    """Duplicate-add guard: add_bud's JSON response distinguishes "newly
+    added" from "already a bud" so the bud-btn JS can render an error
+    Brief titled `@<username> is already present` instead of the normal
+    bud-entry append. `recipient_user_id` is the highlight target id that
+    the Brief FYI button toggles `.bud-duplicate-flash` onto."""
+
+    def setUp(self):
+        self.user = User.objects.create(email="me@test.io", username="me")
+        self.client.force_login(self.user)
+        self.alice = User.objects.create(email="alice@test.io", username="alice")
+        self.user.buds.add(self.alice)
+
+    def _add(self, recipient):
+        return self.client.post(
+            reverse("billboard:add_bud"), {"recipient": recipient},
+        )
+
+    def test_already_present_true_when_candidate_is_already_a_bud(self):
+        self.assertTrue(self._add("alice@test.io").json()["already_present"])
+
+    def test_already_present_false_for_new_bud(self):
+        User.objects.create(email="bob@test.io", username="bob")
+        self.assertFalse(self._add("bob@test.io").json()["already_present"])
+
+    def test_already_present_false_for_unregistered_email(self):
+        self.assertFalse(self._add("ghost@test.io").json()["already_present"])
+
+    def test_recipient_display_carries_username_on_duplicate(self):
+        self.assertEqual(self._add("alice@test.io").json()["recipient_display"], "alice")
+
+    def test_recipient_user_id_carries_alice_id_on_duplicate(self):
+        self.assertEqual(
+            self._add("alice@test.io").json()["recipient_user_id"],
+            str(self.alice.id),
+        )
+
+    def test_username_typed_recipient_also_detects_duplicate(self):
+        """A user typing 'alice' (no @) resolves the same way as the email."""
+        self.assertTrue(self._add("alice").json()["already_present"])
+
+
+class SharePostAlreadyPresentTest(TestCase):
+    """Duplicate-share guard mirrors AddBudAlreadyPresentTest — when the
+    recipient is already in post.shared_with, response carries
+    already_present + recipient_user_id for the .post-recipient highlight."""
+
+    def setUp(self):
+        from apps.billboard.models import Post
+        self.sharer = User.objects.create(email="sharer@test.io", username="sharer")
+        self.client.force_login(self.sharer)
+        self.alice = User.objects.create(email="alice@test.io", username="alice")
+        self.post = Post.objects.create(owner=self.sharer)
+        self.post.shared_with.add(self.alice)
+
+    def _share(self, recipient):
+        return self.client.post(
+            reverse("billboard:share_post", args=[self.post.id]),
+            data={"recipient": recipient},
+            HTTP_ACCEPT="application/json",
+        )
+
+    def test_already_present_true_when_recipient_in_shared_with(self):
+        self.assertTrue(self._share("alice@test.io").json()["already_present"])
+
+    def test_already_present_false_for_new_recipient(self):
+        User.objects.create(email="bob@test.io", username="bob")
+        self.assertFalse(self._share("bob@test.io").json()["already_present"])
+
+    def test_recipient_user_id_present_on_duplicate(self):
+        self.assertEqual(
+            self._share("alice@test.io").json()["recipient_user_id"],
+            str(self.alice.id),
+        )
+
+    def test_recipient_display_already_present_on_duplicate(self):
+        """`recipient_display` already exists on the success path; on
+        duplicate the same field must carry the matched user's handle."""
+        self.assertEqual(self._share("alice@test.io").json()["recipient_display"], "alice")

src/apps/billboard/views.py

@@ -392,12 +392,16 @@ def share_post(request, post_id):
         # list exposes; doesn't widen the privacy surface beyond what the
         # post detail page already shows publicly.
         recipient_display = None
+        recipient_user_id = None
         if recipient is not None:
             recipient_display = recipient.username or recipient.email
+            recipient_user_id = str(recipient.id)
         return JsonResponse({
             "brief":             brief.to_banner_dict() if brief is not None else None,
             "line_text":         line_text,
             "recipient_display": recipient_display,
+            "recipient_user_id": recipient_user_id,
+            "already_present":   is_reshare,
         })
 
     messages.success(request, "An invite has been sent if that address is registered.")
@@ -446,16 +450,28 @@ def add_bud(request):
     candidate = _resolve_recipient(request.POST.get("recipient"))
 
     bud = None
+    already_present = False
+    recipient_display = None
+    recipient_user_id = None
     if candidate is not None and candidate != request.user:
-        if candidate not in request.user.buds.all():
+        already_present = candidate in request.user.buds.all()
+        if not already_present:
             request.user.buds.add(candidate)
+        display = candidate.username or candidate.email
         bud = {
             "id":       str(candidate.id),
-            "username": candidate.username or candidate.email,
+            "username": display,
             "email":    candidate.email,
         }
+        recipient_display = display
+        recipient_user_id = str(candidate.id)
 
-    return JsonResponse({"bud": bud})
+    return JsonResponse({
+        "bud":               bud,
+        "already_present":   already_present,
+        "recipient_display": recipient_display,
+        "recipient_user_id": recipient_user_id,
+    })
 
 
 @login_required(login_url="/")

src/apps/dashboard/static/apps/dashboard/note.js

@@ -69,13 +69,54 @@ const Brief = (() => {
         showBanner(data && data.brief);
     }
 
+    // Error-variant banner for "@<username> is already present". Distinct
+    // from showBanner because it's purely client-side (no Brief DB row);
+    // title carries the recipient handle; there's no date/square/post_url;
+    // FYI is a <button> (no navigation) that toggles `.bud-duplicate-flash`
+    // onto a caller-supplied target element + dismisses. NVM just dismisses.
+    function showDuplicateBanner(opts) {
+        if (!opts || !opts.display_name) return;
+
+        var banner = document.createElement('div');
+        banner.className = 'note-banner note-banner--duplicate';
+        banner.innerHTML =
+            '<div class="note-banner__body">' +
+                '<p class="note-banner__title">@' + _esc(opts.display_name) + ' is already present</p>' +
+            '</div>' +
+            '<button type="button" class="btn btn-cancel note-banner__nvm">NVM</button>' +
+            '<button type="button" class="btn btn-info note-banner__fyi">FYI</button>';
+
+        banner.querySelector('.note-banner__nvm').addEventListener('click', function () {
+            banner.remove();
+        });
+        banner.querySelector('.note-banner__fyi').addEventListener('click', function () {
+            if (opts.target_selector) {
+                var target = document.querySelector(opts.target_selector);
+                if (target) target.classList.add('bud-duplicate-flash');
+            }
+            banner.remove();
+        });
+
+        var anchor = document.getElementById('id_brief_banner_anchor')
+                  || document.querySelector('h2');
+        if (anchor && anchor.parentNode) {
+            anchor.parentNode.insertBefore(banner, anchor.nextSibling);
+        } else {
+            document.body.insertBefore(banner, document.body.firstChild);
+        }
+    }
+
     function _esc(str) {
         var d = document.createElement('div');
         d.textContent = str || '';
         return d.innerHTML;
     }
 
-    return { showBanner: showBanner, handleSaveResponse: handleSaveResponse };
+    return {
+        showBanner:          showBanner,
+        showDuplicateBanner: showDuplicateBanner,
+        handleSaveResponse:  handleSaveResponse,
+    };
 })();
 
 // Backwards-compat shim — to be removed once the codebase uniformly uses Brief.

src/apps/epic/tests/integrated/test_invite_gamer.py

@@ -141,3 +141,88 @@ class InviteGamerLegacyFormTest(TestCase):
         self.assertTrue(RoomInvite.objects.filter(
             room=self.room, invitee_email="alice@test.io",
         ).exists())
+
+
+class InviteGamerAlreadyPresentTest(TestCase):
+    """Duplicate-invite guard: a gatekeeper invite gets `already_present:
+    true` in its JSON response when the recipient is either (a) already
+    seated in the room or (b) has a pending RoomInvite. `recipient_user_id`
+    is set only when seated — pending invitees have no visible
+    `.gate-slot.filled` DOM element to highlight, so the FYI button just
+    dismisses without easing in the flash class."""
+
+    def setUp(self):
+        from apps.epic.models import GateSlot, TableSeat
+        self.GateSlot = GateSlot
+        self.TableSeat = TableSeat
+        self.owner = User.objects.create(email="owner@test.io", username="owner")
+        self.client.force_login(self.owner)
+        self.alice = User.objects.create(email="alice@test.io", username="alice")
+        self.room = Room.objects.create(name="Bingo", owner=self.owner)
+
+    def _invite(self, recipient):
+        return self.client.post(
+            reverse("epic:invite_gamer", args=[self.room.id]),
+            data={"recipient": recipient},
+            HTTP_ACCEPT="application/json",
+        )
+
+    def test_already_present_true_when_recipient_is_seated_via_gate_slot(self):
+        """Gatekeeper phase: 'seated' means a GateSlot.FILLED w. gamer set."""
+        self.GateSlot.objects.create(
+            room=self.room, gamer=self.alice, slot_number=1,
+            status=self.GateSlot.FILLED,
+        )
+        self.assertTrue(self._invite("alice@test.io").json()["already_present"])
+
+    def test_already_present_true_when_recipient_has_table_seat(self):
+        """Post-gatekeeper phase: TableSeat exists once slots transition."""
+        self.TableSeat.objects.create(room=self.room, gamer=self.alice, slot_number=1)
+        self.assertTrue(self._invite("alice@test.io").json()["already_present"])
+
+    def test_recipient_user_id_carries_alice_id_when_seated(self):
+        self.TableSeat.objects.create(room=self.room, gamer=self.alice, slot_number=1)
+        body = self._invite("alice@test.io").json()
+        self.assertEqual(body["recipient_user_id"], str(self.alice.id))
+
+    def test_already_present_true_when_recipient_has_pending_room_invite(self):
+        RoomInvite.objects.create(
+            room=self.room, inviter=self.owner,
+            invitee_email="alice@test.io", status=RoomInvite.PENDING,
+        )
+        self.assertTrue(self._invite("alice@test.io").json()["already_present"])
+
+    def test_recipient_user_id_null_when_only_invited_not_seated(self):
+        """Pending invites have no visible slot element to highlight."""
+        RoomInvite.objects.create(
+            room=self.room, inviter=self.owner,
+            invitee_email="alice@test.io", status=RoomInvite.PENDING,
+        )
+        self.assertIsNone(self._invite("alice@test.io").json()["recipient_user_id"])
+
+    def test_already_present_false_for_brand_new_recipient(self):
+        self.assertFalse(self._invite("alice@test.io").json()["already_present"])
+
+    def test_brief_is_null_on_duplicate(self):
+        """No new Brief on duplicate — the client renders the error Brief
+        from the already_present flag instead."""
+        self.TableSeat.objects.create(room=self.room, gamer=self.alice, slot_number=1)
+        self.assertIsNone(self._invite("alice@test.io").json()["brief"])
+
+    def test_no_new_room_invite_on_duplicate(self):
+        RoomInvite.objects.create(
+            room=self.room, inviter=self.owner,
+            invitee_email="alice@test.io", status=RoomInvite.PENDING,
+        )
+        self._invite("alice@test.io")
+        self.assertEqual(
+            RoomInvite.objects.filter(room=self.room, invitee_email="alice@test.io").count(),
+            1,
+        )
+
+    def test_recipient_display_carries_username_on_duplicate(self):
+        self.TableSeat.objects.create(room=self.room, gamer=self.alice, slot_number=1)
+        self.assertEqual(
+            self._invite("alice@test.io").json()["recipient_display"],
+            "alice",
+        )

src/apps/epic/views.py

@@ -699,21 +699,43 @@ def invite_gamer(request, room_id):
     # username-typed invite doesn't store the raw username as if it were
     # an email); falls back to the raw input for unregistered addresses.
     invitee_email = candidate.email if candidate else raw
-    RoomInvite.objects.get_or_create(
+
+    # Duplicate-invite guard: "already present" = recipient is either
+    # already seated in the room OR has a (pending/accepted) RoomInvite.
+    # During gatekeeper phase the visible `.gate-slot.filled` cells are
+    # GateSlot-driven (TableSeats spin up later at SIG SELECT), so check
+    # both — GateSlot.FILLED catches the in-phase case, TableSeat catches
+    # the post-phase case. Seated recipients carry recipient_user_id so
+    # the client can find the .gate-slot.filled[data-user-id="X"]
+    # highlight target; pending invitees have no visible slot, so
+    # recipient_user_id stays null.
+    already_seated = candidate is not None and (
+        GateSlot.objects.filter(
+            room=room, gamer=candidate, status=GateSlot.FILLED,
+        ).exists()
+        or TableSeat.objects.filter(room=room, gamer=candidate).exists()
+    )
+    already_invited = RoomInvite.objects.filter(
+        room=room, invitee_email=invitee_email,
+    ).exists()
+    already_present = already_seated or already_invited
+
+    brief = None
+    if not already_present:
+        RoomInvite.objects.create(
             room=room,
             inviter=request.user,
             invitee_email=invitee_email,
-        defaults={"status": RoomInvite.PENDING},
+            status=RoomInvite.PENDING,
         )
-
         # Buds graph: symmetric auto-add on registered recipients (mirrors
         # share_post). Idempotent on M2M; no-op on unregistered recipients.
         if candidate is not None:
             request.user.buds.add(candidate)
             candidate.buds.add(request.user)
-
-    # Brief: confirmation banner for the inviter. Brief.post stays null;
-    # banner FYI navigates to the room's gatekeeper page via Brief.room.
+        # Brief: confirmation banner for the inviter. Brief.post stays
+        # null; banner FYI navigates to the room's gatekeeper page via
+        # Brief.room.
         brief = Brief.objects.create(
             owner=request.user,
             post=None,
@@ -722,13 +744,17 @@ def invite_gamer(request, room_id):
             title="Invite sent",
         )
 
+    recipient_user_id = str(candidate.id) if already_seated else None
+
     if is_ajax:
         recipient_display = None
         if candidate is not None:
             recipient_display = candidate.username or candidate.email
         return JsonResponse({
-            "brief":             brief.to_banner_dict(),
+            "brief":             brief.to_banner_dict() if brief is not None else None,
             "recipient_display": recipient_display,
+            "recipient_user_id": recipient_user_id,
+            "already_present":   already_present,
         })
 
     return redirect("epic:gatekeeper", room_id=room_id)

src/functional_tests/test_bud_btn.py

@@ -379,3 +379,49 @@ class PostHtmlAperturePageClassTest(FunctionalTest):
             "page-billboard" in cls or "page-billpost" in cls,
             f"my_posts.html body class missing aperture marker: {cls!r}",
         )
+
+
+class BudBtnDuplicateShareErrorTest(FunctionalTest):
+    """Re-sharing a post w. someone already in post.shared_with triggers
+    the error Brief titled `@<username> is already present`. FYI on the
+    Brief dismisses + adds .bud-duplicate-flash to the existing
+    .post-recipient[data-user-id=…] chip."""
+
+    def setUp(self):
+        super().setUp()
+        self.sharer = User.objects.create(email="bud@test.io", username="bud")
+        self.alice = User.objects.create(email="alice@test.io", username="alice")
+        self.post = _seed_a_post(self.sharer)
+        self.post.shared_with.add(self.alice)
+        self.create_pre_authenticated_session("bud@test.io")
+        self.browser.get(self.live_server_url + f"/billboard/post/{self.post.id}/")
+
+    def test_duplicate_share_shows_error_brief_and_fyi_flashes_chip(self):
+        btn = self.wait_for(lambda: self.browser.find_element(By.ID, "id_bud_btn"))
+        btn.click()
+        recipient = self.wait_for(lambda: self.browser.find_element(By.ID, "id_recipient"))
+        recipient.send_keys("alice@test.io")
+        self.browser.find_element(By.CSS_SELECTOR, "#id_bud_panel .btn.btn-confirm").click()
+
+        title = self.wait_for(lambda: self.browser.find_element(
+            By.CSS_SELECTOR, ".note-banner--duplicate .note-banner__title"
+        ))
+        self.assertEqual(title.text, "@alice is already present")
+
+        # Existing chip carries data-user-id so the FYI highlight can find it
+        chip = self.browser.find_element(
+            By.CSS_SELECTOR, f".post-recipient[data-user-id='{self.alice.id}']"
+        )
+        self.assertNotIn("bud-duplicate-flash", chip.get_attribute("class") or "")
+
+        # FYI dismisses + applies flash class
+        self.browser.find_element(
+            By.CSS_SELECTOR, ".note-banner--duplicate .note-banner__fyi"
+        ).click()
+        self.wait_for(lambda: self.assertEqual(
+            self.browser.find_elements(By.CSS_SELECTOR, ".note-banner--duplicate"),
+            [],
+        ))
+        self.wait_for(lambda: self.assertIn(
+            "bud-duplicate-flash", chip.get_attribute("class") or ""
+        ))

src/functional_tests/test_gatekeeper_bud_btn.py

@@ -10,7 +10,7 @@ epic:invite_gamer w. Accept: application/json — server returns
 from selenium.webdriver.common.by import By
 
 from apps.billboard.models import Brief
-from apps.epic.models import Room, RoomInvite
+from apps.epic.models import GateSlot, Room, RoomInvite, TableSeat
 from apps.lyric.models import User
 
 from .base import FunctionalTest
@@ -114,3 +114,64 @@ class GatekeeperBudBtnAsyncInviteTest(FunctionalTest):
         self.wait_for(lambda: self.assertIn(
             self.alice, list(self.owner.buds.all())
         ))
+
+
+class GatekeeperBudBtnDuplicateInviteErrorTest(FunctionalTest):
+    """Re-inviting a recipient already seated in the room triggers the
+    error Brief titled `@<username> is already present`. FYI on the Brief
+    dismisses + adds .bud-duplicate-flash to the existing
+    .gate-slot.filled[data-user-id=…] element. Pending-but-unseated
+    duplicates also surface the Brief but FYI has no slot to highlight."""
+
+    def setUp(self):
+        super().setUp()
+        self.owner = User.objects.create(email="owner@test.io", username="owner")
+        self.alice = User.objects.create(email="alice@test.io", username="alice")
+        self.room = Room.objects.create(name="Dup Room", owner=self.owner)
+        # Seat alice via a GateSlot — _gate_positions renders .gate-slot.filled
+        # cells from GateSlot records (TableSeat spins up later at SIG SELECT),
+        # so the duplicate-highlight target lives there during gatekeeper phase.
+        GateSlot.objects.create(
+            room=self.room, gamer=self.alice, slot_number=1,
+            status=GateSlot.FILLED,
+        )
+        self.room_url = f"{self.live_server_url}/gameboard/room/{self.room.id}/gate/"
+        self.create_pre_authenticated_session("owner@test.io")
+        self.browser.get(self.room_url)
+
+    def test_duplicate_invite_shows_error_brief_and_fyi_flashes_slot(self):
+        btn = self.wait_for(lambda: self.browser.find_element(By.ID, "id_bud_btn"))
+        btn.click()
+        recipient = self.wait_for(lambda: self.browser.find_element(By.ID, "id_recipient"))
+        recipient.send_keys("alice@test.io")
+        self.browser.find_element(By.CSS_SELECTOR, "#id_bud_panel .btn.btn-confirm").click()
+
+        title = self.wait_for(lambda: self.browser.find_element(
+            By.CSS_SELECTOR, ".note-banner--duplicate .note-banner__title"
+        ))
+        self.assertEqual(title.text, "@alice is already present")
+
+        # No new RoomInvite or Brief persisted server-side on duplicate
+        self.assertFalse(RoomInvite.objects.filter(
+            room=self.room, invitee_email="alice@test.io",
+        ).exists())
+        self.assertEqual(
+            Brief.objects.filter(owner=self.owner, kind=Brief.KIND_GAME_INVITE).count(),
+            0,
+        )
+
+        slot = self.browser.find_element(
+            By.CSS_SELECTOR, f".gate-slot.filled[data-user-id='{self.alice.id}']"
+        )
+        self.assertNotIn("bud-duplicate-flash", slot.get_attribute("class") or "")
+
+        self.browser.find_element(
+            By.CSS_SELECTOR, ".note-banner--duplicate .note-banner__fyi"
+        ).click()
+        self.wait_for(lambda: self.assertEqual(
+            self.browser.find_elements(By.CSS_SELECTOR, ".note-banner--duplicate"),
+            [],
+        ))
+        self.wait_for(lambda: self.assertIn(
+            "bud-duplicate-flash", slot.get_attribute("class") or ""
+        ))

src/functional_tests/test_jasmine.py

@@ -1,3 +1,5 @@
+import re
+
 from selenium.webdriver.common.by import By
 from .base import FunctionalTest
 
@@ -8,7 +10,10 @@ class JasmineTest(FunctionalTest):
 
         def check_results():
             result = self.browser.find_element(By.CSS_SELECTOR, ".jasmine-overall-result")
-            if "0 failures" not in result.text:
+            # Word-boundary anchor — Jasmine 6 reports as "N specs, X failures".
+            # Plain `"0 failures" in text` matches "10 failures", "20 failures",
+            # etc., letting up to 99 failed specs slip past as green.
+            if not re.search(r"(?<!\d)0 failures\b", result.text):
                 failures = self.browser.find_elements(
                     By.CSS_SELECTOR, ".jasmine-failed .jasmine-description"
                 )

src/functional_tests/test_my_buds.py

@@ -88,3 +88,44 @@ class MyBudsPageTest(FunctionalTest):
         # No bud entries (the empty-state row has its own --empty class)
         entries = self.browser.find_elements(By.CSS_SELECTOR, ".bud-entry")
         self.assertEqual(len(entries), 0)
+
+    def test_re_add_existing_bud_shows_already_present_brief_and_fyi_flashes_bud_name(self):
+        """Re-adding an existing bud: server returns already_present=true;
+        client renders the error Brief titled `@alice is already present`;
+        clicking FYI dismisses the Brief AND adds .bud-duplicate-flash to
+        the existing .bud-name cell."""
+        self.gamer.buds.add(self.alice)
+        self.browser.get(self.live_server_url + "/billboard/my-buds/")
+        btn = self.wait_for(lambda: self.browser.find_element(By.ID, "id_bud_btn"))
+        btn.click()
+        recipient = self.wait_for(lambda: self.browser.find_element(By.ID, "id_recipient"))
+        recipient.send_keys("alice@test.io")
+        self.browser.find_element(By.CSS_SELECTOR, "#id_bud_panel .btn.btn-confirm").click()
+
+        # Error Brief appears w. the duplicate title
+        title = self.wait_for(lambda: self.browser.find_element(
+            By.CSS_SELECTOR, ".note-banner--duplicate .note-banner__title"
+        ))
+        self.assertEqual(title.text, "@alice is already present")
+
+        # Only one .bud-entry — no second alice row appended
+        self.assertEqual(
+            len(self.browser.find_elements(By.CSS_SELECTOR, ".bud-entry")),
+            1,
+        )
+
+        # Pre-flash: the .bud-name carries no flash class yet
+        bud_name = self.browser.find_element(
+            By.CSS_SELECTOR, f".bud-entry[data-bud-id='{self.alice.id}'] .bud-name"
+        )
+        self.assertNotIn("bud-duplicate-flash", bud_name.get_attribute("class") or "")
+
+        # Click FYI → Brief dismisses AND .bud-name gets the flash class
+        self.browser.find_element(By.CSS_SELECTOR, ".note-banner--duplicate .note-banner__fyi").click()
+        self.wait_for(lambda: self.assertEqual(
+            self.browser.find_elements(By.CSS_SELECTOR, ".note-banner--duplicate"),
+            [],
+        ))
+        self.wait_for(lambda: self.assertIn(
+            "bud-duplicate-flash", bud_name.get_attribute("class") or ""
+        ))

src/static/tests/NoteSpec.js

@@ -136,6 +136,123 @@ describe('Brief.showBanner', () => {
 
 });
 
+
+// ─────────────────────────────────────────────────────────────────────────────
+//
+// Brief.showDuplicateBanner — the "already added" error variant. Distinct
+// from showBanner because: the server doesn't persist a Brief row for these
+// (transient, client-only), title is rendered as `@<username> is already
+// present`, there's no date/square/post_url, and the FYI button toggles
+// `.bud-duplicate-flash` onto a caller-supplied target element instead of
+// navigating.
+//
+// API under test:
+//   Brief.showDuplicateBanner({ display_name, target_selector? })
+//     null / missing display_name → no banner
+//     target_selector matches an element → FYI click adds .bud-duplicate-flash
+//     target_selector missing or matches nothing → FYI just dismisses
+//
+// ─────────────────────────────────────────────────────────────────────────────
+
+describe('Brief.showDuplicateBanner', () => {
+
+    let fixture;
+
+    beforeEach(() => {
+        fixture = document.createElement('div');
+        fixture.id = 'dup-fixture';
+        fixture.innerHTML =
+            '<h2>Dash</h2>' +
+            '<ul id="bud-fixture-list">' +
+                '<li class="bud-entry" data-bud-id="42">' +
+                    '<span class="bud-name">alice</span>' +
+                '</li>' +
+            '</ul>';
+        document.body.appendChild(fixture);
+    });
+
+    afterEach(() => {
+        document.querySelectorAll('.note-banner').forEach(b => b.remove());
+        fixture.remove();
+    });
+
+    it('D1: missing display_name → no banner', () => {
+        Brief.showDuplicateBanner({});
+        expect(document.querySelector('.note-banner')).toBeNull();
+    });
+
+    it('D2: title reads "@<display_name> is already present"', () => {
+        Brief.showDuplicateBanner({ display_name: 'alice' });
+        const title = document.querySelector('.note-banner__title');
+        expect(title).not.toBeNull();
+        expect(title.textContent).toBe('@alice is already present');
+    });
+
+    it('D3: banner carries the .note-banner--duplicate modifier class', () => {
+        Brief.showDuplicateBanner({ display_name: 'alice' });
+        const b = document.querySelector('.note-banner');
+        expect(b).not.toBeNull();
+        expect(b.classList.contains('note-banner--duplicate')).toBeTrue();
+    });
+
+    it('D4: duplicate banner has no .note-banner__description or .note-banner__timestamp', () => {
+        Brief.showDuplicateBanner({ display_name: 'alice' });
+        expect(document.querySelector('.note-banner__description')).toBeNull();
+        expect(document.querySelector('.note-banner__timestamp')).toBeNull();
+    });
+
+    it('D5: FYI button is a <button>, not an <a> (no navigation)', () => {
+        Brief.showDuplicateBanner({ display_name: 'alice' });
+        const fyi = document.querySelector('.note-banner .note-banner__fyi');
+        expect(fyi).not.toBeNull();
+        expect(fyi.tagName.toLowerCase()).toBe('button');
+    });
+
+    it('D6: NVM dismisses without adding .bud-duplicate-flash anywhere', () => {
+        Brief.showDuplicateBanner({
+            display_name: 'alice',
+            target_selector: '.bud-entry[data-bud-id="42"] .bud-name',
+        });
+        document.querySelector('.note-banner__nvm').click();
+        expect(document.querySelector('.note-banner')).toBeNull();
+        const name = fixture.querySelector('.bud-name');
+        expect(name.classList.contains('bud-duplicate-flash')).toBeFalse();
+    });
+
+    it('D7: FYI dismisses AND adds .bud-duplicate-flash to the target element', () => {
+        Brief.showDuplicateBanner({
+            display_name: 'alice',
+            target_selector: '.bud-entry[data-bud-id="42"] .bud-name',
+        });
+        document.querySelector('.note-banner__fyi').click();
+        expect(document.querySelector('.note-banner')).toBeNull();
+        const name = fixture.querySelector('.bud-name');
+        expect(name.classList.contains('bud-duplicate-flash')).toBeTrue();
+    });
+
+    it('D8: FYI dismisses cleanly when target_selector is missing', () => {
+        Brief.showDuplicateBanner({ display_name: 'alice' });
+        document.querySelector('.note-banner__fyi').click();
+        expect(document.querySelector('.note-banner')).toBeNull();
+    });
+
+    it('D9: FYI dismisses cleanly when target_selector matches nothing', () => {
+        Brief.showDuplicateBanner({
+            display_name: 'alice',
+            target_selector: '.gate-slot[data-user-id="does-not-exist"]',
+        });
+        document.querySelector('.note-banner__fyi').click();
+        expect(document.querySelector('.note-banner')).toBeNull();
+    });
+
+    it('D10: title escapes HTML in display_name', () => {
+        Brief.showDuplicateBanner({ display_name: '<script>x</script>' });
+        const title = document.querySelector('.note-banner__title');
+        expect(title.textContent).toBe('@<script>x</script> is already present');
+        expect(title.querySelector('script')).toBeNull();
+    });
+});
+
 describe('Brief.handleSaveResponse', () => {
 
     afterEach(() => {

src/static_src/scss/_bud.scss

@@ -171,3 +171,17 @@ html:has(#id_kit_bag_dialog[open]) #id_bud_btn {
         outline: none;
     }
 }
+
+// ── Duplicate-add highlight ─────────────────────────────────────────────
+//
+// Eased-in flash applied by Brief.showDuplicateBanner's FYI button to a
+// caller-supplied target element — one of .bud-entry .bud-name (My Buds),
+// .post-recipient (post share), or .gate-slot.filled (gatekeeper invite).
+// Persists until page refresh; --terUser color + --ninUser text-shadow
+// per the duplicate-guard spec.
+
+.bud-duplicate-flash {
+    color: rgba(var(--terUser), 1);
+    text-shadow: 0 0 0.5em rgba(var(--ninUser), 1);
+    transition: color 600ms ease, text-shadow 600ms ease;
+}

src/static_src/tests/NoteSpec.js

@@ -136,6 +136,123 @@ describe('Brief.showBanner', () => {
 
 });
 
+
+// ─────────────────────────────────────────────────────────────────────────────
+//
+// Brief.showDuplicateBanner — the "already added" error variant. Distinct
+// from showBanner because: the server doesn't persist a Brief row for these
+// (transient, client-only), title is rendered as `@<username> is already
+// present`, there's no date/square/post_url, and the FYI button toggles
+// `.bud-duplicate-flash` onto a caller-supplied target element instead of
+// navigating.
+//
+// API under test:
+//   Brief.showDuplicateBanner({ display_name, target_selector? })
+//     null / missing display_name → no banner
+//     target_selector matches an element → FYI click adds .bud-duplicate-flash
+//     target_selector missing or matches nothing → FYI just dismisses
+//
+// ─────────────────────────────────────────────────────────────────────────────
+
+describe('Brief.showDuplicateBanner', () => {
+
+    let fixture;
+
+    beforeEach(() => {
+        fixture = document.createElement('div');
+        fixture.id = 'dup-fixture';
+        fixture.innerHTML =
+            '<h2>Dash</h2>' +
+            '<ul id="bud-fixture-list">' +
+                '<li class="bud-entry" data-bud-id="42">' +
+                    '<span class="bud-name">alice</span>' +
+                '</li>' +
+            '</ul>';
+        document.body.appendChild(fixture);
+    });
+
+    afterEach(() => {
+        document.querySelectorAll('.note-banner').forEach(b => b.remove());
+        fixture.remove();
+    });
+
+    it('D1: missing display_name → no banner', () => {
+        Brief.showDuplicateBanner({});
+        expect(document.querySelector('.note-banner')).toBeNull();
+    });
+
+    it('D2: title reads "@<display_name> is already present"', () => {
+        Brief.showDuplicateBanner({ display_name: 'alice' });
+        const title = document.querySelector('.note-banner__title');
+        expect(title).not.toBeNull();
+        expect(title.textContent).toBe('@alice is already present');
+    });
+
+    it('D3: banner carries the .note-banner--duplicate modifier class', () => {
+        Brief.showDuplicateBanner({ display_name: 'alice' });
+        const b = document.querySelector('.note-banner');
+        expect(b).not.toBeNull();
+        expect(b.classList.contains('note-banner--duplicate')).toBeTrue();
+    });
+
+    it('D4: duplicate banner has no .note-banner__description or .note-banner__timestamp', () => {
+        Brief.showDuplicateBanner({ display_name: 'alice' });
+        expect(document.querySelector('.note-banner__description')).toBeNull();
+        expect(document.querySelector('.note-banner__timestamp')).toBeNull();
+    });
+
+    it('D5: FYI button is a <button>, not an <a> (no navigation)', () => {
+        Brief.showDuplicateBanner({ display_name: 'alice' });
+        const fyi = document.querySelector('.note-banner .note-banner__fyi');
+        expect(fyi).not.toBeNull();
+        expect(fyi.tagName.toLowerCase()).toBe('button');
+    });
+
+    it('D6: NVM dismisses without adding .bud-duplicate-flash anywhere', () => {
+        Brief.showDuplicateBanner({
+            display_name: 'alice',
+            target_selector: '.bud-entry[data-bud-id="42"] .bud-name',
+        });
+        document.querySelector('.note-banner__nvm').click();
+        expect(document.querySelector('.note-banner')).toBeNull();
+        const name = fixture.querySelector('.bud-name');
+        expect(name.classList.contains('bud-duplicate-flash')).toBeFalse();
+    });
+
+    it('D7: FYI dismisses AND adds .bud-duplicate-flash to the target element', () => {
+        Brief.showDuplicateBanner({
+            display_name: 'alice',
+            target_selector: '.bud-entry[data-bud-id="42"] .bud-name',
+        });
+        document.querySelector('.note-banner__fyi').click();
+        expect(document.querySelector('.note-banner')).toBeNull();
+        const name = fixture.querySelector('.bud-name');
+        expect(name.classList.contains('bud-duplicate-flash')).toBeTrue();
+    });
+
+    it('D8: FYI dismisses cleanly when target_selector is missing', () => {
+        Brief.showDuplicateBanner({ display_name: 'alice' });
+        document.querySelector('.note-banner__fyi').click();
+        expect(document.querySelector('.note-banner')).toBeNull();
+    });
+
+    it('D9: FYI dismisses cleanly when target_selector matches nothing', () => {
+        Brief.showDuplicateBanner({
+            display_name: 'alice',
+            target_selector: '.gate-slot[data-user-id="does-not-exist"]',
+        });
+        document.querySelector('.note-banner__fyi').click();
+        expect(document.querySelector('.note-banner')).toBeNull();
+    });
+
+    it('D10: title escapes HTML in display_name', () => {
+        Brief.showDuplicateBanner({ display_name: '<script>x</script>' });
+        const title = document.querySelector('.note-banner__title');
+        expect(title.textContent).toBe('@<script>x</script> is already present');
+        expect(title.querySelector('script')).toBeNull();
+    });
+});
+
 describe('Brief.handleSaveResponse', () => {
 
     afterEach(() => {

src/templates/apps/billboard/_partials/_bud_add_panel.html

@@ -56,6 +56,9 @@
         onSuccess: function (data) {
             if (data.bud) _appendBudEntry(data.bud);
         },
+        duplicateTargetSelector: function (data) {
+            return '.bud-entry[data-bud-id="' + data.recipient_user_id + '"] .bud-name';
+        },
     });
 }());
 </script>

src/templates/apps/billboard/_partials/_bud_invite_panel.html

@@ -35,5 +35,12 @@ bindBudBtn({
     onSuccess: function (data) {
         if (window.Brief && data.brief) Brief.showBanner(data.brief);
     },
+    duplicateTargetSelector: function (data) {
+        // Pending RoomInvite duplicates have no recipient_user_id (no
+        // visible slot to highlight); selector returning null is fine —
+        // showDuplicateBanner's FYI just dismisses without easing.
+        if (!data.recipient_user_id) return null;
+        return '.gate-slot.filled[data-user-id="' + data.recipient_user_id + '"]';
+    },
 });
 </script>

src/templates/apps/billboard/_partials/_bud_panel.html

@@ -68,7 +68,9 @@
     // under .post-header. State transitions:
     //   0 → 1+ recipients : "just me, X" → "shared between {chip}" + "& me, X"
     //   ≥1 → +1 recipients: append chip + ", " separator before existing.
-    function _appendRecipientChip(displayName) {
+    // `userId` is stamped onto the chip as data-user-id so a later duplicate-
+    // share attempt can highlight this same element via .bud-duplicate-flash.
+    function _appendRecipientChip(displayName, userId) {
         if (!displayName) return;
         var header = document.querySelector('.post-page .post-header');
         if (!header) return;
@@ -78,6 +80,7 @@
         var chip = document.createElement('span');
         chip.className = 'post-recipient';
         chip.textContent = displayName;
+        if (userId) chip.dataset.userId = userId;
 
         if (existingRecipients) {
             existingRecipients.appendChild(document.createTextNode(', '));
@@ -103,7 +106,12 @@
         onSuccess: function (data) {
             if (data.line_text) _appendLine(data.line_text);
             if (window.Brief && data.brief) Brief.showBanner(data.brief);
-            if (data.recipient_display) _appendRecipientChip(data.recipient_display);
+            if (data.recipient_display) {
+                _appendRecipientChip(data.recipient_display, data.recipient_user_id);
+            }
+        },
+        duplicateTargetSelector: function (data) {
+            return '.post-recipient[data-user-id="' + data.recipient_user_id + '"]';
         },
     });
 }());

src/templates/apps/billboard/my_buds.html

@@ -1,4 +1,5 @@
 {% extends "core/base.html" %}
+{% load static %}
 {% load lyric_extras %}
 
 {% block title_text %}Billbuds{% endblock title_text %}
@@ -13,3 +14,9 @@
 {# Bud btn (bottom-left) + slide-out add-bud panel — async POST to add_bud. #}
 {% include "apps/billboard/_partials/_bud_add_panel.html" %}
 {% endblock content %}
+
+{% block scripts %}
+    {# Brief module — needed by _bud_add_panel's OK handler so the         #}
+    {# duplicate-add error banner can render via Brief.showDuplicateBanner.#}
+    <script src="{% static 'apps/dashboard/note.js' %}"></script>
+{% endblock scripts %}

src/templates/apps/billboard/post.html

@@ -18,7 +18,7 @@
             {# Owner viewing — owner-centric prose. "shared between" lists  #}
             {# every recipient; the self line is the owner's own handle.    #}
             {% if other_recipients %}
-                <p class="post-shared-recipients">shared between {% for r in other_recipients %}<span class="post-recipient post-attribution">{{ r|at_handle }}</span>{% if not forloop.last %}, {% endif %}{% endfor %}</p>
+                <p class="post-shared-recipients">shared between {% for r in other_recipients %}<span class="post-recipient post-attribution" data-user-id="{{ r.id }}">{{ r|at_handle }}</span>{% if not forloop.last %}, {% endif %}{% endfor %}</p>
                 <p class="post-shared-self">&amp; me, <span class="post-attribution">{{ post.owner|at_handle }} the {{ post.owner.active_title_display }}</span></p>
             {% else %}
                 <p class="post-shared-self">just me, <span class="post-attribution">{{ post.owner|at_handle }} the {{ post.owner.active_title_display }}</span></p>
@@ -28,7 +28,7 @@
             {# (request.user). Sole invitee collapses to a single line; the  #}
             {# "created by …" line attributes the post to its founder.      #}
             {% if other_recipients %}
-                <p class="post-shared-recipients">shared with {% for r in other_recipients %}<span class="post-recipient post-attribution">{{ r|at_handle }}</span>{% if not forloop.last %}, {% endif %}{% endfor %}</p>
+                <p class="post-shared-recipients">shared with {% for r in other_recipients %}<span class="post-recipient post-attribution" data-user-id="{{ r.id }}">{{ r|at_handle }}</span>{% if not forloop.last %}, {% endif %}{% endfor %}</p>
                 <p class="post-shared-self">&amp; me, <span class="post-attribution">{{ request.user|at_handle }} the {{ request.user.active_title_display }}</span></p>
             {% else %}
                 <p class="post-shared-self">shared with me, <span class="post-attribution">{{ request.user|at_handle }} the {{ request.user.active_title_display }}</span></p>

src/templates/apps/gameboard/_partials/_table_positions.html

@@ -1,7 +1,7 @@
 <div class="position-strip">
     {% for pos in gate_positions %}
         <div class="gate-slot{% if pos.slot.status == 'EMPTY' %} empty{% elif pos.slot.status == 'FILLED' %} filled{% elif pos.slot.status == 'RESERVED' %} reserved{% endif %}{% if pos.role_assigned %} role-assigned{% endif %}"
-             data-slot="{{ pos.slot.slot_number }}">
+             data-slot="{{ pos.slot.slot_number }}"{% if pos.slot.gamer %} data-user-id="{{ pos.slot.gamer.id }}"{% endif %}>
             <span class="slot-number">{{ pos.slot.slot_number }}</span>
             <span class="slot-gamer">{% if pos.slot.gamer %}{{ pos.slot.gamer.email }}{% else %}empty{% endif %}</span>
             {% if pos.slot.status == 'RESERVED' and pos.slot.gamer == request.user %}