From 5b9967b17d51c7485cf6bf5ca10a9807632fa721 Mon Sep 17 00:00:00 2001
From: DS Boyce <260543580+ds-boyce@users.noreply.github.com>
Date: Wed, 15 Jul 2026 09:23:11 -0700
Subject: [PATCH] Strip leading @ in from: queries (#11158)

---
 .../__tests__/search-posts-params.test.ts       | 17 +++++++++++++++++
 src/state/queries/search-posts-params.ts        | 15 +++++++++++++--
 2 files changed, 30 insertions(+), 2 deletions(-)

diff --git a/src/state/queries/__tests__/search-posts-params.test.ts b/src/state/queries/__tests__/search-posts-params.test.ts
index 9436507cc2..9b0c374642 100644
--- a/src/state/queries/__tests__/search-posts-params.test.ts
+++ b/src/state/queries/__tests__/search-posts-params.test.ts
@@ -26,6 +26,23 @@ describe(`extractSearchPostsParams`, () => {
       input: `cats to:alice`,
       output: {q: `cats`, mentions: `alice`},
     },
+    // Handles may be typed with a leading @ (e.g. from:@alice.bsky.social),
+    // which the appview rejects. Strip it to match the advanced-search dialog.
+    {
+      name: `strips a leading @ from from:`,
+      input: `cats from:@alice.bsky.social`,
+      output: {q: `cats`, author: `alice.bsky.social`},
+    },
+    {
+      name: `strips a leading @ from mentions:`,
+      input: `cats mentions:@alice.bsky.social`,
+      output: {q: `cats`, mentions: `alice.bsky.social`},
+    },
+    {
+      name: `strips a leading @ from to: (mentions alias)`,
+      input: `cats to:@alice.bsky.social`,
+      output: {q: `cats`, mentions: `alice.bsky.social`},
+    },
     // `me` is resolved by the backend, so the :me operators stay in q verbatim
     // instead of being lifted into author/mentions.
     {
diff --git a/src/state/queries/search-posts-params.ts b/src/state/queries/search-posts-params.ts
index 70dfe728ba..dcfd9aa4b5 100644
--- a/src/state/queries/search-posts-params.ts
+++ b/src/state/queries/search-posts-params.ts
@@ -13,6 +13,17 @@ import {
 
 const DATE_RE = /^\d{4}-\d{2}-\d{2}/
 
+/**
+ * Strips a leading `@` from a handle so `from:@alice.bsky.social` and
+ * `from:alice.bsky.social` both resolve to the same author. Mirrors the marker
+ * stripping the advanced-search dialog applies to handles entered in its
+ * filter fields (see `serializeAdvancedSearch`), which otherwise 400s the
+ * appview.
+ */
+function stripHandleMarker(value: string): string {
+  return value.startsWith('@') ? value.slice(1) : value
+}
+
 export type ExtractedSearchParams = {
   q: string
   author?: string
@@ -111,12 +122,12 @@ export function extractSearchPostsParams(query: string): ExtractedSearchParams {
          * query text verbatim rather than lifting it into a structured param.
          */
         if (value === 'me') remaining.push(token)
-        else result.author ??= value
+        else result.author ??= stripHandleMarker(value)
         break
       case 'mentions':
       case 'to':
         if (value === 'me') remaining.push(token)
-        else result.mentions ??= value
+        else result.mentions ??= stripHandleMarker(value)
         break
       case 'domain':
         result.domain ??= value