fix(channels): strip leading hash prefixes from names (#2250)

Signed-off-by: Logan Johnson <loganj@squareup.com>
Signed-off-by: npub1z3hmzc9ryehxzedl5wzlvpyvja0d483peaja5zt6pd0209f9x2jspe2dxh <146fb160a3266e6165bfa385f6048c975eda9e21cf65da097a0b5ea7952532a5@buzz.block.builderlab.xyz>
Signed-off-by: npub13n66s06epmqf2kc3v373ez8hj65cuzyvxzjf93vwpervxqn2u7jq2qd9je <8cf5a83f590ec0955b11647d1c88f796a98e088c30a492c58e0e46c3026ae7a4@buzz.block.builderlab.xyz>
Co-authored-by: npub1z3hmzc9ryehxzedl5wzlvpyvja0d483peaja5zt6pd0209f9x2jspe2dxh <146fb160a3266e6165bfa385f6048c975eda9e21cf65da097a0b5ea7952532a5@buzz.block.builderlab.xyz>
Co-authored-by: npub13n66s06epmqf2kc3v373ez8hj65cuzyvxzjf93vwpervxqn2u7jq2qd9je <8cf5a83f590ec0955b11647d1c88f796a98e088c30a492c58e0e46c3026ae7a4@buzz.block.builderlab.xyz>

desktop/src-tauri/src/events.rs

@@ -148,6 +148,10 @@ pub fn build_create_channel(
     about: Option<&str>,
     ttl_seconds: Option<i32>,
 ) -> Result<EventBuilder, String> {
+    let name = buzz_sdk_pkg::canonical_channel_name(name);
+    if name.trim().is_empty() {
+        return Err("channel name is required".into());
+    }
     let mut tags = vec![
         tag(vec!["h", &channel_id.to_string()])?,
         tag(vec!["name", name])?,
@@ -194,6 +198,10 @@ pub fn build_update_channel(
             return Err("visibility must be \"open\" or \"private\"".into());
         }
     }
+    let name = name.map(buzz_sdk_pkg::canonical_channel_name);
+    if name.is_some_and(|name| name.trim().is_empty()) {
+        return Err("channel name is required".into());
+    }
     let mut tags = vec![tag(vec!["h", &channel_id.to_string()])?];
     if let Some(n) = name {
         tags.push(tag(vec!["name", n])?);
@@ -842,7 +850,12 @@ pub fn build_approval_deny(token: &str, note: Option<&str>) -> Result<EventBuild
 mod tests {
     use super::*;
     use nostr::Keys;
-
+    #[test]
+    fn channel_builders_reject_hash_only_names() {
+        let channel_id = Uuid::new_v4();
+        assert!(build_create_channel(channel_id, "###", "open", "stream", None, None).is_err());
+        assert!(build_update_channel(channel_id, Some("###"), None, None, None).is_err());
+    }
     /// Builder layout regression for the NIP-IA owner-of-agent archive flow.
     /// Compares against `docs/nips/NIP-IA.md` §Vector 1.
     #[test]

desktop/src/features/channels/lib/canonicalChannelName.test.mjs

@@ -0,0 +1,22 @@
+import assert from "node:assert/strict";
+import test from "node:test";
+
+import {
+  canonicalChannelName,
+  channelNamesMatch,
+} from "./canonicalChannelName.ts";
+
+test("canonicalChannelName strips interleaved leading hashes and whitespace", () => {
+  assert.equal(canonicalChannelName("channel"), "channel");
+  assert.equal(canonicalChannelName("#channel"), "channel");
+  assert.equal(canonicalChannelName("  ### channel  "), "channel");
+  assert.equal(canonicalChannelName("# #"), "");
+  assert.equal(canonicalChannelName("### ###"), "");
+  assert.equal(canonicalChannelName("channel#topic"), "channel#topic");
+});
+
+test("channelNamesMatch canonicalizes both legacy names and search input", () => {
+  assert.equal(channelNamesMatch("#general", "general"), true);
+  assert.equal(channelNamesMatch("general", " #GENERAL "), true);
+  assert.equal(channelNamesMatch("#random", "general"), false);
+});

desktop/src/features/channels/lib/canonicalChannelName.ts

@@ -0,0 +1,14 @@
+/**
+ * Returns the stored form of a channel name after removing the display prefix.
+ * Keep this aligned with `buzz_core::channel::canonical_channel_name`.
+ */
+export function canonicalChannelName(name: string): string {
+  return name.replace(/^[#\s]+/u, "").trimEnd();
+}
+
+export function channelNamesMatch(left: string, right: string): boolean {
+  return (
+    canonicalChannelName(left).toLowerCase() ===
+    canonicalChannelName(right).toLowerCase()
+  );
+}

desktop/src/features/channels/ui/ChannelBrowserDialog.tsx

@@ -9,6 +9,10 @@ import {
 } from "lucide-react";
 
 import type { Channel } from "@/shared/api/types";
+import {
+  canonicalChannelName,
+  channelNamesMatch,
+} from "@/features/channels/lib/canonicalChannelName";
 import { scoreChannelMatch } from "@/features/channels/lib/channelSearchScore";
 import {
   type ChannelSortMode,
@@ -127,8 +131,9 @@ export function ChannelBrowserDialog({
     left: 0,
     width: 0,
   });
-  const deferredQuery = React.useDeferredValue(query.trim().toLowerCase());
-  const trimmedQuery = query.trim();
+  const canonicalQuery = canonicalChannelName(query);
+  const deferredQuery = React.useDeferredValue(canonicalQuery.toLowerCase());
+  const trimmedQuery = canonicalQuery;
   // Immediate (non-deferred) lowercased query. The create row's visibility
   // (via hasExactMatch) and its label both read from the live query so they
   // can never disagree for a frame while the fuzzy filter catches up.
@@ -244,7 +249,7 @@ export function ChannelBrowserDialog({
       channels.some(
         (channel) =>
           channel.channelType !== "dm" &&
-          channel.name.toLowerCase() === normalizedQuery &&
+          channelNamesMatch(channel.name, normalizedQuery) &&
           (channelTypeFilter
             ? channel.channelType === channelTypeFilter
             : true),