Batch r2-1 review: a report reason blank after cleaning is refused

apps/figcraft-server/src/store.rs

@@ -296,7 +296,8 @@ fn clean_name(s: &str) -> String {
 
 /// A report's reason: trimmed, control and bidi characters turned into spaces, at most `MAX_REASON` characters.
 fn clean_reason(s: &str) -> String {
-    s.trim().chars().map(|c| if c.is_control() || is_bidi_control(c) { ' ' } else { c }).take(MAX_REASON).collect()
+    let s: String = s.chars().map(|c| if c.is_control() || is_bidi_control(c) { ' ' } else { c }).collect();
+    s.trim().chars().take(MAX_REASON).collect()
 }
 
 /// Bidirectional format characters, which could reorder what a terminal shows.

apps/figcraft-server/src/store_tests.rs

@@ -391,6 +391,11 @@ fn names_and_report_reasons_lose_bidi_controls() {
         assert_eq!(store.reports().last().unwrap().reason, "a b", "reason U+{:04X}", m as u32);
         store.remove(&id).unwrap();
     }
+    // A reason that is only control characters says nothing.
+    let (id, _, _) = publish(&mut store, "blank");
+    for blank in ["\0", "\u{202E}", " \0\t\u{2066} "] {
+        assert!(store.keep_report(&id, None, "192.0.2.99".parse().unwrap(), blank).is_err(), "{blank:?}");
+    }
 }
 
 #[test]