v2.3.2: group hosts by certificate fingerprint

1 files changed, 26 insertions, 2 deletions

diff --git a/src/client/ui.rs b/src/client/ui.rs
index 1a35db1..0fe78ae 100644
--- a/src/client/ui.rs
+++ b/src/client/ui.rs
@@ -247,14 +247,38 @@ pub fn first_contact_lines(addr: &str, fingerprint: &str) -> Vec<String> {
 
 /// Format remembered hosts so a 64-character fingerprint does not wrap on an
 /// 80-column terminal.
+/// Render remembered hosts.
+///
+/// Two addresses that present the same certificate key are the same server, so
+/// they are grouped under one fingerprint: `127.0.0.1:11525` and
+/// `10.0.0.100:11525` reached through different networks still show as one
+/// entry. Hosts without a fingerprint are never merged, since nothing proves
+/// they are related.
 pub fn host_lines(hosts: &[(String, Option<String>)]) -> Vec<String> {
     if hosts.is_empty() {
         return vec!["No remembered hosts.".to_string()];
     }
 
-    let mut lines = vec!["Remembered hosts:".to_string()];
+    let mut groups: Vec<(Option<&str>, Vec<&str>)> = Vec::new();
     for (host, fingerprint) in hosts {
-        lines.push(format!("  {host}"));
+        match fingerprint {
+            Some(fingerprint) => {
+                match groups
+                    .iter_mut()
+                    .find(|(key, _)| *key == Some(fingerprint.as_str()))
+                {
+                    Some((_, addresses)) => addresses.push(host),
+                    None => groups.push((Some(fingerprint), vec![host])),
+                }
+            }
+            // An unknown key proves nothing about identity.
+            None => groups.push((None, vec![host])),
+        }
+    }
+
+    let mut lines = vec!["Remembered hosts:".to_string()];
+    for (fingerprint, addresses) in groups {
+        lines.push(format!("  {}", addresses.join(", ")));
         match fingerprint {
             Some(fingerprint) => lines.push(format!("  fingerprint: {fingerprint}")),
             None => lines.push("  (no fingerprint)".to_string()),