fix: percent-encode identifier in nostr:// URLs and GRASP HTTP paths

Repository identifiers can contain any characters per NIP-01 d-tag rules.
Encode them in nostr:// clone URLs (display and parse) and in GRASP
/<npub>/<identifier>.git paths, aligning with NIP-34 and GRASP-01.

3 files changed, 63 insertions, 8 deletions

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 8594feb..bd3c4dc 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -15,6 +15,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 - more robust patch parsing and gracefully handle errors (7a36aed, e1dd109, 6a2245d),
 - panic when cloning a bare `nostr://npub/identifier` URL with no relay hints (f3a6ae8)
+- repository identifiers containing reserved characters (e.g. spaces, emoji) are now percent-encoded in `nostr://` clone URLs and GRASP HTTP paths, per [NIP-34](https://github.com/nostr-protocol/nips/pull/2312)
 
 ## [2.3.0] - 2026-03-05
 
diff --git a/src/lib/git/nostr_url.rs b/src/lib/git/nostr_url.rs
index c26c56a..d6ee24e 100644
--- a/src/lib/git/nostr_url.rs
+++ b/src/lib/git/nostr_url.rs
@@ -95,7 +95,7 @@ impl fmt::Display for NostrUrlDecoded {
                 )
             )?;
         }
-        write!(f, "{}", self.coordinate.identifier)
+        write!(f, "{}", urlencoding::encode(&self.coordinate.identifier))
     }
 }
 
@@ -178,10 +178,11 @@ impl NostrUrlDecoded {
         } else {
             let npub_or_nip05 = part.to_owned();
             parts.remove(0);
-            let identifier = parts
-                .pop()
-                .context("nostr url must have an identifier eg. nostr://npub123/repo-identifier")?
-                .to_string();
+            let identifier = urlencoding::decode(parts.pop().context(
+                "nostr url must have an identifier eg. nostr://npub123/repo-identifier",
+            )?)
+            .context("could not percent-decode identifier in nostr git url")?
+            .into_owned();
             for relay in parts {
                 let mut decoded = urlencoding::decode(relay)
                     .context("could not parse relays in nostr git url")?
@@ -1058,6 +1059,31 @@ mod tests {
         }
 
         #[test]
+        fn identifier_with_spaces_is_percent_encoded() -> Result<()> {
+            assert_eq!(
+                format!("{}", NostrUrlDecoded {
+                    original_string: String::new(),
+                    coordinate: Nip19Coordinate {
+                        coordinate: Coordinate {
+                            identifier: "my repo".to_string(),
+                            public_key: PublicKey::parse(
+                                "npub15qydau2hjma6ngxkl2cyar74wzyjshvl65za5k5rl69264ar2exs5cyejr",
+                            )
+                            .unwrap(),
+                            kind: nostr_sdk::Kind::GitRepoAnnouncement,
+                        },
+                        relays: vec![],
+                    },
+                    protocol: None,
+                    ssh_key_file: None,
+                    nip05: None,
+                }),
+                "nostr://npub15qydau2hjma6ngxkl2cyar74wzyjshvl65za5k5rl69264ar2exs5cyejr/my%20repo",
+            );
+            Ok(())
+        }
+
+        #[test]
         fn with_protocol() -> Result<()> {
             assert_eq!(
                 format!("{}", NostrUrlDecoded {
@@ -1353,6 +1379,32 @@ mod tests {
                 }
 
                 #[tokio::test]
+                async fn percent_encoded_identifier_is_decoded() -> Result<()> {
+                    let url = "nostr://npub15qydau2hjma6ngxkl2cyar74wzyjshvl65za5k5rl69264ar2exs5cyejr/my%20repo".to_string();
+                    let decoded = NostrUrlDecoded::parse_and_resolve(&url, &None).await?;
+                    assert_eq!(decoded.coordinate.identifier, "my repo");
+                    Ok(())
+                }
+
+                #[tokio::test]
+                async fn percent_encoded_identifier_round_trips() -> Result<()> {
+                    // parse a URL with an encoded identifier, then re-display it and get the same
+                    // URL back
+                    let url = "nostr://npub15qydau2hjma6ngxkl2cyar74wzyjshvl65za5k5rl69264ar2exs5cyejr/my%20repo".to_string();
+                    let decoded = NostrUrlDecoded::parse_and_resolve(&url, &None).await?;
+                    // Display re-encodes, but original_string is stored so we need a fresh struct
+                    let redisplayed = format!(
+                        "{}",
+                        NostrUrlDecoded {
+                            original_string: String::new(),
+                            ..decoded
+                        }
+                    );
+                    assert_eq!(redisplayed, url);
+                    Ok(())
+                }
+
+                #[tokio::test]
                 async fn with_server_protocol() -> Result<()> {
                     let url = "nostr://ssh/npub15qydau2hjma6ngxkl2cyar74wzyjshvl65za5k5rl69264ar2exs5cyejr/ngit".to_string();
                     assert_eq!(
diff --git a/src/lib/repo_ref.rs b/src/lib/repo_ref.rs
index c0f9136..c4dd820 100644
--- a/src/lib/repo_ref.rs
+++ b/src/lib/repo_ref.rs
@@ -14,6 +14,7 @@ use nostr::{
 };
 use nostr_sdk::{Kind, NostrSigner, RelayUrl, Timestamp, Url};
 use serde::{Deserialize, Serialize};
+use urlencoding::encode as pct_encode;
 
 #[cfg(not(test))]
 use crate::client::Client;
@@ -661,7 +662,7 @@ pub fn detect_existing_grasp_servers(
         }
 
         let clone_url_is_grasp_server_format = if let Ok(npub) = extract_npub(url) {
-            url.contains(&format!("/{npub}/{identifier}.git"))
+            url.contains(&format!("/{npub}/{}.git", pct_encode(identifier)))
         } else {
             false
         };
@@ -809,8 +810,9 @@ pub fn format_grasp_server_url_as_clone_url(
         "https://"
     };
     Ok(format!(
-        "{prefix}{grasp_server_url}/{}/{identifier}.git",
-        public_key.to_bech32()?
+        "{prefix}{grasp_server_url}/{}/{}.git",
+        public_key.to_bech32()?,
+        pct_encode(identifier)
     ))
 }