feat: out-of-box experience (#2)

Reviewed-on: https://git.reya.su/reya/signed/pulls/2

crates/signed_core/src/status.rs

@@ -30,13 +30,15 @@ impl RepoStatus {
     }
 }
 
-/// Check whether a status event references the given root event via an `e` tag.
+/// Check whether an event references the given root event via an `e` or `E`
+/// tag. NIP-10 / NIP-34 use the lowercase `e` tag; NIP-22 comments (kind
+/// `1111`) use the uppercase `E` tag for the root of the thread.
 pub fn references_root(event: &Event, root: &EventId) -> bool {
-    let root_hex: String = root.to_hex();
+    let root = root.to_hex();
     event
         .tags
         .iter()
-        .any(|t| t.kind() == "e" && t.content() == Some(root_hex.as_str()))
+        .any(|tag| matches!(tag.kind(), "e" | "E") && tag.content() == Some(root.as_str()))
 }
 
 /// Resolve the status of a root event per NIP-34:
@@ -58,3 +60,154 @@ where
         .and_then(|e| RepoStatus::from_kind(e.kind))
         .unwrap_or(RepoStatus::Open)
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    const ROOT_ID_HEX: &str = "1111111111111111111111111111111111111111111111111111111111111111";
+    const OTHER_ID_HEX: &str = "2222222222222222222222222222222222222222222222222222222222222222";
+
+    fn keys_from_hex(hex: &str) -> Keys {
+        Keys::new(SecretKey::from_hex(hex).expect("valid secret key"))
+    }
+
+    fn root_event_id() -> EventId {
+        EventId::from_hex(ROOT_ID_HEX).expect("valid event id")
+    }
+
+    /// Build a signed status event with a controlled `created_at`.
+    fn status_event(author: &Keys, kind: Kind, root: EventId, created_at: u64) -> Event {
+        EventBuilder::new(kind, "")
+            .tags([Tag::event(root)])
+            .custom_created_at(Timestamp::from(created_at))
+            .finalize(author)
+            .expect("signed event")
+    }
+
+    #[test]
+    fn references_root_matches_e_tag() {
+        let root = root_event_id();
+        let event = EventBuilder::new(Kind::GitStatusOpen, "")
+            .tags([Tag::event(root)])
+            .finalize(&keys_from_hex(
+                "0000000000000000000000000000000000000000000000000000000000000001",
+            ))
+            .expect("signed event");
+
+        assert!(references_root(&event, &root));
+        assert!(!references_root(
+            &event,
+            &EventId::from_hex(OTHER_ID_HEX).expect("valid id")
+        ));
+    }
+
+    #[test]
+    fn references_root_matches_uppercase_e_tag() {
+        let root = root_event_id();
+        let event = EventBuilder::new(Kind::Comment, "")
+            .tags([Tag::parse(["E", ROOT_ID_HEX]).expect("valid E tag")])
+            .finalize(&keys_from_hex(
+                "0000000000000000000000000000000000000000000000000000000000000001",
+            ))
+            .expect("signed event");
+
+        assert!(references_root(&event, &root));
+        assert!(!references_root(
+            &event,
+            &EventId::from_hex(OTHER_ID_HEX).expect("valid id")
+        ));
+    }
+
+    #[test]
+    fn references_root_false_without_e_tags() {
+        let event = EventBuilder::new(Kind::GitStatusOpen, "")
+            .finalize(&keys_from_hex(
+                "0000000000000000000000000000000000000000000000000000000000000001",
+            ))
+            .expect("signed event");
+
+        assert!(!references_root(&event, &root_event_id()));
+    }
+
+    #[test]
+    fn defaults_to_open_without_status_events() {
+        let owner =
+            keys_from_hex("0000000000000000000000000000000000000000000000000000000000000001");
+        let maintainer =
+            keys_from_hex("0000000000000000000000000000000000000000000000000000000000000002");
+
+        let statuses: Vec<Event> = Vec::new();
+
+        assert_eq!(
+            resolve_status(
+                statuses.iter(),
+                &owner.public_key(),
+                &[maintainer.public_key()]
+            ),
+            RepoStatus::Open
+        );
+    }
+
+    #[test]
+    fn latest_status_wins() {
+        let owner =
+            keys_from_hex("0000000000000000000000000000000000000000000000000000000000000001");
+        let maintainer =
+            keys_from_hex("0000000000000000000000000000000000000000000000000000000000000002");
+        let root = root_event_id();
+
+        let statuses = [
+            status_event(&maintainer, Kind::GitStatusClosed, root, 100),
+            status_event(&owner, Kind::GitStatusOpen, root, 200),
+        ];
+
+        assert_eq!(
+            resolve_status(
+                statuses.iter(),
+                &owner.public_key(),
+                &[maintainer.public_key()]
+            ),
+            RepoStatus::Open
+        );
+    }
+
+    #[test]
+    fn ignores_statuses_from_others() {
+        let owner =
+            keys_from_hex("0000000000000000000000000000000000000000000000000000000000000001");
+        let maintainer =
+            keys_from_hex("0000000000000000000000000000000000000000000000000000000000000002");
+        let stranger =
+            keys_from_hex("0000000000000000000000000000000000000000000000000000000000000003");
+        let root = root_event_id();
+
+        let statuses = [
+            status_event(&stranger, Kind::GitStatusClosed, root, 300),
+            status_event(&maintainer, Kind::GitStatusDraft, root, 100),
+        ];
+
+        assert_eq!(
+            resolve_status(
+                statuses.iter(),
+                &owner.public_key(),
+                &[maintainer.public_key()]
+            ),
+            RepoStatus::Draft
+        );
+    }
+
+    #[test]
+    fn ignores_non_status_kinds() {
+        let owner =
+            keys_from_hex("0000000000000000000000000000000000000000000000000000000000000001");
+        let root = root_event_id();
+
+        let statuses = [status_event(&owner, Kind::GitIssue, root, 100)];
+
+        assert_eq!(
+            resolve_status(statuses.iter(), &owner.public_key(), &[]),
+            RepoStatus::Open
+        );
+    }
+}