huskies: merge 606_story_extract_project_service

server/src/service/project/selection.rs

@@ -0,0 +1,100 @@
+//! Pure project-selection logic — no I/O, no async, no side effects.
+//!
+//! All functions here are deterministic and depend only on their arguments.
+
+/// Promote a project path to the front of the known-projects list.
+///
+/// Removes any existing occurrence of `path` and inserts it at position 0,
+/// so the most-recently-opened project is always first.
+pub fn promote_to_front(mut projects: Vec<String>, path: &str) -> Vec<String> {
+    projects.retain(|p| p != path);
+    projects.insert(0, path.to_string());
+    projects
+}
+
+#[allow(dead_code)]
+/// Extract the display name for a project from its filesystem path.
+///
+/// Returns the last non-empty path component, or `None` for root or empty input.
+pub fn project_name_from_path(path: &str) -> Option<&str> {
+    path.trim_end_matches('/')
+        .rsplit('/')
+        .find(|s| !s.is_empty())
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn promote_to_front_inserts_new_path_at_position_zero() {
+        let result = promote_to_front(vec!["/a".to_string(), "/b".to_string()], "/c");
+        assert_eq!(result, vec!["/c", "/a", "/b"]);
+    }
+
+    #[test]
+    fn promote_to_front_moves_existing_entry_to_front() {
+        let result = promote_to_front(
+            vec!["/a".to_string(), "/b".to_string(), "/c".to_string()],
+            "/b",
+        );
+        assert_eq!(result, vec!["/b", "/a", "/c"]);
+    }
+
+    #[test]
+    fn promote_to_front_is_idempotent_when_already_first() {
+        let result = promote_to_front(vec!["/a".to_string(), "/b".to_string()], "/a");
+        assert_eq!(result, vec!["/a", "/b"]);
+    }
+
+    #[test]
+    fn promote_to_front_handles_empty_list() {
+        let result = promote_to_front(vec![], "/new");
+        assert_eq!(result, vec!["/new"]);
+    }
+
+    #[test]
+    fn promote_to_front_deduplicates_single_entry() {
+        let result = promote_to_front(vec!["/a".to_string()], "/a");
+        assert_eq!(result, vec!["/a"]);
+    }
+
+    #[test]
+    fn project_name_from_path_extracts_last_component() {
+        assert_eq!(
+            project_name_from_path("/home/user/myproject"),
+            Some("myproject")
+        );
+    }
+
+    #[test]
+    fn project_name_from_path_handles_trailing_slash() {
+        assert_eq!(
+            project_name_from_path("/home/user/myproject/"),
+            Some("myproject")
+        );
+    }
+
+    #[test]
+    fn project_name_from_path_returns_none_for_root() {
+        assert_eq!(project_name_from_path("/"), None);
+    }
+
+    #[test]
+    fn project_name_from_path_returns_none_for_empty() {
+        assert_eq!(project_name_from_path(""), None);
+    }
+
+    #[test]
+    fn project_name_from_path_handles_single_component() {
+        assert_eq!(project_name_from_path("myproject"), Some("myproject"));
+    }
+
+    #[test]
+    fn project_name_from_path_handles_deep_path() {
+        assert_eq!(
+            project_name_from_path("/a/b/c/d/project-name"),
+            Some("project-name")
+        );
+    }
+}