chore: remove unnecessary optimization (#20)

Reviewed-on: #20

crates/workspace/src/views/status_list.rs

@@ -0,0 +1,45 @@
+use nostr::prelude::Event;
+use signed_core::RepoStatus;
+
+/// Root events counted by their resolved status.
+#[derive(Clone, Copy, Debug, Default, PartialEq, Eq)]
+pub(crate) struct StatusCounts {
+    pub(crate) total: usize,
+    pub(crate) open: usize,
+    pub(crate) closed: usize,
+    pub(crate) draft: usize,
+    pub(crate) applied: usize,
+}
+
+impl StatusCounts {
+    fn record(&mut self, status: RepoStatus) {
+        self.total += 1;
+        match status {
+            RepoStatus::Open => self.open += 1,
+            RepoStatus::Closed => self.closed += 1,
+            RepoStatus::Draft => self.draft += 1,
+            RepoStatus::Applied => self.applied += 1,
+        }
+    }
+}
+
+/// Indices of `roots` whose status `keep` accepts, counting every root's status.
+pub(crate) fn filter_by_status<'a>(
+    roots: impl IntoIterator<Item = &'a Event>,
+    status_of: impl Fn(&Event) -> RepoStatus,
+    keep: impl Fn(RepoStatus) -> bool,
+) -> (Vec<usize>, StatusCounts) {
+    let mut counts = StatusCounts::default();
+
+    let visible = roots
+        .into_iter()
+        .enumerate()
+        .filter_map(|(index, root)| {
+            let status = status_of(root);
+            counts.record(status);
+            keep(status).then_some(index)
+        })
+        .collect();
+
+    (visible, counts)
+}