git: refresh index stat cache after CLI status

userland/git/src/changes.rs

@@ -1,4 +1,4 @@
-//! Read-only snapshots and patches. Ordinary Git state only; never refresh/write the index.
+//! Snapshots and patches. Only CLI status refreshes the ordinary Git index stat cache.
 use crate::Result;
 use crate::{
     HeadInfo, head_info,
@@ -223,6 +223,13 @@ fn changes(old: &Snapshot, new: &Snapshot) -> Vec<Change> {
         .collect()
 }
 pub fn status(repo: &gix::Repository) -> Result<Status> {
+    status_inner(repo, false)
+}
+/// CLI status refreshes cached file stats. RPC status remains read-only.
+pub fn refresh_status(repo: &gix::Repository) -> Result<Status> {
+    status_inner(repo, true)
+}
+fn status_inner(repo: &gix::Repository, refresh: bool) -> Result<Status> {
     repo::worktree(repo)?;
     let (index, conflicts) = index(repo)?;
     let mut head = tree(repo, "HEAD")?;
@@ -237,13 +244,13 @@ pub fn status(repo: &gix::Repository) -> Result<Status> {
         conflicted: conflicts.iter().map(|p| display(p)).collect(),
     };
     use gix::status::index_worktree::{Item, iter::Summary};
-    let iter = repo
+    let mut iter = repo
         .status(gix::progress::Discard)
         .map_err(|e| error("status", e))?
         .untracked_files(gix::status::UntrackedFiles::Files)
         .into_index_worktree_iter(Vec::<gix::bstr::BString>::new())
         .map_err(|e| error("status", e))?;
-    for item in iter {
+    for item in iter.by_ref() {
         let item = item.map_err(|e| error("status", e))?;
         #[cfg(target_os = "wasi")]
         if matches!(
@@ -285,6 +292,13 @@ pub fn status(repo: &gix::Repository) -> Result<Status> {
             },
         });
     }
+    if refresh
+        && let Some(mut outcome) = iter.into_outcome()
+        && outcome.has_changes()
+    {
+        // A read-only repository must still support status, like native Git.
+        let _ = outcome.write_changes();
+    }
     result.unstaged.sort_by(|a, b| a.path.cmp(&b.path));
     result.untracked.sort();
     Ok(result)

userland/git/src/lib.rs

@@ -808,7 +808,7 @@ pub fn run(cli: Cli) -> Result<i32> {
             porcelain,
             branch,
         } => {
-            let mut status = changes::status(&repository)?;
+            let mut status = changes::refresh_status(&repository)?;
             let index = repository
                 .index_or_empty()
                 .map_err(|e| error("status index", e))?;