Merge nucleic/zesty-ancient-koala-i9if into dev

nash-observe/src/lib.rs

@@ -398,6 +398,30 @@ fn read_back(record: &brush_core::gate::RedirectRecord) -> Option<(u64, Vec<u8>,
     Some((total, buf, total > n as u64))
 }
 
+/// Resolve a redirection target against the directory its command ran in, so the
+/// reported path is meaningful to a host that never saw that cwd. Purely lexical
+/// (`.`/`..` collapsed, no symlink resolution, no filesystem access): the target of a
+/// truncating write may not exist yet, and observation must never stat its way into a
+/// slow or hanging path.
+fn absolute_path(path: &Path, cwd: &Path) -> PathBuf {
+    let joined = if path.is_absolute() {
+        path.to_path_buf()
+    } else {
+        cwd.join(path)
+    };
+    let mut out = PathBuf::new();
+    for component in joined.components() {
+        match component {
+            std::path::Component::CurDir => {}
+            std::path::Component::ParentDir => {
+                out.pop();
+            }
+            other => out.push(other.as_os_str()),
+        }
+    }
+    out
+}
+
 /// Build a preview string (redacted, base64) from captured bytes. Binary data is
 /// previewed as a hex head rather than mangled UTF-8.
 fn preview_b64(data: &[u8]) -> String {
@@ -502,6 +526,14 @@ impl brush_core::gate::Gate for RecordingGate {
 
             // Data-flow read-back for this command's redirects (docs/NASH.md §5.2).
             for record in &pending.redirects {
+                // The host resolves a redirect target against the session's worktree to decide
+                // which file was edited (and which lock that is), so report the path absolutely:
+                // `> out.txt` is only meaningful next to the directory the command ran in, and the
+                // redirect event — unlike `exec` — carries no cwd of its own.
+                let target = record
+                    .path
+                    .as_ref()
+                    .map(|p| absolute_path(p, &pending.cwd).to_string_lossy().into_owned());
                 let Some((total, data, truncated)) = read_back(record) else {
                     // Special file / unreadable — emit metadata only.
                     obs.send(Event::Redirect {
@@ -510,7 +542,7 @@ impl brush_core::gate::Gate for RecordingGate {
                         cmd_seq: exec_seq,
                         op: record.op.clone(),
                         fd: record.fd,
-                        target: record.path.as_ref().map(|p| p.to_string_lossy().into_owned()),
+                        target,
                         bytes: 0,
                         truncated: false,
                         hash: String::new(),
@@ -524,7 +556,7 @@ impl brush_core::gate::Gate for RecordingGate {
                     cmd_seq: exec_seq,
                     op: record.op.clone(),
                     fd: record.fd,
-                    target: record.path.as_ref().map(|p| p.to_string_lossy().into_owned()),
+                    target,
                     bytes: total,
                     truncated,
                     hash: fnv1a_hex(&data),

nash/tests/observe.rs

@@ -384,6 +384,12 @@ fn redirect_readback_captures_each_operator() {
     let trunc = redirs.iter().find(|e| e["op"] == ">").expect("truncate redirect");
     assert_eq!(decode_preview(trunc), "first\n");
     assert_eq!(trunc["bytes"], 6);
+    // The target is reported ABSOLUTE (docs/NASH.md §5.2). A redirect event carries no cwd of its
+    // own, and the host maps the path to a worktree file — and therefore to a file lock — so a bare
+    // `d.txt` would be unresolvable there. `run_nash` runs in a fresh temp workspace.
+    let target = trunc["target"].as_str().expect("redirect target");
+    assert!(target.starts_with('/'), "target not absolute: {target}");
+    assert!(target.ends_with("/d.txt"), "target lost its file name: {target}");
 
     let append = redirs.iter().find(|e| e["op"] == ">>").expect("append redirect");
     // Append captures ONLY the added bytes, not the whole file.