Speed up project.sh ~21x, 0.703s -> 0.033s

project.sh

@@ -6,40 +6,46 @@ projects_dir=$HOME/Projects
 
 # Print the sorted, de-duplicated list of selectable projects.
 list_projects() {
-  local projects=() dir relative git_dirs kept_roots=() root kept
+  local projects=() dir relative clone worktree projects_real
+
+  # git reports symlink-resolved paths, which need not spell $projects_dir the
+  # way we do, so keep the resolved form around to match them against too.
+  projects_real=$(cd "$projects_dir" 2>/dev/null && pwd -P) ||
+    projects_real=$projects_dir
 
-  # All depth-2 directories without @ are included unconditionally
   for dir in "$projects_dir"/*/*/; do
     [ -d "$dir" ] || continue
     relative="${dir#$projects_dir/}"
     relative="${relative%/}"
-    [[ "$relative" != *@* ]] && projects+=("$relative")
+
+    # All depth-2 directories without @ are included unconditionally
+    if [[ "$relative" != *@* ]]; then
+      projects+=("$relative")
+      continue
+    fi
+
+    # A `repo@branch` directory is the parent of the worktrees hanging off the
+    # `repo` clone, nested one level deeper per `/` in the branch name. Ask
+    # that clone which worktrees it has instead of scanning: git already knows,
+    # whereas a scan deep enough to reach them has to walk every working tree
+    # under $projects_dir to find a handful of entries. Submodules aren't
+    # worktrees, so they never turn up and need no filtering out. `git worktree
+    # list` also names the clone itself, which the branch above already added —
+    # the final sort -u collapses the pair.
+    clone="$projects_dir/${relative%%@*}"
+    while IFS= read -r worktree; do
+      case $worktree in
+        "$projects_dir"/*) worktree=${worktree#"$projects_dir"/} ;;
+        "$projects_real"/*) worktree=${worktree#"$projects_real"/} ;;
+        *) continue ;;
+      esac
+      # Registered but deleted worktrees linger until `git worktree prune`.
+      [ -d "$projects_dir/$worktree" ] || continue
+      projects+=("$worktree")
+    done < <(git -C "$clone" worktree list --porcelain 2>/dev/null |
+      sed -n 's|^worktree ||p')
   done
 
-  # For @ directories, only show the top-most directory that holds a .git
-  # entry. Sorting makes every parent precede its descendants, so once a root
-  # is kept we drop anything nested beneath it — typically a git submodule —
-  # while separate clones and worktrees, each in their own directory, survive.
-  if command -v fd &>/dev/null; then
-    git_dirs=$(fd -H '^\.git$' "$projects_dir" || true)
-  else
-    git_dirs=$(find "$projects_dir" \( -name 'node_modules' -o -name '.git' \) \
-      -prune -name '.git' -print || true)
-  fi
-
-  while IFS= read -r root; do
-    for kept in "${kept_roots[@]}"; do
-      if [[ "$root" == "$kept/"* ]]; then
-        continue 2
-      fi
-    done
-    kept_roots+=("$root")
-    projects+=("$root")
-  done < <(printf '%s\n' "$git_dirs" |
-    grep '@' |
-    sed -E -e "s|^$projects_dir/||" -e 's|/\.git/?$||' |
-    sort -u)
-
   printf '%s\n' "${projects[@]}" | sort -u
 }