Keep main worktree path cached

Author: PawelLipski

git_machete/client/traverse.py

@@ -69,9 +69,7 @@ def _update_worktrees_cache_after_checkout(self, checked_out_branch: LocalBranch
 
     def _switch_to_branch_worktree(
             self,
-            branch: LocalBranchShortName,
-            *,
-            main_worktree_path: str) -> None:
+            branch: LocalBranchShortName) -> None:
         """
         Switch to the worktree where the branch is checked out, or to main worktree if branch is not checked out.
         This may involve changing the current working directory.
@@ -83,6 +81,7 @@ def _switch_to_branch_worktree(
         if worktree_path is None:
             # Branch is not checked out anywhere, need to checkout in main worktree
             # Only cd if we're currently in a different worktree (linked worktree)
+            main_worktree_path = self._git.get_main_worktree_path()
             if current_worktree_root != main_worktree_path:
                 print(f"Changing directory to main worktree at {bold(main_worktree_path)}")
                 os.chdir(main_worktree_path)
@@ -139,8 +138,7 @@ def traverse(
             self._init_code_hosting_client()
             current_user = self.code_hosting_client.get_current_user_login()
 
-        # Store the main worktree path and initial directory for later restoration
-        main_worktree_path = self._git.get_main_worktree_path()
+        # Store the initial directory for later restoration
         initial_branch = nearest_remaining_branch = self._git.get_current_branch()
         initial_worktree_root = self._git.get_root_dir()
 
@@ -151,14 +149,14 @@ def traverse(
             dest = self.root_branch_for(self._git.get_current_branch(), if_unmanaged=PickRoot.FIRST)
             self._print_new_line(False)
             print(f"Checking out the root branch ({bold(dest)})")
-            self._switch_to_branch_worktree(dest, main_worktree_path=main_worktree_path)
+            self._switch_to_branch_worktree(dest)
             current_branch = dest
         elif opt_start_from == TraverseStartFrom.FIRST_ROOT:
             # Note that we already ensured that there is at least one managed branch.
             dest = self.managed_branches[0]
             self._print_new_line(False)
             print(f"Checking out the first root branch ({bold(dest)})")
-            self._switch_to_branch_worktree(dest, main_worktree_path=main_worktree_path)
+            self._switch_to_branch_worktree(dest)
             current_branch = dest
         elif opt_start_from == TraverseStartFrom.HERE:
             current_branch = self._git.get_current_branch()
@@ -168,7 +166,7 @@ def traverse(
             self.expect_in_managed_branches(dest)
             self._print_new_line(False)
             print(f"Checking out branch {bold(dest)}")
-            self._switch_to_branch_worktree(dest, main_worktree_path=main_worktree_path)
+            self._switch_to_branch_worktree(dest)
             current_branch = dest
         else:
             raise UnexpectedMacheteException(f"Unexpected value for opt_start_from: {opt_start_from}")
@@ -245,7 +243,7 @@ def traverse(
             if branch != current_branch and needs_any_action:
                 self._print_new_line(False)
                 print(f"Checking out {bold(branch)}")
-                self._switch_to_branch_worktree(branch, main_worktree_path=main_worktree_path)
+                self._switch_to_branch_worktree(branch)
                 current_branch = branch
                 self._print_new_line(False)
                 self.status(
@@ -471,9 +469,9 @@ def traverse(
         if opt_return_to == TraverseReturnTo.HERE:
             # Return to initial branch
             # No point switching back to initial directory as cwd won't propagate back to the calling shell anyway
-            self._switch_to_branch_worktree(initial_branch, main_worktree_path=main_worktree_path)
+            self._switch_to_branch_worktree(initial_branch)
         elif opt_return_to == TraverseReturnTo.NEAREST_REMAINING:
-            self._switch_to_branch_worktree(nearest_remaining_branch, main_worktree_path=main_worktree_path)
+            self._switch_to_branch_worktree(nearest_remaining_branch)
             # For NEAREST_REMAINING, we stay in the worktree where the branch is checked out
         # otherwise opt_return_to == TraverseReturnTo.STAY, so no action is needed
 

git_machete/git_operations.py

@@ -220,6 +220,7 @@ def __init__(self) -> None:
 
         self.__git_version: Optional[Tuple[int, int, int]] = None
         self.__root_dir: Optional[str] = None
+        self.__main_worktree: Optional[str] = None
         self.__main_git_dir: Optional[str] = None
         self.__worktree_git_dir: Optional[str] = None
 
@@ -254,6 +255,7 @@ def flush_caches(self) -> None:
         self.__remotes_cached = None
         self.__removed_from_remote = None
         self.__root_dir = None
+        self.__main_worktree = None
         self.__short_commit_hash_by_revision_cached = {}
 
     def flush_root_dir_cache(self) -> None:
@@ -630,24 +632,26 @@ def get_main_worktree_path(self) -> str:
         """
         Returns the path to the main worktree (not a linked worktree).
         """
-        if self.get_git_version() < (2, 5):
-            # git worktree command was introduced in git 2.5
-            # If worktrees aren't supported, just return the current root dir
-            return self.get_root_dir()
-
-        # We can't rely on `git rev-parse --git-common-dir`
-        # since in some earlier supported versions of git
-        # this path is apparently printed in a faulty way when dealing with worktrees.
-        # Let's parse the output of of `git worktree list` instead.
-        result = self._popen_git("worktree", "list", "--porcelain")
-
-        # The first worktree in the list is always the main worktree
-        first_entry = result.stdout.splitlines()[0]
-        if first_entry.startswith('worktree '):
-            return first_entry[len('worktree '):]
-        else:
-            raise UnexpectedMacheteException("Could not obtain the main worktree path from "
-                                             f"`git worktree list --porcelain` output (first line: `{first_entry}`)")
+        if not self.__main_worktree:
+            if self.get_git_version() < (2, 5):
+                # git worktree command was introduced in git 2.5
+                # If worktrees aren't supported, just return the current root dir
+                self.__main_worktree = self.get_root_dir()
+            else:
+                # We can't rely on `git rev-parse --git-common-dir`
+                # since in some earlier supported versions of git
+                # this path is apparently printed in a faulty way when dealing with worktrees.
+                # Let's parse the output of of `git worktree list` instead.
+                result = self._popen_git("worktree", "list", "--porcelain")
+
+                # The first worktree in the list is always the main worktree
+                first_entry = result.stdout.splitlines()[0]
+                if first_entry.startswith('worktree '):
+                    self.__main_worktree = first_entry[len('worktree '):]
+                else:
+                    raise UnexpectedMacheteException("Could not obtain the main worktree path from "
+                                                     f"`git worktree list --porcelain` output (first line: `{first_entry}`)")
+        return self.__main_worktree
 
     def checkout(self, branch: LocalBranchShortName) -> None:
         self._run_git("checkout", "--quiet", branch, "--", flush_caches=True)