From 80d00ce4bf8bbcbbdb83e190f697b688c35394ca Mon Sep 17 00:00:00 2001
From: Dave Pearson <davep@davep.org>
Date: Wed, 17 May 2023 10:49:46 +0100
Subject: [PATCH] Logging and experimenting for Windows

---
 src/textual/widgets/_directory_tree.py | 32 +++++++++++++++++---------
 1 file changed, 21 insertions(+), 11 deletions(-)

diff --git a/src/textual/widgets/_directory_tree.py b/src/textual/widgets/_directory_tree.py
index 437811758..0c615f26e 100644
--- a/src/textual/widgets/_directory_tree.py
+++ b/src/textual/widgets/_directory_tree.py
@@ -3,6 +3,7 @@ from __future__ import annotations
 from dataclasses import dataclass
 from pathlib import Path
 from queue import Empty, Queue
+from threading import RLock
 from typing import ClassVar, Iterable, Iterator
 
 from rich.style import Style
@@ -15,6 +16,8 @@ from ..reactive import var
 from ..worker import Worker, get_current_worker
 from ._tree import TOGGLE_STYLE, Tree, TreeNode
 
+read_dir = RLock()
+
 
 @dataclass
 class DirEntry:
@@ -239,6 +242,9 @@ class DirectoryTree(Tree[DirEntry]):
         """
         return paths
 
+    def _tlog(self, message: str) -> None:
+        self.app.call_from_thread(self.log.debug, f"{self.id} - {message}")
+
     def _populate_node(self, node: TreeNode[DirEntry], content: Iterable[Path]) -> None:
         """Populate the given tree node with the given directory content.
 
@@ -268,6 +274,7 @@ class DirectoryTree(Tree[DirEntry]):
             if worker.is_cancelled:
                 break
             yield entry
+            self._tlog(f"Loaded entry {entry} from {location}")
 
     def _load_directory(self, node: TreeNode[DirEntry], worker: Worker) -> None:
         """Load the directory contents for a given node.
@@ -277,14 +284,15 @@ class DirectoryTree(Tree[DirEntry]):
         """
         assert node.data is not None
         node.data.loaded = True
-        self.app.call_from_thread(
-            self._populate_node,
-            node,
-            sorted(
-                self.filter_paths(self._directory_content(node.data.path, worker)),
-                key=lambda path: (not path.is_dir(), path.name.lower()),
-            ),
-        )
+        with read_dir:
+            self.app.call_from_thread(
+                self._populate_node,
+                node,
+                sorted(
+                    self.filter_paths(self._directory_content(node.data.path, worker)),
+                    key=lambda path: (not path.is_dir(), path.name.lower()),
+                ),
+            )
 
     _LOADER_INTERVAL: Final[float] = 0.2
     """How long the loader should block while waiting for queue content."""
@@ -292,12 +300,14 @@ class DirectoryTree(Tree[DirEntry]):
     @work(exclusive=True)
     def _loader(self) -> None:
         """Background loading queue processor."""
+        self._tlog("_loader started")
         worker = get_current_worker()
         while not worker.is_cancelled:
             try:
-                self._load_directory(
-                    self._to_load.get(timeout=self._LOADER_INTERVAL), worker
-                )
+                next_node = self._to_load.get(timeout=self._LOADER_INTERVAL)
+                self._tlog(f"Received {next_node} for loading")
+                self._load_directory(next_node, worker)
+                self._tlog(f"Loaded {next_node}")
             except Empty:
                 pass