From cd51f39d7b9804ef536e108ac3cb81a3e0bed24c Mon Sep 17 00:00:00 2001
From: ispyisail <shane.ringrose@gmail.com>
Date: Fri, 2 Oct 2026 10:05:24 +1300
Subject: [PATCH] qet-mcp: the scripts folder rule as a pure function, tested
 for Windows and macOS

Checked against a real Windows package under Wine: QElectroTech keeps its
data in %APPDATA%\QElectroTech\QElectroTech, next to which the scripts
folder goes.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
---
 misc/qet-mcp/qet_mcp.py      | 30 ++++++++++++++++++++----------
 misc/qet-mcp/test_qet_mcp.py | 22 ++++++++++++++++------
 2 files changed, 36 insertions(+), 16 deletions(-)

diff --git a/misc/qet-mcp/qet_mcp.py b/misc/qet-mcp/qet_mcp.py
index 72222da06..0e994560a 100755
--- a/misc/qet-mcp/qet_mcp.py
+++ b/misc/qet-mcp/qet_mcp.py
@@ -64,7 +64,7 @@ import subprocess
 import sys
 import tempfile
 import xml.etree.ElementTree as ET
-from pathlib import Path, PurePath
+from pathlib import Path, PurePath, PurePosixPath, PureWindowsPath
 
 SERVER_NAME = "qet-mcp"
 SERVER_VERSION = "0.1.0"
@@ -2593,24 +2593,34 @@ SCRIPT_HEADER_HELP = (
     "qet.showMessage() opens a dialog the user has to close.")
 
 
+def default_scripts_dir(os_name: str, platform: str, env, home) -> PurePath:
+    """QETApp::dataDir() + "/scripts" for a given platform.
+
+    dataDir() is Qt's AppDataLocation with organisation and application
+    both "QElectroTech" (main.cpp). Pure, so the Windows and macOS answers
+    are tested on any machine.
+    """
+    if os_name == "nt":
+        appdata = env.get("APPDATA")
+        base = (PureWindowsPath(appdata) if appdata
+                else PureWindowsPath(home, "AppData", "Roaming"))
+    elif platform == "darwin":
+        base = PurePosixPath(home, "Library", "Application Support")
+    else:
+        base = PurePosixPath(env.get("XDG_DATA_HOME") or PurePosixPath(home, ".local", "share"))
+    return base / "QElectroTech" / "QElectroTech" / "scripts"
+
+
 def scripts_dir() -> Path:
     """The folder QElectroTech reads stored scripts from.
 
-    QETApp::dataDir() + "/scripts", where dataDir() is Qt's
-    AppDataLocation for organisation and application "QElectroTech".
     QET_MCP_SCRIPTS_DIR overrides it, for a QElectroTech started with
     --data-dir or a test.
     """
     env = os.environ.get("QET_MCP_SCRIPTS_DIR", "").strip()
     if env:
         return Path(env).expanduser()
-    if os.name == "nt":
-        base = Path(os.environ.get("APPDATA") or Path.home() / "AppData" / "Roaming")
-    elif sys.platform == "darwin":
-        base = Path.home() / "Library" / "Application Support"
-    else:
-        base = Path(os.environ.get("XDG_DATA_HOME") or Path.home() / ".local" / "share")
-    return base / "QElectroTech" / "QElectroTech" / "scripts"
+    return Path(str(default_scripts_dir(os.name, sys.platform, os.environ, str(Path.home()))))
 
 
 def parse_script_header(text: str, script_id: str) -> dict:
diff --git a/misc/qet-mcp/test_qet_mcp.py b/misc/qet-mcp/test_qet_mcp.py
index d65e76626..ebbe49362 100644
--- a/misc/qet-mcp/test_qet_mcp.py
+++ b/misc/qet-mcp/test_qet_mcp.py
@@ -2917,12 +2917,22 @@ class ScriptStore(unittest.TestCase):
                                          "error": "no // ==QETScript== header"}])
 
     def test_default_folder_is_qets_data_dir(self):
-        with mock.patch.dict(os.environ, {"QET_MCP_SCRIPTS_DIR": "",
-                                          "XDG_DATA_HOME": "/x/share"}), \
-                mock.patch.object(m.os, "name", "posix"), \
-                mock.patch.object(m.sys, "platform", "linux"):
-            self.assertEqual(m.scripts_dir(),
-                             Path("/x/share/QElectroTech/QElectroTech/scripts"))
+        """QStandardPaths::AppDataLocation plus the organisation and
+        application names main.cpp sets, on each platform."""
+        from pathlib import PurePosixPath, PureWindowsPath
+        f = m.default_scripts_dir
+        self.assertEqual(f("posix", "linux", {"XDG_DATA_HOME": "/x/share"}, "/home/u"),
+                         PurePosixPath("/x/share/QElectroTech/QElectroTech/scripts"))
+        self.assertEqual(f("posix", "linux", {}, "/home/u"),
+                         PurePosixPath("/home/u/.local/share/QElectroTech/QElectroTech/scripts"))
+        self.assertEqual(f("nt", "win32", {"APPDATA": r"C:\Users\u\AppData\Roaming"}, r"C:\Users\u"),
+                         PureWindowsPath(r"C:\Users\u\AppData\Roaming\QElectroTech\QElectroTech\scripts"))
+        self.assertEqual(f("nt", "win32", {}, r"C:\Users\u"),
+                         PureWindowsPath(r"C:\Users\u\AppData\Roaming\QElectroTech\QElectroTech\scripts"))
+        self.assertEqual(f("posix", "darwin", {}, "/Users/u"),
+                         PurePosixPath("/Users/u/Library/Application Support/QElectroTech/QElectroTech/scripts"))
+        with mock.patch.dict(os.environ, {"QET_MCP_SCRIPTS_DIR": "/elsewhere"}):
+            self.assertEqual(m.scripts_dir(), Path("/elsewhere"))
 
     def test_install_does_not_need_a_binary_without_a_test(self):
         """Only a test run launches QElectroTech; storing a file must not be