Client: macOS support

Client/LocalDiagrams.py

@@ -31,7 +31,7 @@ from typing import Optional
 
 import httpx
 
-from Core import AssetsDir, ChildEnvironment, DataHome, AppName, IsWindows
+from Core import AssetsDir, ChildEnvironment, DataHome, AppName, Home, IsMac, IsWindows
 
 ToolsDir = DataHome / AppName / "DiagramTools"
 PythonDir = ToolsDir / "Python"
@@ -53,6 +53,12 @@ WindowsBrowsers = [
     r"Google\Chrome\Application\chrome.exe",
     r"BraveSoftware\Brave-Browser\Application\brave.exe",
 ]
+MacBrowsers = [  # in /Applications or ~/Applications
+    "Google Chrome.app/Contents/MacOS/Google Chrome",
+    "Microsoft Edge.app/Contents/MacOS/Microsoft Edge",
+    "Brave Browser.app/Contents/MacOS/Brave Browser",
+    "Chromium.app/Contents/MacOS/Chromium",
+]
 
 
 class DiagramError(Exception):
@@ -169,6 +175,12 @@ def _InstalledBrowser() -> Optional[str]:
                 if Base and (Path(Base) / Relative).is_file():
                     return str(Path(Base) / Relative)
         return None
+    if IsMac:
+        for Base in (Path("/Applications"), Home / "Applications"):
+            for Relative in MacBrowsers:
+                if (Base / Relative).is_file():
+                    return str(Base / Relative)
+        return None
     return next((Found for Name in BrowserNames if (Found := shutil.which(Name))), None)