vscodium.rb.patch

diff --git a/homebrew-cask/Casks/vscodium.rb b/Casks/vscodium-with-vscode-extensions.rb
index fe11b6463..6a3abdfe1 100644
--- a/homebrew-cask/Casks/v/vscodium.rb
+++ b/Casks/vscodium-with-vscode-extensions.rb
@@ -1,1 +1,1 @@
-cask "vscodium" do
+cask "vscodium-with-vscode-extensions" do
@@ -7,6 +7,6 @@
 
   url "https://github.com/VSCodium/vscodium/releases/download/#{version}/VSCodium.#{arch}.#{version}.dmg"
-  name "VSCodium"
+  name "VSCodium (with original Visual Studio Code Extensions Gallery configuration)"
   desc "Binary releases of VS Code without MS branding/telemetry/licensing"
   homepage "https://github.com/VSCodium/vscodium"
 
@@ -33,7 +33,11 @@
 
   auto_updates true
   depends_on macos: ">= :high_sierra"
+  conflicts_with cask: [
+    "visual-studio-code",
+    "vscodium",
+  ]
 
   app "VSCodium.app"
   binary "#{appdir}/VSCodium.app/Contents/Resources/app/bin/codium"
 
@@ -47,4 +51,36 @@
     "~/Library/Preferences/com.vscodium*.plist",
     "~/Library/Saved Application State/com.vscodium.savedState",
   ]
+
+  postflight do
+    require 'json'
+    require 'fileutils'
+
+    # Reset extensions gallery to mainline Visual Studio Code one by overriding some settings in an external `product.json`.
+    # Support for this was added in [a recent VSCodium change](https://github.com/VSCodium/vscodium/pull/674).
+    product_file_path = "#{Dir.home}/Library/Application Support/VSCodium/product.json"
+
+    # Read exisitng product file if it exists, to not clobber any other settings the user might have.
+    begin
+      product = JSON.load(File.read(product_file_path))
+    # Just use an empty hash otherwise.
+    rescue
+      product = {}
+    end
+
+    # Change needed settings and write back to external file.
+    # Make sure we don't clobber more settings here than necessary, in case there is something else set in the `extensionsGallery` dictionary.
+    extensionsGallerySettings = product['extensionsGallery'] || {}
+    extensionsGallerySettings['serviceUrl'] = 'https://marketplace.visualstudio.com/_apis/public/gallery'
+    extensionsGallerySettings['itemUrl']    = 'https://marketplace.visualstudio.com/items'
+    product['extensionsGallery'] = extensionsGallerySettings
+
+    # Make sure VSCodium's Application Support directory is actually created before we try to write a file into it.
+    FileUtils.mkdir_p(File.dirname(product_file_path))
+    File.write(product_file_path, JSON.pretty_generate(product))
+  end
+
+  # Since we previously forced auto-updating off, we need to alert users about the new functionality.
+  # We don't want to blindly turn auto-updating back on in case the user doesn't want that for other reasons.
+  caveats 'With the latest versions of VSCodium, extensions gallery override settings and auto-updating can now coexist; if you want to turn auto-updating back on, remove the `update.mode` setting from your `settings.json` file.'
 end