feat: proxy URI environment variable (#4681)

* Add test extension

This will let us test extension-related features (like the proxy URI).

I removed the environment variables in the script because they override
the ones you set yourself. We still set defaults in constants.ts.

* Add changelog entry for VSCODE_PROXY_URI

* Add terminal test for VSCODE_PROXY_URI

* Update VS Code

This adds the VSCODE_PROXY_URI environment variable.

ci/dev/postinstall.sh

@@ -3,20 +3,30 @@ set -euo pipefail
 
 main() {
   cd "$(dirname "$0")/../.."
+  source ./ci/lib.sh
 
-  echo "Installing code-server test dependencies..."
+  pushd test
+  echo "Installing dependencies for $PWD"
+  yarn install
+  popd
 
   local args=(install)
   if [[ ${CI-} ]]; then
     args+=(--frozen-lockfile)
   fi
 
-  cd test
+  pushd test
+  echo "Installing dependencies for $PWD"
   yarn "${args[@]}"
-  cd ..
+  popd
 
-  cd vendor
-  echo "Installing vendor dependencies..."
+  pushd test/e2e/extensions/test-extension
+  echo "Installing dependencies for $PWD"
+  yarn "${args[@]}"
+  popd
+
+  pushd vendor
+  echo "Installing dependencies for $PWD"
 
   # We install in 'modules' instead of 'node_modules' because VS Code's
   # extensions use a webpack config which cannot differentiate between its own
@@ -33,6 +43,8 @@ main() {
 
   # Finally, run the vendor `postinstall`
   yarn run postinstall
+
+  popd
 }
 
 main "$@"

ci/dev/test-e2e.sh

@@ -13,6 +13,11 @@ main() {
 
   source ./ci/lib.sh
 
+  pushd test/e2e/extensions/test-extension
+  echo "Building test extension"
+  yarn build
+  popd
+
   local dir="$PWD"
   if [[ ! ${CODE_SERVER_TEST_ENTRY-} ]]; then
     echo "Set CODE_SERVER_TEST_ENTRY to test another build of code-server"

ci/dev/test-unit.sh

@@ -6,6 +6,7 @@ main() {
 
   source ./ci/lib.sh
 
+  echo "Building test plugin"
   pushd test/unit/node/test-plugin
   make -s out/index.js
   popd