From 9608770f539d3a01c722818b779d4fcbf28c76ed Mon Sep 17 00:00:00 2001
From: Kartik Raj <karraj@microsoft.com>
Date: Thu, 3 Jun 2021 18:19:32 -0700
Subject: [PATCH 1/2] Ensure configuration service is ready for use before
 using it

---
 src/client/common/configSettings.ts                             | 2 +-
 src/client/common/types.ts                                      | 1 +
 src/client/extensionActivation.ts                               | 2 ++
 .../configSettings/configSettings.pythonPath.unit.test.ts       | 2 +-
 src/test/common/configSettings/configSettings.unit.test.ts      | 2 +-
 5 files changed, 6 insertions(+), 3 deletions(-)

diff --git a/src/client/common/configSettings.ts b/src/client/common/configSettings.ts
index dd3f628a2d4c..e8602be7ded8 100644
--- a/src/client/common/configSettings.ts
+++ b/src/client/common/configSettings.ts
@@ -619,7 +619,7 @@ export class PythonSettings implements IPythonSettings {
         }
     }
 
-    protected initialize(): void {
+    public initialize(): void {
         const onDidChange = () => {
             const currentConfig = this.workspace.getConfiguration('python', this.workspaceRoot);
             this.update(currentConfig);
diff --git a/src/client/common/types.ts b/src/client/common/types.ts
index c194d95a7e8f..5dc17b38208c 100644
--- a/src/client/common/types.ts
+++ b/src/client/common/types.ts
@@ -205,6 +205,7 @@ export interface IPythonSettings {
     readonly logging: ILoggingSettings;
     readonly useIsolation: boolean;
     readonly tensorBoard: ITensorBoardSettings | undefined;
+    initialize(): void;
 }
 
 export interface ITensorBoardSettings {
diff --git a/src/client/extensionActivation.ts b/src/client/extensionActivation.ts
index 4d7e36cd7062..7a2c1fede396 100644
--- a/src/client/extensionActivation.ts
+++ b/src/client/extensionActivation.ts
@@ -175,6 +175,8 @@ async function activateLegacy(ext: ExtensionState): Promise<ActivationResult> {
     const manager = serviceContainer.get<IExtensionActivationManager>(IExtensionActivationManager);
     context.subscriptions.push(manager);
 
+    // Settings are dependent on Experiment service, so we need to initialize it after experiments are activated.
+    serviceContainer.get<IConfigurationService>(IConfigurationService).getSettings().initialize();
     await interpreterManager
         .refresh(workspaceService.hasWorkspaceFolders ? workspaceService.workspaceFolders![0].uri : undefined)
         .catch((ex) => traceError('Python Extension: interpreterManager.refresh', ex));
diff --git a/src/test/common/configSettings/configSettings.pythonPath.unit.test.ts b/src/test/common/configSettings/configSettings.pythonPath.unit.test.ts
index 314282d62e0c..cf54ff32f9ae 100644
--- a/src/test/common/configSettings/configSettings.pythonPath.unit.test.ts
+++ b/src/test/common/configSettings/configSettings.pythonPath.unit.test.ts
@@ -27,7 +27,7 @@ suite('Python Settings - pythonPath', () => {
         protected getPythonExecutable(pythonPath: string) {
             return pythonPath;
         }
-        protected initialize() {
+        public initialize() {
             noop();
         }
     }
diff --git a/src/test/common/configSettings/configSettings.unit.test.ts b/src/test/common/configSettings/configSettings.unit.test.ts
index b1cd6e47cc60..c6eee0771ac8 100644
--- a/src/test/common/configSettings/configSettings.unit.test.ts
+++ b/src/test/common/configSettings/configSettings.unit.test.ts
@@ -33,7 +33,7 @@ suite('Python Settings', async () => {
         public update(pythonSettings: WorkspaceConfiguration) {
             return super.update(pythonSettings);
         }
-        protected initialize() {
+        public initialize() {
             noop();
         }
     }

From dacc570d1a79bcd2587687f6ff2f2ac19596d63d Mon Sep 17 00:00:00 2001
From: Kartik Raj <karraj@microsoft.com>
Date: Thu, 3 Jun 2021 18:30:27 -0700
Subject: [PATCH 2/2] Add news entry

---
 news/2 Fixes/16291.md | 1 +
 1 file changed, 1 insertion(+)
 create mode 100644 news/2 Fixes/16291.md

diff --git a/news/2 Fixes/16291.md b/news/2 Fixes/16291.md
new file mode 100644
index 000000000000..717c9eca09a9
--- /dev/null
+++ b/news/2 Fixes/16291.md	
@@ -0,0 +1 @@
+Ensure selected interpreter doesn't change when the extension is starting up and in experiment.