fix: try extensionId first in register{Environment,Package}Manager (microsoft#1484)

Fixes microsoft#1483

This improves both debug and production behavior as it no longer relies
on fragile stack walking (e.g. if one extension ID is a substring of
another, the stack walking could fail)

cc @StellaHuang95

---------

Co-authored-by: Copilot <copilot@github.com>

Author: flying-sheep

api/src/main.ts

@@ -896,9 +896,8 @@ export interface PythonEnvironmentManagerRegistrationApi {
      *
      * @param manager Environment Manager implementation to register.
      * @param options Optional registration options.
-     * @param options.extensionId The extension ID of the calling extension. This is used as a fallback when
-     * automatic extension detection fails, such as during F5 debugging where the extension's file path
-     * does not contain its marketplace ID. If automatic detection succeeds, this value is ignored.
+     * @param options.extensionId The extension ID of the calling extension. When this is not specified,
+     * or when the specified extension cannot be found, the extension ID will be automatically detected.
      * @returns A disposable that can be used to unregister the environment manager.
      * @see {@link EnvironmentManager}
      */
@@ -1005,9 +1004,8 @@ export interface PythonPackageManagerRegistrationApi {
      *
      * @param manager Package Manager implementation to register.
      * @param options Optional registration options.
-     * @param options.extensionId The extension ID of the calling extension. This is used as a fallback when
-     * automatic extension detection fails, such as during F5 debugging where the extension's file path
-     * does not contain its marketplace ID. If automatic detection succeeds, this value is ignored.
+     * @param options.extensionId The extension ID of the calling extension. When this is not specified,
+     * or when the specified extension cannot be found, the extension ID will be automatically detected.
      * @returns A disposable that can be used to unregister the package manager.
      * @see {@link PackageManager}
      */

src/api.ts

@@ -1,7 +1,7 @@
 // Copyright (c) Microsoft Corporation. All rights reserved.
 // Licensed under the MIT License.
 
-import {
+import type {
     Disposable,
     Event,
     FileChangeType,
@@ -890,9 +890,8 @@ export interface PythonEnvironmentManagerRegistrationApi {
      *
      * @param manager Environment Manager implementation to register.
      * @param options Optional registration options.
-     * @param options.extensionId The extension ID of the calling extension. This is used as a fallback when
-     * automatic extension detection fails, such as during F5 debugging where the extension's file path
-     * does not contain its marketplace ID. If automatic detection succeeds, this value is ignored.
+     * @param options.extensionId The extension ID of the calling extension. When this is not specified,
+     * or when the specified extension cannot be found, the extension ID will be automatically detected.
      * @returns A disposable that can be used to unregister the environment manager.
      * @see {@link EnvironmentManager}
      */
@@ -999,9 +998,8 @@ export interface PythonPackageManagerRegistrationApi {
      *
      * @param manager Package Manager implementation to register.
      * @param options Optional registration options.
-     * @param options.extensionId The extension ID of the calling extension. This is used as a fallback when
-     * automatic extension detection fails, such as during F5 debugging where the extension's file path
-     * does not contain its marketplace ID. If automatic detection succeeds, this value is ignored.
+     * @param options.extensionId The extension ID of the calling extension. When this is not specified,
+     * or when the specified extension cannot be found, the extension ID will be automatically detected.
      * @returns A disposable that can be used to unregister the package manager.
      * @see {@link PackageManager}
      */

src/common/utils/frameUtils.ts

@@ -22,15 +22,28 @@ function getFrameData(): FrameData[] {
 }
 
 function getPathFromFrame(frame: FrameData): string {
-    if (frame.filePath && frame.filePath.startsWith('file://')) {
+    if (frame.filePath?.startsWith('file://')) {
         return Uri.parse(frame.filePath).fsPath;
     }
     return frame.filePath;
 }
 
-export function getCallingExtension(extensionIdHint?: string): string {
+export function getCallingExtension(extensionId?: string): string {
     const pythonExts = [ENVS_EXTENSION_ID, PYTHON_EXTENSION_ID];
     const extensions = allExtensions();
+    
+    // Use the provided extensionId when available.
+    // Only accept if it matches an actually loaded extension so we can always return something.
+    if (extensionId) {
+        const hintExt = extensions.find((ext) => ext.id === extensionId);
+        if (hintExt) {
+            traceVerbose(`Using provided extensionId: ${extensionId}`);
+            return extensionId;
+        }
+        traceWarn(`Provided extensionId '${extensionId}' not found in loaded extensions, ignoring`);
+    }
+
+    // Search the stack as a fallback when no extensionId is provided
     const otherExts = extensions.filter((ext) => !pythonExts.includes(ext.id));
     const frames = getFrameData();
 
@@ -94,19 +107,6 @@ export function getCallingExtension(extensionIdHint?: string): string {
         }
     }
 
-    // Use the provided extensionId hint as a fallback (e.g., during F5 debugging where
-    // stack-based detection fails because the file path doesn't contain the extension ID).
-    // Only accept the hint if it matches an actually loaded extension for safety.
-    if (extensionIdHint) {
-        const hintExt = extensions.find((ext) => ext.id === extensionIdHint);
-        if (hintExt) {
-            traceVerbose(`Using provided extensionId hint: ${extensionIdHint}`);
-            extensionIdCache.set(cacheKey, extensionIdHint);
-            return extensionIdHint;
-        }
-        traceWarn(`Provided extensionId hint '${extensionIdHint}' not found in loaded extensions, ignoring`);
-    }
-
     // Fallback - we're likely being called from Python extension or built-in managers
     traceWarn(
         `Could not determine calling extension from stack frames. ` +