Correct dummy implementations and adjust tests

Author: Kartik Raj

src/client/pythonEnvironments/collection/environmentsReducer.ts

@@ -1,7 +1,7 @@
 // Copyright (c) Microsoft Corporation. All rights reserved.
 // Licensed under the MIT License.
 
-import { isEqual } from 'lodash';
+import { cloneDeep, isEqual } from 'lodash';
 import { Event, EventEmitter } from 'vscode';
 import { traceVerbose } from '../../common/logger';
 import { areSameEnvironment, PythonEnvInfo, PythonEnvKind } from '../base/info';
@@ -94,6 +94,8 @@ async function resolveDifferencesInBackground(
     if (!isEqual(oldEnv, merged)) {
         didUpdate.fire({ old: oldEnv, new: merged });
         seen[oldIndex] = merged;
+    } else {
+        const x = 2;
     }
     state.pending -= 1;
     checkIfFinishedAndNotify(state, didUpdate);
@@ -115,10 +117,11 @@ function checkIfFinishedAndNotify(
 }
 
 export function mergeEnvironments(environment: PythonEnvInfo, other: PythonEnvInfo): PythonEnvInfo {
+    const result = cloneDeep(environment);
     // Preserve type information.
     // Possible we identified environment as unknown, but a later provider has identified env type.
     if (environment.kind === PythonEnvKind.Unknown && other.kind && other.kind !== PythonEnvKind.Unknown) {
-        environment.kind = other.kind;
+        result.kind = other.kind;
     }
     const props: (keyof PythonEnvInfo)[] = [
         'version',
@@ -131,11 +134,11 @@ export function mergeEnvironments(environment: PythonEnvInfo, other: PythonEnvIn
         'searchLocation',
     ];
     props.forEach((prop) => {
-        if (!environment[prop] && other[prop]) {
+        if (!result[prop] && other[prop]) {
             // tslint:disable: no-any
             // eslint-disable-next-line @typescript-eslint/no-explicit-any
-            (environment as any)[prop] = other[prop];
+            (result as any)[prop] = other[prop];
         }
     });
-    return environment;
+    return result;
 }

src/test/pythonEnvironments/collection/environmentsReducer.unit.test.ts

@@ -2,6 +2,7 @@
 // Licensed under the MIT License.
 
 import { assert, expect } from 'chai';
+import { isEqual } from 'lodash';
 import * as path from 'path';
 import { EventEmitter } from 'vscode';
 import { PythonEnvInfo, PythonEnvKind } from '../../../client/pythonEnvironments/base/info';
@@ -98,12 +99,14 @@ suite('Environments Reducer', () => {
 
             // Assert
             const env12 = mergeEnvironments(env1, env2);
-            const expectedUpdates = [
-                { old: env1, new: env12 },
-                { old: env12, new: mergeEnvironments(env12, env3) },
-                null,
-            ];
-            assert.deepEqual(expectedUpdates, onUpdatedEvents);
+            const env123 = mergeEnvironments(env12, env3);
+            const expectedUpdates: (PythonEnvUpdatedEvent | null)[] = [];
+            if (isEqual(env12, env123)) {
+                expectedUpdates.push({ old: env1, new: env12 }, null);
+            } else {
+                expectedUpdates.push({ old: env1, new: env12 }, { old: env12, new: env123 }, null);
+            }
+            assert.deepEqual(onUpdatedEvents, expectedUpdates);
         });
 
         test('Updates to environments from the incoming iterator are passed on correctly followed by the null event', async () => {