[Az.Accounts] Fixed returning duplicate subscription ids.

src/Accounts/Accounts.Test/AzureRMProfileTests.cs

@@ -500,7 +500,7 @@ public void SingleTenantSubscriptionListSucceed()
 
         [Fact]
         [Trait(Category.AcceptanceType, Category.CheckIn)]
-        public void GetSubscriptionListByNameCorrect()
+        public void GetSubscriptionListByNameSameIdCorrect()
         {
             var tenants = new List<string> { DefaultTenant.ToString() };
             var firstList = new List<string> { DefaultSubscription.ToString() };
@@ -514,6 +514,29 @@ public void GetSubscriptionListByNameCorrect()
             client.TryGetSubscriptionListByName(DefaultTenant.ToString(),
                 MockSubscriptionClientFactory.GetSubscriptionNameFromId(DefaultSubscription.ToString()),
                 out subValueList);
+            Assert.Single(subValueList);
+        }
+
+
+        [Fact]
+        [Trait(Category.AcceptanceType, Category.CheckIn)]
+        public void GetSubscriptionListByNameCorrect()
+        {
+            var subId1 = "a11a11aa-aaaa-aaaa-aaaa-aaaa1111aaaa";
+            var subId2 = "aaaa11aa-aaaa-aaaa-aaaa-aaaa1111aaaa";
+
+            var tenants = new List<string> { DefaultTenant.ToString() };
+            var firstList = new List<string> { subId1 };
+            var secondList = new List<string> { subId2 };
+            var thirdList = firstList;
+            var fourthList = firstList;
+            var client = SetupTestEnvironment(tenants, firstList, secondList, thirdList, fourthList);
+            var tenantResults = client.ListTenants();
+            Assert.Single(tenantResults);
+            IEnumerable<IAzureSubscription> subValueList;
+            client.TryGetSubscriptionListByName(DefaultTenant.ToString(),
+                "SameNameForGetSubscriptionByName",
+                out subValueList);
             Assert.Equal(2, subValueList.Count());
         }
 

src/Accounts/Accounts.Test/Mocks/MockSubscriptionClientFactory.cs

@@ -54,6 +54,10 @@ public MockSubscriptionClientFactory()
 
         public static string GetSubscriptionNameFromId(string id)
         {
+            if(id == "a11a11aa-aaaa-aaaa-aaaa-aaaa1111aaaa" || id == "aaaa11aa-aaaa-aaaa-aaaa-aaaa1111aaaa")
+            {
+                return "SameNameForGetSubscriptionByName";
+            }
             return "Sub-" + id;
         }
 

src/Accounts/Accounts/ChangeLog.md

@@ -19,6 +19,7 @@
 -->
 
 ## Upcoming Release
+* Deduplicated subscriptions belonging to multiple tenants while using `Get-AzSubscription` with parameter `SubscriptionName`. [#19427]
 
 ## Version 2.10.0
 * Supported returning all subscriptions with specified name while using `Get-AzSubscription` with parameter `SubscriptionName`. [#19295]

src/Accounts/Accounts/Models/RMProfileClient.cs

@@ -421,11 +421,32 @@ public bool TryGetSubscriptionByName(string tenantId, string subscriptionName, o
             return subscription != null;
         }
 
-        public bool TryGetSubscriptionListByName(string tenantId, string subscriptionName, out IEnumerable<IAzureSubscription> subscriptionList)
+        public bool TryGetSubscriptionListByName(string tenantId, string subscriptionName, out IEnumerable<IAzureSubscription> subscriptions)
         {
-            subscriptionList = ListSubscriptions(tenantId);
-            subscriptionList = subscriptionList.Where(s => s.Name.Equals(subscriptionName, StringComparison.OrdinalIgnoreCase));
-            return subscriptionList.Any();
+            subscriptions = ListSubscriptions(tenantId).Where(s => s.Name.Equals(subscriptionName, StringComparison.OrdinalIgnoreCase));
+            List<IAzureSubscription>  subscriptionList = new List<IAzureSubscription>();
+            HashSet<Guid> existedSubscriptionIds = new HashSet<Guid>();
+
+            // Consider subscription in Home tenant first, exclude duplicate subscriptions by id.
+            foreach(IAzureSubscription subscription in subscriptions)
+            {
+                if (subscription is PSAzureSubscription && subscription.GetTenant() != null 
+                    && subscription.GetHomeTenant().Equals(subscription.GetTenant()) && existedSubscriptionIds.Add(subscription.GetId()))
+                {
+                    subscriptionList.Add(subscription);
+                }
+
+            }
+            // Consider other subscriptions.
+            foreach (IAzureSubscription subscription in subscriptions)
+            {
+                if (existedSubscriptionIds.Add(subscription.GetId()))
+                {
+                    subscriptionList.Add(subscription);
+                }
+            }
+            subscriptions = subscriptionList;
+            return subscriptions.Any();
         }
 
         private IAzureSubscription GetFirstSubscription(string tenantId)