Robustify a name resolution test (#63259)

* fix TryGetAddrInfo_HostName_TryGetNameInfo() * Fix network test
dotnet · Jan 4, 2022 · f686f65 · f686f65
1 parent a76387e
commit f686f65
Showing 1 changed file with 25 additions and 4 deletions.
diff --git a/src/libraries/System.Net.NameResolution/tests/PalTests/NameResolutionPalTests.cs b/src/libraries/System.Net.NameResolution/tests/PalTests/NameResolutionPalTests.cs
@@ -155,7 +155,18 @@ public void TryGetAddrInfo_LocalHost_TryGetNameInfo()
             Assert.NotNull(aliases);
             Assert.NotNull(addresses);
 
-            string name = NameResolutionPal.TryGetNameInfo(addresses[0], out error, out nativeErrorCode);
+            // Not all addresses returned by TryGetAddInfo can be resolved to host names, depending on network configuration.
+            // However at least one should be.
+            string name = null;
+            foreach(IPAddress address in addresses)
+            {
+                name = NameResolutionPal.TryGetNameInfo(address, out error, out nativeErrorCode);
+                if (error != SocketError.HostNotFound)
+                {
+                    break;
+                }
+            }
+
             Assert.Equal(SocketError.Success, error);
             Assert.NotNull(name);
         }
@@ -181,12 +192,22 @@ public void TryGetAddrInfo_HostName_TryGetNameInfo()
             Assert.NotNull(aliases);
             Assert.NotNull(addresses);
 
-            string name = NameResolutionPal.TryGetNameInfo(addresses[0], out error, out nativeErrorCode);
-            if (error == SocketError.HostNotFound)
+            // Not all addresses returned by TryGetAddInfo can be resolved to host names, depending on network configuration.
+            // However at least one should be.
+            string name = null;
+            foreach(IPAddress address in addresses)
+            {
+                name = NameResolutionPal.TryGetNameInfo(address, out error, out nativeErrorCode);
+                if (error != SocketError.HostNotFound)
+                {
+                    break;
+                }
+            }
+
+            if (error == SocketError.HostNotFound && Environment.OSVersion.Platform == PlatformID.Unix)
             {
                 // On Unix, getaddrinfo returns private ipv4 address for hostname. If the OS doesn't have the
                 // reverse dns lookup entry for this address, getnameinfo returns host not found.
-                Assert.Equal(PlatformID.Unix, Environment.OSVersion.Platform);
                 return;
             }