Validate HttpVersionPolicy enum values on setters

Co-authored-by: MihaZupan <25307628+MihaZupan@users.noreply.github.com>

Author: Copilot

src/libraries/System.Net.Http/src/System/Net/Http/HttpClient.cs

@@ -73,6 +73,10 @@ public HttpVersionPolicy DefaultVersionPolicy
             get => _defaultVersionPolicy;
             set
             {
+                if ((uint)value > (uint)HttpVersionPolicy.RequestVersionExact)
+                {
+                    throw new ArgumentException(SR.Format(SR.net_invalid_enum, nameof(HttpVersionPolicy)), nameof(value));
+                }
                 CheckDisposedOrStarted();
                 _defaultVersionPolicy = value;
             }

src/libraries/System.Net.Http/src/System/Net/Http/HttpRequestMessage.cs

@@ -53,6 +53,10 @@ public HttpVersionPolicy VersionPolicy
             get { return _versionPolicy; }
             set
             {
+                if ((uint)value > (uint)HttpVersionPolicy.RequestVersionExact)
+                {
+                    throw new ArgumentException(SR.Format(SR.net_invalid_enum, nameof(HttpVersionPolicy)), nameof(value));
+                }
                 CheckDisposed();
 
                 _versionPolicy = value;

src/libraries/System.Net.Http/tests/FunctionalTests/HttpClientTest.cs

@@ -1396,6 +1396,20 @@ public void DefaultRequestVersion_InvalidArgument_Throws()
             }
         }
 
+        [Theory]
+        [InlineData((HttpVersionPolicy)(-1))]
+        [InlineData((HttpVersionPolicy)3)]
+        [InlineData((HttpVersionPolicy)int.MaxValue)]
+        public void DefaultVersionPolicy_SetInvalidValue_ThrowsArgumentException(HttpVersionPolicy invalidValue)
+        {
+            using (var client = new HttpClient())
+            {
+                AssertExtensions.Throws<ArgumentException>("value", () => client.DefaultVersionPolicy = invalidValue);
+                client.DefaultVersionPolicy = HttpVersionPolicy.RequestVersionExact; // still usable after
+                Assert.Equal(HttpVersionPolicy.RequestVersionExact, client.DefaultVersionPolicy);
+            }
+        }
+
         [Fact]
         public async Task DefaultRequestVersion_SetAfterUse_Throws()
         {

src/libraries/System.Net.Http/tests/FunctionalTests/HttpRequestMessageTest.cs

@@ -183,6 +183,16 @@ public void Version_SetToNull_ThrowsArgumentNullException()
             Assert.Throws<ArgumentNullException>(() => { rm.Version = null; });
         }
 
+        [Theory]
+        [InlineData((HttpVersionPolicy)(-1))]
+        [InlineData((HttpVersionPolicy)3)]
+        [InlineData((HttpVersionPolicy)int.MaxValue)]
+        public void VersionPolicy_SetInvalidValue_ThrowsArgumentException(HttpVersionPolicy invalidValue)
+        {
+            var rm = new HttpRequestMessage();
+            AssertExtensions.Throws<ArgumentException>("value", () => { rm.VersionPolicy = invalidValue; });
+        }
+
         [Fact]
         public void Method_SetToNull_ThrowsArgumentNullException()
         {