Disable BinaryFormatter tests in wasm; throw PNSE in wasm

src/libraries/Common/tests/System/Collections/IEnumerable.Generic.Serialization.Tests.cs

@@ -12,6 +12,7 @@ public abstract partial class IEnumerable_Generic_Tests<T> : TestBase<T>
     {
         [Theory]
         [MemberData(nameof(ValidCollectionSizes))]
+        [PlatformSpecific(~TestPlatforms.Browser)] // BinaryFormatter not supported in browser
         public void IGenericSharedAPI_SerializeDeserialize(int count)
         {
             IEnumerable<T> expected = GenericIEnumerableFactory(count);

src/libraries/Common/tests/System/Collections/IEnumerable.NonGeneric.Serialization.Tests.cs

@@ -14,6 +14,7 @@ public abstract partial class IEnumerable_NonGeneric_Tests : TestBase
     {
         [Theory]
         [MemberData(nameof(ValidCollectionSizes))]
+        [PlatformSpecific(~TestPlatforms.Browser)] // BinaryFormatter not supported in browser
         public void IGenericSharedAPI_SerializeDeserialize(int count)
         {
             IEnumerable expected = NonGenericIEnumerableFactory(count);

src/libraries/System.Collections/tests/Generic/Comparers/EqualityComparer.Generic.Serialization.Tests.cs

@@ -13,6 +13,7 @@ namespace System.Collections.Generic.Tests
     public abstract partial class ComparersGenericTests<T>
     {
         [Fact]
+        [PlatformSpecific(~TestPlatforms.Browser)] // BinaryFormatter not supported in browser
         public void EqualityComparer_SerializationRoundtrip()
         {
             var bf = new BinaryFormatter();

src/libraries/System.Collections/tests/Generic/Dictionary/Dictionary.Tests.cs

@@ -401,6 +401,7 @@ private static IDictionary<T, T> CreateDictionary<T>(int size, Func<int, T> keyV
         }
 
         [Fact]
+        [PlatformSpecific(~TestPlatforms.Browser)] // BinaryFormatter not supported in browser
         public void ComparerSerialization()
         {
             // Strings switch between randomized and non-randomized comparers,

src/libraries/System.Collections/tests/Generic/HashSet/HashSet.Generic.Tests.cs

@@ -660,6 +660,7 @@ public void Remove_NonDefaultComparer_ComparerUsed(int capacity)
         #region Serialization
 
         [Fact]
+        [PlatformSpecific(~TestPlatforms.Browser)] // BinaryFormatter not supported in browser
         public void ComparerSerialization()
         {
             // Strings switch between randomized and non-randomized comparers,

src/libraries/System.Runtime.Serialization.Formatters/src/System.Runtime.Serialization.Formatters.csproj

@@ -5,6 +5,10 @@
     <TargetFrameworks>$(NetCoreAppCurrent)</TargetFrameworks>
     <Nullable>enable</Nullable>
   </PropertyGroup>
+  <PropertyGroup>
+    <!-- On certain runtimes BinaryFormatter isn't supported at all. -->
+    <DefineConstants Condition="'$(TargetsBrowser)' == 'true'">$(DefineConstants);BINARYFORMATTER_PNSE</DefineConstants>
+  </PropertyGroup>
   <ItemGroup>
     <Compile Include="System.Runtime.Serialization.Formatters.TypeForwards.cs" />
     <Compile Include="System\Runtime\Serialization\DeserializationEventHandler.cs" />

src/libraries/System.Runtime.Serialization.Formatters/src/System/Runtime/Serialization/Formatters/Binary/BinaryFormatter.cs

@@ -38,10 +38,10 @@ public BinaryFormatter(ISurrogateSelector? selector, StreamingContext context)
 
         public object Deserialize(Stream serializationStream)
         {
-            // don't refactor this check out into a helper method; linker will have difficulty pruning
+            // don't refactor the 'throw' into a helper method; linker will have difficulty trimming
             if (!SerializationInfo.BinaryFormatterEnabled)
             {
-                throw new NotSupportedException(SR.BinaryFormatter_SerializationDisallowed);
+                throw CreateBinaryFormatterDisallowedException();
             }
 
             if (serializationStream == null)
@@ -82,10 +82,10 @@ public object Deserialize(Stream serializationStream)
 
         public void Serialize(Stream serializationStream, object graph)
         {
-            // don't refactor this check out into a helper method; linker will have difficulty pruning
+            // don't refactor the 'throw' into a helper method; linker will have difficulty trimming
             if (!SerializationInfo.BinaryFormatterEnabled)
             {
-                throw new NotSupportedException(SR.BinaryFormatter_SerializationDisallowed);
+                throw CreateBinaryFormatterDisallowedException();
             }
 
             if (serializationStream == null)
@@ -112,5 +112,19 @@ internal static TypeInformation GetTypeInformation(Type type) =>
                 string assemblyName = FormatterServices.GetClrAssemblyName(t, out bool hasTypeForwardedFrom);
                 return new TypeInformation(FormatterServices.GetClrTypeFullName(t), assemblyName, hasTypeForwardedFrom);
             });
+
+        private static Exception CreateBinaryFormatterDisallowedException()
+        {
+            // If we're in an environment where BinaryFormatter never has a
+            // chance of succeeding, use PNSE. Otherwise use regular NSE.
+
+            string message = SR.BinaryFormatter_SerializationDisallowed;
+
+#if BINARYFORMATTER_PNSE
+            throw new PlatformNotSupportedException(message);
+#else
+            throw new NotSupportedException(message);
+#endif
+        }
     }
 }

src/libraries/System.Runtime.Serialization.Formatters/tests/BinaryFormatterTests.cs

@@ -19,6 +19,7 @@
 
 namespace System.Runtime.Serialization.Formatters.Tests
 {
+    [PlatformSpecific(~TestPlatforms.Browser)] // BinaryFormatter not supported in browser
     public partial class BinaryFormatterTests : FileCleanupTestBase
     {
         // On 32-bit we can't test these high inputs as they cause OutOfMemoryExceptions.

src/libraries/System.Runtime.Serialization.Formatters/tests/DisableBitTests.cs

@@ -24,12 +24,12 @@ public static void DisabledAlwaysInBrowser()
 
             MemoryStream ms = new MemoryStream();
             BinaryFormatter bf = new BinaryFormatter();
-            var ex = Assert.Throws<NotSupportedException>(() => bf.Serialize(ms, "A string to serialize."));
+            var ex = Assert.Throws<PlatformNotSupportedException>(() => bf.Serialize(ms, "A string to serialize."));
             Assert.Contains(MoreInfoUrl, ex.Message, StringComparison.Ordinal); // error message should link to the more info URL
 
             // Then test deserialization
 
-            ex = Assert.Throws<NotSupportedException>(() => bf.Deserialize(ms));
+            ex = Assert.Throws<PlatformNotSupportedException>(() => bf.Deserialize(ms));
             Assert.Contains(MoreInfoUrl, ex.Message, StringComparison.Ordinal); // error message should link to the more info URL
         }
 

src/libraries/System.Runtime.Serialization.Formatters/tests/SerializationBinderTests.cs

@@ -23,6 +23,7 @@ public void BindToName_NullDefaults()
         }
 
         [Fact]
+        [PlatformSpecific(~TestPlatforms.Browser)] // BinaryFormatter not supported in browser
         public void BindToType_AllValuesTracked()
         {
             var s = new MemoryStream();

src/libraries/System.Runtime.Serialization.Formatters/tests/SerializationGuardTests.cs

@@ -13,6 +13,7 @@
 
 namespace System.Runtime.Serialization.Formatters.Tests
 {
+    [PlatformSpecific(~TestPlatforms.Browser)] // BinaryFormatter not supported in browser
     public static class SerializationGuardTests
     {
         [Fact]