Setters/adders now throw ArgumentNullException appropriately.

src/AddressBook/AddressBookProtos.cs

@@ -286,6 +286,7 @@ namespace Google.ProtocolBuffers.Examples.AddressBook {
             set { SetNumber(value); }
           }
           public Builder SetNumber(string value) {
+            pb::ThrowHelper.ThrowIfNull(value, "value");
             result.hasNumber = true;
             result.number_ = value;
             return this;
@@ -553,6 +554,7 @@ namespace Google.ProtocolBuffers.Examples.AddressBook {
         set { SetName(value); }
       }
       public Builder SetName(string value) {
+        pb::ThrowHelper.ThrowIfNull(value, "value");
         result.hasName = true;
         result.name_ = value;
         return this;
@@ -589,6 +591,7 @@ namespace Google.ProtocolBuffers.Examples.AddressBook {
         set { SetEmail(value); }
       }
       public Builder SetEmail(string value) {
+        pb::ThrowHelper.ThrowIfNull(value, "value");
         result.hasEmail = true;
         result.email_ = value;
         return this;
@@ -609,18 +612,22 @@ namespace Google.ProtocolBuffers.Examples.AddressBook {
         return result.GetPhone(index);
       }
       public Builder SetPhone(int index, global::Google.ProtocolBuffers.Examples.AddressBook.Person.Types.PhoneNumber value) {
+        pb::ThrowHelper.ThrowIfNull(value, "value");
         result.phone_[index] = value;
         return this;
       }
       public Builder SetPhone(int index, global::Google.ProtocolBuffers.Examples.AddressBook.Person.Types.PhoneNumber.Builder builderForValue) {
+        pb::ThrowHelper.ThrowIfNull(builderForValue, "builderForValue");
         result.phone_[index] = builderForValue.Build();
         return this;
       }
       public Builder AddPhone(global::Google.ProtocolBuffers.Examples.AddressBook.Person.Types.PhoneNumber value) {
+        pb::ThrowHelper.ThrowIfNull(value, "value");
         result.phone_.Add(value);
         return this;
       }
       public Builder AddPhone(global::Google.ProtocolBuffers.Examples.AddressBook.Person.Types.PhoneNumber.Builder builderForValue) {
+        pb::ThrowHelper.ThrowIfNull(builderForValue, "builderForValue");
         result.phone_.Add(builderForValue.Build());
         return this;
       }
@@ -825,18 +832,22 @@ namespace Google.ProtocolBuffers.Examples.AddressBook {
         return result.GetPerson(index);
       }
       public Builder SetPerson(int index, global::Google.ProtocolBuffers.Examples.AddressBook.Person value) {
+        pb::ThrowHelper.ThrowIfNull(value, "value");
         result.person_[index] = value;
         return this;
       }
       public Builder SetPerson(int index, global::Google.ProtocolBuffers.Examples.AddressBook.Person.Builder builderForValue) {
+        pb::ThrowHelper.ThrowIfNull(builderForValue, "builderForValue");
         result.person_[index] = builderForValue.Build();
         return this;
       }
       public Builder AddPerson(global::Google.ProtocolBuffers.Examples.AddressBook.Person value) {
+        pb::ThrowHelper.ThrowIfNull(value, "value");
         result.person_.Add(value);
         return this;
       }
       public Builder AddPerson(global::Google.ProtocolBuffers.Examples.AddressBook.Person.Builder builderForValue) {
+        pb::ThrowHelper.ThrowIfNull(builderForValue, "builderForValue");
         result.person_.Add(builderForValue.Build());
         return this;
       }

src/ProtoGen/FieldGeneratorBase.cs

 using System;
-using Google.ProtocolBuffers.Descriptors;
 using System.Globalization;
+using Google.ProtocolBuffers.Descriptors;
 
 namespace Google.ProtocolBuffers.ProtoGen {
   internal abstract class FieldGeneratorBase : SourceGeneratorBase<FieldDescriptor> {
@@ -87,6 +87,45 @@ namespace Google.ProtocolBuffers.ProtoGen {
       get { return Descriptor.FieldNumber; }
     }
 
+    protected void AddNullCheck(TextGenerator writer) {
+      AddNullCheck(writer, "value");
+    }
+
+    protected void AddNullCheck(TextGenerator writer, string name) {
+      if (IsNullableType) {
+        writer.WriteLine("  pb::ThrowHelper.ThrowIfNull({0}, \"{0}\");", name);
+      }
+    }
+
+    protected bool IsNullableType {
+      get {
+        switch (Descriptor.FieldType) {
+          case FieldType.Float:
+          case FieldType.Double:
+          case FieldType.Int32:
+          case FieldType.Int64:
+          case FieldType.SInt32:
+          case FieldType.SInt64:
+          case FieldType.SFixed32:
+          case FieldType.SFixed64:
+          case FieldType.UInt32:
+          case FieldType.UInt64:
+          case FieldType.Fixed32:
+          case FieldType.Fixed64:
+          case FieldType.Bool:
+          case FieldType.Enum:
+            return false;
+          case FieldType.Bytes:
+          case FieldType.String:
+          case FieldType.Message:
+          case FieldType.Group:
+            return true;
+          default:
+            throw new InvalidOperationException("Invalid field descriptor type");
+        }
+      }
+    }
+
     protected string TypeName {
       get {
         switch (Descriptor.FieldType) {

src/ProtoGen/MessageFieldGenerator.cs

@@ -27,16 +27,19 @@ namespace Google.ProtocolBuffers.ProtoGen {
       writer.WriteLine("  set {{ Set{0}(value); }}", PropertyName);
       writer.WriteLine("}");
       writer.WriteLine("public Builder Set{0}({1} value) {{", PropertyName, TypeName);
+      AddNullCheck(writer);
       writer.WriteLine("  result.has{0} = true;", PropertyName);
       writer.WriteLine("  result.{0}_ = value;", Name);
       writer.WriteLine("  return this;");
       writer.WriteLine("}");
       writer.WriteLine("public Builder Set{0}({1}.Builder builderForValue) {{", PropertyName, TypeName);
+      AddNullCheck(writer, "builderForValue");
       writer.WriteLine("  result.has{0} = true;", PropertyName);
       writer.WriteLine("  result.{0}_ = builderForValue.Build();", Name);
       writer.WriteLine("  return this;");
       writer.WriteLine("}");
       writer.WriteLine("public Builder Merge{0}({1} value) {{", PropertyName, TypeName);
+      AddNullCheck(writer);
       writer.WriteLine("  if (result.Has{0} &&", PropertyName);
       writer.WriteLine("      result.{0}_ != {1}) {{", Name, DefaultValue);
       writer.WriteLine("      result.{0}_ = {1}.CreateBuilder(result.{0}_).MergeFrom(value).BuildPartial();", Name, TypeName);

src/ProtoGen/PrimitiveFieldGenerator.cs

@@ -29,6 +29,7 @@ namespace Google.ProtocolBuffers.ProtoGen {
       writer.WriteLine("  set {{ Set{0}(value); }}", PropertyName);
       writer.WriteLine("}");
       writer.WriteLine("public Builder Set{0}({1} value) {{", PropertyName, TypeName);
+      AddNullCheck(writer);
       writer.WriteLine("  result.has{0} = true;", PropertyName);
       writer.WriteLine("  result.{0}_ = value;", Name);
       writer.WriteLine("  return this;");

src/ProtoGen/RepeatedMessageFieldGenerator.cs

@@ -38,20 +38,24 @@ namespace Google.ProtocolBuffers.ProtoGen {
       writer.WriteLine("  return result.Get{0}(index);", PropertyName);
       writer.WriteLine("}");
       writer.WriteLine("public Builder Set{0}(int index, {1} value) {{", PropertyName, TypeName);
+      AddNullCheck(writer);
       writer.WriteLine("  result.{0}_[index] = value;", Name);
       writer.WriteLine("  return this;");
       writer.WriteLine("}");
       // Extra overload for builder (just on messages)
       writer.WriteLine("public Builder Set{0}(int index, {1}.Builder builderForValue) {{", PropertyName, TypeName);
+      AddNullCheck(writer, "builderForValue");
       writer.WriteLine("  result.{0}_[index] = builderForValue.Build();", Name);
       writer.WriteLine("  return this;");
       writer.WriteLine("}");
       writer.WriteLine("public Builder Add{0}({1} value) {{", PropertyName, TypeName);
+      AddNullCheck(writer);
       writer.WriteLine("  result.{0}_.Add(value);", Name, TypeName);
       writer.WriteLine("  return this;");
       writer.WriteLine("}");
       // Extra overload for builder (just on messages)
       writer.WriteLine("public Builder Add{0}({1}.Builder builderForValue) {{", PropertyName, TypeName);
+      AddNullCheck(writer, "builderForValue");
       writer.WriteLine("  result.{0}_.Add(builderForValue.Build());", Name);
       writer.WriteLine("  return this;");
       writer.WriteLine("}");

src/ProtoGen/RepeatedPrimitiveFieldGenerator.cs

@@ -38,10 +38,12 @@ namespace Google.ProtocolBuffers.ProtoGen {
       writer.WriteLine("  return result.Get{0}(index);", PropertyName);
       writer.WriteLine("}");
       writer.WriteLine("public Builder Set{0}(int index, {1} value) {{", PropertyName, TypeName);
+      AddNullCheck(writer);
       writer.WriteLine("  result.{0}_[index] = value;", Name);
       writer.WriteLine("  return this;");
       writer.WriteLine("}");
       writer.WriteLine("public Builder Add{0}({1} value) {{", PropertyName, TypeName);
+      AddNullCheck(writer);
       writer.WriteLine("  result.{0}_.Add(value);", Name, TypeName);
       writer.WriteLine("  return this;");
       writer.WriteLine("}");

src/ProtocolBuffers.Test/DynamicMessageTest.cs

@@ -53,16 +53,28 @@ namespace Google.ProtocolBuffers {
       reflectionTester.AssertAllFieldsSetViaReflection(message);
     }
 
+    [Test]
+    public void DynamicMessageSettersRejectNull() {
+      IBuilder builder = DynamicMessage.CreateBuilder(TestAllTypes.Descriptor);
+      reflectionTester.AssertReflectionSettersRejectNull(builder);
+	  }
+
     [Test]
     public void DynamicMessageExtensionAccessors() {
-    // We don't need to extensively test DynamicMessage's handling of
-    // extensions because, frankly, it doesn't do anything special with them.
-    // It treats them just like any other fields.
-    IBuilder builder = DynamicMessage.CreateBuilder(TestAllExtensions.Descriptor);
-    extensionsReflectionTester.SetAllFieldsViaReflection(builder);
-    IMessage message = builder.WeakBuild();
-    extensionsReflectionTester.AssertAllFieldsSetViaReflection(message);
-  }
+      // We don't need to extensively test DynamicMessage's handling of
+      // extensions because, frankly, it doesn't do anything special with them.
+      // It treats them just like any other fields.
+      IBuilder builder = DynamicMessage.CreateBuilder(TestAllExtensions.Descriptor);
+      extensionsReflectionTester.SetAllFieldsViaReflection(builder);
+      IMessage message = builder.WeakBuild();
+      extensionsReflectionTester.AssertAllFieldsSetViaReflection(message);
+    }
+
+    [Test]
+    public void DynamicMessageExtensionSettersRejectNull() {
+      IBuilder builder = DynamicMessage.CreateBuilder(TestAllExtensions.Descriptor);
+      extensionsReflectionTester.AssertReflectionSettersRejectNull(builder);
+	  }
 
     [Test]
     public void DynamicMessageRepeatedSetters() {
@@ -73,6 +85,12 @@ namespace Google.ProtocolBuffers {
       reflectionTester.AssertRepeatedFieldsModifiedViaReflection(message);
     }
 
+    [Test]
+    public void DynamicMessageRepeatedSettersRejectNull() {
+      IBuilder builder = DynamicMessage.CreateBuilder(TestAllTypes.Descriptor);
+      reflectionTester.AssertReflectionRepeatedSettersRejectNull(builder);
+    }
+
     [Test]
     public void DynamicMessageDefaults() {
       reflectionTester.AssertClearViaReflection(DynamicMessage.GetDefaultInstance(TestAllTypes.Descriptor));

src/ProtocolBuffers.Test/GeneratedMessageTest.cs

@@ -103,7 +103,20 @@ namespace Google.ProtocolBuffers {
       TestAllTypes message = builder.Build();
       TestUtil.AssertAllFieldsSet(message);
     }
-    
+
+    [Test]
+    public void SettersRejectNull() {
+      TestAllTypes.Builder builder = TestAllTypes.CreateBuilder();
+      TestUtil.AssertArgumentNullException(() => builder.SetOptionalString(null));
+      TestUtil.AssertArgumentNullException(() => builder.SetOptionalBytes(null));
+      TestUtil.AssertArgumentNullException(() => builder.SetOptionalNestedMessage((TestAllTypes.Types.NestedMessage)null));
+      TestUtil.AssertArgumentNullException(() => builder.SetOptionalNestedMessage((TestAllTypes.Types.NestedMessage.Builder)null));
+      TestUtil.AssertArgumentNullException(() => builder.AddRepeatedString(null));
+      TestUtil.AssertArgumentNullException(() => builder.AddRepeatedBytes(null));
+      TestUtil.AssertArgumentNullException(() => builder.AddRepeatedNestedMessage((TestAllTypes.Types.NestedMessage)null));
+      TestUtil.AssertArgumentNullException(() => builder.AddRepeatedNestedMessage((TestAllTypes.Types.NestedMessage.Builder)null));
+    }
+
     [Test]
     public void RepeatedSetters() {
       TestAllTypes.Builder builder = TestAllTypes.CreateBuilder();
@@ -130,6 +143,18 @@ namespace Google.ProtocolBuffers {
       Assert.AreEqual(12, message.GetRepeatedForeignMessage(0).C);
     }
 
+    [Test]
+    public void RepeatedAppendRejectsNull() {
+      TestAllTypes.Builder builder = TestAllTypes.CreateBuilder();
+
+      ForeignMessage foreignMessage = ForeignMessage.CreateBuilder().SetC(12).Build();
+      TestUtil.AssertArgumentNullException(() => builder.AddRangeRepeatedForeignMessage(new[] { foreignMessage, null }));
+      TestUtil.AssertArgumentNullException(() => builder.AddRangeRepeatedForeignMessage(null));
+      TestUtil.AssertArgumentNullException(() => builder.AddRangeRepeatedForeignEnum(null));
+      TestUtil.AssertArgumentNullException(() => builder.AddRangeRepeatedString(new[] { "one", null }));
+      TestUtil.AssertArgumentNullException(() => builder.AddRangeRepeatedBytes(new[] { TestUtil.ToBytes("one"), null }));
+    }
+
     [Test]
     public void SettingForeignMessageUsingBuilder() {
       TestAllTypes message = TestAllTypes.CreateBuilder()
@@ -181,6 +206,11 @@ namespace Google.ProtocolBuffers {
       TestUtil.AssertAllFieldsSet(message);
     }
 
+    [Test]
+    public void ReflectionSettersRejectNull() {
+      TestAllTypes.Builder builder = TestAllTypes.CreateBuilder();
+      reflectionTester.AssertReflectionSettersRejectNull(builder);
+    }
     [Test]
     public void ReflectionRepeatedSetters() {
       TestAllTypes.Builder builder = TestAllTypes.CreateBuilder();
@@ -190,6 +220,12 @@ namespace Google.ProtocolBuffers {
       TestUtil.AssertRepeatedFieldsModified(message);
     }
 
+    [Test]
+    public void TestReflectionRepeatedSettersRejectNull() {
+      TestAllTypes.Builder builder = TestAllTypes.CreateBuilder();
+      reflectionTester.AssertReflectionRepeatedSettersRejectNull(builder);
+    }
+
     [Test]
     public void ReflectionDefaults() {
       reflectionTester.AssertClearViaReflection(TestAllTypes.DefaultInstance);
@@ -237,6 +273,12 @@ namespace Google.ProtocolBuffers {
       TestUtil.AssertAllExtensionsSet(message);
     }
 
+    [Test]
+    public void ExtensionReflectionSettersRejectNull() {
+      TestAllExtensions.Builder builder = TestAllExtensions.CreateBuilder();
+      extensionsReflectionTester.AssertReflectionSettersRejectNull(builder);
+    }
+
     [Test]
     public void ExtensionReflectionRepeatedSetters() {
       TestAllExtensions.Builder builder = TestAllExtensions.CreateBuilder();
@@ -246,6 +288,12 @@ namespace Google.ProtocolBuffers {
       TestUtil.AssertRepeatedExtensionsModified(message);
     }
 
+    [Test]
+    public void ExtensionReflectionRepeatedSettersRejectNull() {
+      TestAllExtensions.Builder builder = TestAllExtensions.CreateBuilder();
+      extensionsReflectionTester.AssertReflectionRepeatedSettersRejectNull(builder);
+    }
+
     [Test]
     public void ExtensionReflectionDefaults() {
       extensionsReflectionTester.AssertClearViaReflection(TestAllExtensions.DefaultInstance);
@@ -265,6 +313,18 @@ namespace Google.ProtocolBuffers {
           .GetExtensionCount(UnitTestProtoFile.RepeatedInt32Extension));
     }
 
+    /* Reinstate this test in the commit where it's fixed...
+    [Test]
+    public void ExtensionMergeFrom() {
+      TestAllExtensions original = TestAllExtensions.CreateBuilder()
+          .SetExtension(UnitTestProtoFile.OptionalInt32Extension, 1).Build();
+      TestAllExtensions merged =
+          TestAllExtensions.CreateBuilder().MergeFrom(original).Build();
+      Assert.IsTrue((merged.HasExtension(UnitTestProtoFile.OptionalInt32Extension)));
+      Assert.AreEqual(1, (int)merged.GetExtension(UnitTestProtoFile.OptionalInt32Extension));
+    }
+    */
+
     /* Removed multiple files option for the moment
     [Test]
     public void MultipleFilesOption() {

src/ProtocolBuffers.Test/ReflectionTester.cs

@@ -810,5 +810,37 @@ namespace Google.ProtocolBuffers {
       Assert.AreEqual("524", message[f("repeated_string_piece"), 1]);
       Assert.AreEqual("525", message[f("repeated_cord"), 1]);
     }
+
+    /// <summary>
+    /// Verifies that the reflection setters for the given Builder object throw an
+    /// ArgumentNullException if they are passed a null value. 
+    /// </summary>
+    public void AssertReflectionSettersRejectNull(IBuilder builder) {
+      TestUtil.AssertArgumentNullException(() => builder[f("optional_string")] = null);
+      TestUtil.AssertArgumentNullException(() => builder[f("optional_bytes")] = null);
+      TestUtil.AssertArgumentNullException(() => builder[f("optional_nested_enum")] = null);
+      TestUtil.AssertArgumentNullException(() => builder[f("optional_nested_message")] = null);
+      TestUtil.AssertArgumentNullException(() => builder[f("optional_nested_message")] = null);
+      TestUtil.AssertArgumentNullException(() => builder.WeakAddRepeatedField(f("repeated_string"), null));
+      TestUtil.AssertArgumentNullException(() => builder.WeakAddRepeatedField(f("repeated_bytes"), null));
+      TestUtil.AssertArgumentNullException(() => builder.WeakAddRepeatedField(f("repeated_nested_enum"), null));
+      TestUtil.AssertArgumentNullException(() => builder.WeakAddRepeatedField(f("repeated_nested_message"), null));
+    }
+
+    /// <summary>
+    /// Verifies that the reflection repeated setters for the given Builder object throw an
+    /// ArgumentNullException if they are passed a null value.
+    /// </summary>
+    public void AssertReflectionRepeatedSettersRejectNull(IBuilder builder) {
+      builder.WeakAddRepeatedField(f("repeated_string"), "one");
+      TestUtil.AssertArgumentNullException(() => builder.SetRepeatedField(f("repeated_string"), 0, null));
+      builder.WeakAddRepeatedField(f("repeated_bytes"), TestUtil.ToBytes("one"));
+      TestUtil.AssertArgumentNullException(() => builder.SetRepeatedField(f("repeated_bytes"), 0, null));
+      builder.WeakAddRepeatedField(f("repeated_nested_enum"), nestedBaz);
+      TestUtil.AssertArgumentNullException(() => builder.SetRepeatedField(f("repeated_nested_enum"), 0, null));
+      builder.WeakAddRepeatedField(f("repeated_nested_message"),
+          new TestAllTypes.Types.NestedMessage.Builder { Bb = 218 }.Build());
+      TestUtil.AssertArgumentNullException(() => builder.SetRepeatedField(f("repeated_nested_message"), 0, null));
+    }
   }
 }

src/ProtocolBuffers.Test/TestProtos/UnitTestCustomOptionsProtoFile.cs

@@ -397,6 +397,7 @@ namespace Google.ProtocolBuffers.TestProtos {
         set { SetField1(value); }
       }
       public Builder SetField1(string value) {
+        pb::ThrowHelper.ThrowIfNull(value, "value");
         result.hasField1 = true;
         result.field1_ = value;
         return this;
@@ -1593,16 +1594,19 @@ namespace Google.ProtocolBuffers.TestProtos {
         set { SetBar(value); }
       }
       public Builder SetBar(global::Google.ProtocolBuffers.TestProtos.ComplexOptionType1 value) {
+        pb::ThrowHelper.ThrowIfNull(value, "value");
         result.hasBar = true;
         result.bar_ = value;
         return this;
       }
       public Builder SetBar(global::Google.ProtocolBuffers.TestProtos.ComplexOptionType1.Builder builderForValue) {
+        pb::ThrowHelper.ThrowIfNull(builderForValue, "builderForValue");
         result.hasBar = true;
         result.bar_ = builderForValue.Build();
         return this;
       }
       public Builder MergeBar(global::Google.ProtocolBuffers.TestProtos.ComplexOptionType1 value) {
+        pb::ThrowHelper.ThrowIfNull(value, "value");
         if (result.HasBar &&
             result.bar_ != global::Google.ProtocolBuffers.TestProtos.ComplexOptionType1.DefaultInstance) {
             result.bar_ = global::Google.ProtocolBuffers.TestProtos.ComplexOptionType1.CreateBuilder(result.bar_).MergeFrom(value).BuildPartial();
@@ -1644,16 +1648,19 @@ namespace Google.ProtocolBuffers.TestProtos {
         set { SetFred(value); }
       }
       public Builder SetFred(global::Google.ProtocolBuffers.TestProtos.ComplexOptionType2.Types.ComplexOptionType4 value) {
+        pb::ThrowHelper.ThrowIfNull(value, "value");
         result.hasFred = true;
         result.fred_ = value;
         return this;
       }
       public Builder SetFred(global::Google.ProtocolBuffers.TestProtos.ComplexOptionType2.Types.ComplexOptionType4.Builder builderForValue) {
+        pb::ThrowHelper.ThrowIfNull(builderForValue, "builderForValue");
         result.hasFred = true;
         result.fred_ = builderForValue.Build();
         return this;
       }
       public Builder MergeFred(global::Google.ProtocolBuffers.TestProtos.ComplexOptionType2.Types.ComplexOptionType4 value) {
+        pb::ThrowHelper.ThrowIfNull(value, "value");
         if (result.HasFred &&
             result.fred_ != global::Google.ProtocolBuffers.TestProtos.ComplexOptionType2.Types.ComplexOptionType4.DefaultInstance) {
             result.fred_ = global::Google.ProtocolBuffers.TestProtos.ComplexOptionType2.Types.ComplexOptionType4.CreateBuilder(result.fred_).MergeFrom(value).BuildPartial();
@@ -1925,16 +1932,19 @@ namespace Google.ProtocolBuffers.TestProtos {
         set { SetComplexOptionType5(value); }
       }
       public Builder SetComplexOptionType5(global::Google.ProtocolBuffers.TestProtos.ComplexOptionType3.Types.ComplexOptionType5 value) {
+        pb::ThrowHelper.ThrowIfNull(value, "value");
         result.hasComplexOptionType5 = true;
         result.complexOptionType5_ = value;
         return this;
       }
       public Builder SetComplexOptionType5(global::Google.ProtocolBuffers.TestProtos.ComplexOptionType3.Types.ComplexOptionType5.Builder builderForValue) {
+        pb::ThrowHelper.ThrowIfNull(builderForValue, "builderForValue");
         result.hasComplexOptionType5 = true;
         result.complexOptionType5_ = builderForValue.Build();
         return this;
       }
       public Builder MergeComplexOptionType5(global::Google.ProtocolBuffers.TestProtos.ComplexOptionType3.Types.ComplexOptionType5 value) {
+        pb::ThrowHelper.ThrowIfNull(value, "value");
         if (result.HasComplexOptionType5 &&
             result.complexOptionType5_ != global::Google.ProtocolBuffers.TestProtos.ComplexOptionType3.Types.ComplexOptionType5.DefaultInstance) {
             result.complexOptionType5_ = global::Google.ProtocolBuffers.TestProtos.ComplexOptionType3.Types.ComplexOptionType5.CreateBuilder(result.complexOptionType5_).MergeFrom(value).BuildPartial();

src/ProtocolBuffers.Test/TestProtos/UnitTestEmbedOptimizeForProtoFile.cs

@@ -256,16 +256,19 @@ namespace Google.ProtocolBuffers.TestProtos {
         set { SetOptionalMessage(value); }
       }
       public Builder SetOptionalMessage(global::Google.ProtocolBuffers.TestProtos.TestOptimizedForSize value) {
+        pb::ThrowHelper.ThrowIfNull(value, "value");
         result.hasOptionalMessage = true;
         result.optionalMessage_ = value;
         return this;
       }
       public Builder SetOptionalMessage(global::Google.ProtocolBuffers.TestProtos.TestOptimizedForSize.Builder builderForValue) {
+        pb::ThrowHelper.ThrowIfNull(builderForValue, "builderForValue");
         result.hasOptionalMessage = true;
         result.optionalMessage_ = builderForValue.Build();
         return this;
       }
       public Builder MergeOptionalMessage(global::Google.ProtocolBuffers.TestProtos.TestOptimizedForSize value) {
+        pb::ThrowHelper.ThrowIfNull(value, "value");
         if (result.HasOptionalMessage &&
             result.optionalMessage_ != global::Google.ProtocolBuffers.TestProtos.TestOptimizedForSize.DefaultInstance) {
             result.optionalMessage_ = global::Google.ProtocolBuffers.TestProtos.TestOptimizedForSize.CreateBuilder(result.optionalMessage_).MergeFrom(value).BuildPartial();
@@ -291,18 +294,22 @@ namespace Google.ProtocolBuffers.TestProtos {
         return result.GetRepeatedMessage(index);
       }
       public Builder SetRepeatedMessage(int index, global::Google.ProtocolBuffers.TestProtos.TestOptimizedForSize value) {
+        pb::ThrowHelper.ThrowIfNull(value, "value");
         result.repeatedMessage_[index] = value;
         return this;
       }
       public Builder SetRepeatedMessage(int index, global::Google.ProtocolBuffers.TestProtos.TestOptimizedForSize.Builder builderForValue) {
+        pb::ThrowHelper.ThrowIfNull(builderForValue, "builderForValue");
         result.repeatedMessage_[index] = builderForValue.Build();
         return this;
       }
       public Builder AddRepeatedMessage(global::Google.ProtocolBuffers.TestProtos.TestOptimizedForSize value) {
+        pb::ThrowHelper.ThrowIfNull(value, "value");
         result.repeatedMessage_.Add(value);
         return this;
       }
       public Builder AddRepeatedMessage(global::Google.ProtocolBuffers.TestProtos.TestOptimizedForSize.Builder builderForValue) {
+        pb::ThrowHelper.ThrowIfNull(builderForValue, "builderForValue");
         result.repeatedMessage_.Add(builderForValue.Build());
         return this;
       }

src/ProtocolBuffers.Test/TestProtos/UnitTestMessageSetProtoFile.cs

@@ -410,16 +410,19 @@ namespace Google.ProtocolBuffers.TestProtos {
         set { SetMessageSet(value); }
       }
       public Builder SetMessageSet(global::Google.ProtocolBuffers.TestProtos.TestMessageSet value) {
+        pb::ThrowHelper.ThrowIfNull(value, "value");
         result.hasMessageSet = true;
         result.messageSet_ = value;
         return this;
       }
       public Builder SetMessageSet(global::Google.ProtocolBuffers.TestProtos.TestMessageSet.Builder builderForValue) {
+        pb::ThrowHelper.ThrowIfNull(builderForValue, "builderForValue");
         result.hasMessageSet = true;
         result.messageSet_ = builderForValue.Build();
         return this;
       }
       public Builder MergeMessageSet(global::Google.ProtocolBuffers.TestProtos.TestMessageSet value) {
+        pb::ThrowHelper.ThrowIfNull(value, "value");
         if (result.HasMessageSet &&
             result.messageSet_ != global::Google.ProtocolBuffers.TestProtos.TestMessageSet.DefaultInstance) {
             result.messageSet_ = global::Google.ProtocolBuffers.TestProtos.TestMessageSet.CreateBuilder(result.messageSet_).MergeFrom(value).BuildPartial();
@@ -813,6 +816,7 @@ namespace Google.ProtocolBuffers.TestProtos {
         set { SetStr(value); }
       }
       public Builder SetStr(string value) {
+        pb::ThrowHelper.ThrowIfNull(value, "value");
         result.hasStr = true;
         result.str_ = value;
         return this;
@@ -1071,6 +1075,7 @@ namespace Google.ProtocolBuffers.TestProtos {
             set { SetMessage(value); }
           }
           public Builder SetMessage(pb::ByteString value) {
+            pb::ThrowHelper.ThrowIfNull(value, "value");
             result.hasMessage = true;
             result.message_ = value;
             return this;
@@ -1251,18 +1256,22 @@ namespace Google.ProtocolBuffers.TestProtos {
         return result.GetItem(index);
       }
       public Builder SetItem(int index, global::Google.ProtocolBuffers.TestProtos.RawMessageSet.Types.Item value) {
+        pb::ThrowHelper.ThrowIfNull(value, "value");
         result.item_[index] = value;
         return this;
       }
       public Builder SetItem(int index, global::Google.ProtocolBuffers.TestProtos.RawMessageSet.Types.Item.Builder builderForValue) {
+        pb::ThrowHelper.ThrowIfNull(builderForValue, "builderForValue");
         result.item_[index] = builderForValue.Build();
         return this;
       }
       public Builder AddItem(global::Google.ProtocolBuffers.TestProtos.RawMessageSet.Types.Item value) {
+        pb::ThrowHelper.ThrowIfNull(value, "value");
         result.item_.Add(value);
         return this;
       }
       public Builder AddItem(global::Google.ProtocolBuffers.TestProtos.RawMessageSet.Types.Item.Builder builderForValue) {
+        pb::ThrowHelper.ThrowIfNull(builderForValue, "builderForValue");
         result.item_.Add(builderForValue.Build());
         return this;
       }

src/ProtocolBuffers.Test/TestProtos/UnitTestOptimizeForProtoFile.cs

@@ -189,16 +189,19 @@ namespace Google.ProtocolBuffers.TestProtos {
         set { SetMsg(value); }
       }
       public Builder SetMsg(global::Google.ProtocolBuffers.TestProtos.ForeignMessage value) {
+        pb::ThrowHelper.ThrowIfNull(value, "value");
         result.hasMsg = true;
         result.msg_ = value;
         return this;
       }
       public Builder SetMsg(global::Google.ProtocolBuffers.TestProtos.ForeignMessage.Builder builderForValue) {
+        pb::ThrowHelper.ThrowIfNull(builderForValue, "builderForValue");
         result.hasMsg = true;
         result.msg_ = builderForValue.Build();
         return this;
       }
       public Builder MergeMsg(global::Google.ProtocolBuffers.TestProtos.ForeignMessage value) {
+        pb::ThrowHelper.ThrowIfNull(value, "value");
         if (result.HasMsg &&
             result.msg_ != global::Google.ProtocolBuffers.TestProtos.ForeignMessage.DefaultInstance) {
             result.msg_ = global::Google.ProtocolBuffers.TestProtos.ForeignMessage.CreateBuilder(result.msg_).MergeFrom(value).BuildPartial();
@@ -438,16 +441,19 @@ namespace Google.ProtocolBuffers.TestProtos {
         set { SetO(value); }
       }
       public Builder SetO(global::Google.ProtocolBuffers.TestProtos.TestRequiredOptimizedForSize value) {
+        pb::ThrowHelper.ThrowIfNull(value, "value");
         result.hasO = true;
         result.o_ = value;
         return this;
       }
       public Builder SetO(global::Google.ProtocolBuffers.TestProtos.TestRequiredOptimizedForSize.Builder builderForValue) {
+        pb::ThrowHelper.ThrowIfNull(builderForValue, "builderForValue");
         result.hasO = true;
         result.o_ = builderForValue.Build();
         return this;
       }
       public Builder MergeO(global::Google.ProtocolBuffers.TestProtos.TestRequiredOptimizedForSize value) {
+        pb::ThrowHelper.ThrowIfNull(value, "value");
         if (result.HasO &&
             result.o_ != global::Google.ProtocolBuffers.TestProtos.TestRequiredOptimizedForSize.DefaultInstance) {
             result.o_ = global::Google.ProtocolBuffers.TestProtos.TestRequiredOptimizedForSize.CreateBuilder(result.o_).MergeFrom(value).BuildPartial();

src/ProtocolBuffers.Test/TestUtil.cs

@@ -1383,5 +1383,14 @@ namespace Google.ProtocolBuffers {
       }
       return bytes;
     }
+
+    internal static void AssertArgumentNullException(Action action) {
+      try {
+        action();
+        Assert.Fail("Exception was not thrown");
+      } catch (ArgumentNullException) {
+        // We expect this exception.
+      }
+    }
   }
 }

src/ProtocolBuffers.Test/TextFormatTest.cs

@@ -499,5 +499,29 @@ namespace Google.ProtocolBuffers {
       AssertFormatException(() => TextFormat.ParseUInt64("-1"));
       AssertFormatException(() => TextFormat.ParseInt32("abcd"));
     }
+
+    [Test]
+    public void ParseLongString() {
+      string longText =
+        "123456789012345678901234567890123456789012345678901234567890" +
+        "123456789012345678901234567890123456789012345678901234567890" +
+        "123456789012345678901234567890123456789012345678901234567890" +
+        "123456789012345678901234567890123456789012345678901234567890" +
+        "123456789012345678901234567890123456789012345678901234567890" +
+        "123456789012345678901234567890123456789012345678901234567890" +
+        "123456789012345678901234567890123456789012345678901234567890" +
+        "123456789012345678901234567890123456789012345678901234567890" +
+        "123456789012345678901234567890123456789012345678901234567890" +
+        "123456789012345678901234567890123456789012345678901234567890" +
+        "123456789012345678901234567890123456789012345678901234567890" +
+        "123456789012345678901234567890123456789012345678901234567890" +
+        "123456789012345678901234567890123456789012345678901234567890" +
+        "123456789012345678901234567890123456789012345678901234567890" +
+        "123456789012345678901234567890123456789012345678901234567890" +
+        "123456789012345678901234567890123456789012345678901234567890";
+      TestAllTypes.Builder builder = TestAllTypes.CreateBuilder();
+      TextFormat.Merge("optional_string: \"" + longText + "\"", builder);
+      Assert.AreEqual(longText, builder.OptionalString);
+    }
   }
 }

src/ProtocolBuffers/DescriptorProtos/CSharpOptions.cs

@@ -192,6 +192,7 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
         set { SetNamespace(value); }
       }
       public Builder SetNamespace(string value) {
+        pb::ThrowHelper.ThrowIfNull(value, "value");
         result.hasNamespace = true;
         result.namespace_ = value;
         return this;
@@ -210,6 +211,7 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
         set { SetUmbrellaClassname(value); }
       }
       public Builder SetUmbrellaClassname(string value) {
+        pb::ThrowHelper.ThrowIfNull(value, "value");
         result.hasUmbrellaClassname = true;
         result.umbrellaClassname_ = value;
         return this;
@@ -381,6 +383,7 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
         set { SetPropertyName(value); }
       }
       public Builder SetPropertyName(string value) {
+        pb::ThrowHelper.ThrowIfNull(value, "value");
         result.hasPropertyName = true;
         result.propertyName_ = value;
         return this;

src/ProtocolBuffers/FieldAccess/RepeatedEnumAccessor.cs

@@ -66,10 +66,12 @@ namespace Google.ProtocolBuffers.FieldAccess {
     }
 
     public override void AddRepeated(TBuilder builder, object value) {
-      base.AddRepeated(builder, ((EnumValueDescriptor) value).Number);
+      ThrowHelper.ThrowIfNull(value, "value");
+      base.AddRepeated(builder, ((EnumValueDescriptor)value).Number);
     }
 
     public override void SetRepeated(TBuilder builder, int index, object value) {
+      ThrowHelper.ThrowIfNull(value, "value");
       base.SetRepeated(builder, index, ((EnumValueDescriptor) value).Number);
     }
   }

src/ProtocolBuffers/FieldAccess/RepeatedMessageAccessor.cs

@@ -64,7 +64,7 @@ namespace Google.ProtocolBuffers.FieldAccess {
     /// which may already be of the right type or may be a dynamic message.
     /// </summary>
     private object CoerceType(object value) {
-
+      ThrowHelper.ThrowIfNull(value, "value");
       // If it's already of the right type, we're done
       if (ClrType.IsInstanceOfType(value)) {
         return value;

src/ProtocolBuffers/FieldAccess/RepeatedPrimitiveAccessor.cs

@@ -122,10 +122,12 @@ namespace Google.ProtocolBuffers.FieldAccess {
     }
 
     public virtual void SetRepeated(TBuilder builder, int index, object value) {
-      setElementMethod.Invoke(builder, new object[] {index, value} );
+      ThrowHelper.ThrowIfNull(value, "value");
+      setElementMethod.Invoke(builder, new object[] { index, value });
     }
 
     public virtual void AddRepeated(TBuilder builder, object value) {
+      ThrowHelper.ThrowIfNull(value, "value");
       addValueDelegate(builder, value);
     }
 

src/ProtocolBuffers/FieldAccess/SingleEnumAccessor.cs

@@ -63,6 +63,7 @@ namespace Google.ProtocolBuffers.FieldAccess {
     /// from an EnumValueDescriptor parameter.
     /// </summary>
     public override void SetValue(TBuilder builder, object value) {
+      ThrowHelper.ThrowIfNull(value, "value");
       EnumValueDescriptor valueDescriptor = (EnumValueDescriptor) value;
       base.SetValue(builder, valueDescriptor.Number);
     }

src/ProtocolBuffers/FieldAccess/SingleMessageAccessor.cs

@@ -60,7 +60,7 @@ namespace Google.ProtocolBuffers.FieldAccess {
     /// which may already be of the right type or may be a dynamic message.
     /// </summary>
     private object CoerceType(object value) {
-
+      ThrowHelper.ThrowIfNull(value, "value");
       // If it's already of the right type, we're done
       if (ClrType.IsInstanceOfType(value)) {
         return value;

src/ProtocolBuffers/FieldSet.cs

@@ -413,7 +413,9 @@ namespace Google.ProtocolBuffers {
     /// element type, not whether it's a list.
     /// </remarks>
     /// <exception cref="ArgumentException">The value is not of the right type.</exception>
+    /// <exception cref="ArgumentNullException">The value is null.</exception>
     private static void VerifyType(FieldDescriptor field, object value) {
+      ThrowHelper.ThrowIfNull(value, "value");
       bool isValid = false;
       switch (field.MappedType) {
         case MappedType.Int32:       isValid = value is int;    break;

src/ProtocolBuffers/GeneratedBuilder.cs

@@ -78,7 +78,13 @@ namespace Google.ProtocolBuffers {
     /// <summary>
     /// Adds all of the specified values to the given collection.
     /// </summary>
+    /// <exception cref="ArgumentNullException">Any element of the list is null</exception>
     protected void AddRange<T>(IEnumerable<T> source, IList<T> destination) {
+      ThrowHelper.ThrowIfNull(source);
+      // We only need to check this for nullable types.
+      if (default(T) == null) {
+        ThrowHelper.ThrowIfAnyNull(source);
+      }
       List<T> list = destination as List<T>;
       if (list != null) {
         list.AddRange(source);

src/ProtocolBuffers/ProtocolBuffers.csproj

@@ -104,6 +104,7 @@
     <Compile Include="TextFormat.cs" />
     <Compile Include="TextGenerator.cs" />
     <Compile Include="TextTokenizer.cs" />
+    <Compile Include="ThrowHelper.cs" />
     <Compile Include="UninitializedMessageException.cs" />
     <Compile Include="UnknownField.cs" />
     <Compile Include="UnknownFieldSet.cs" />

src/ProtocolBuffers/ThrowHelper.cs

+using System;
+using System.Collections.Generic;
+using System.Text;
+
+namespace Google.ProtocolBuffers {
+  /// <summary>
+  /// Helper methods for throwing exceptions
+  /// </summary>
+  public static class ThrowHelper {
+
+    /// <summary>
+    /// Throws an ArgumentNullException if the given value is null.
+    /// </summary>
+    public static void ThrowIfNull(object value, string name) {
+      if (value == null) {
+        throw new ArgumentNullException(name);
+      }
+    }
+
+    /// <summary>
+    /// Throws an ArgumentNullException if the given value is null.
+    /// </summary>
+    public static void ThrowIfNull(object value) {
+      if (value == null) {
+        throw new ArgumentNullException();
+      }
+    }
+
+    /// <summary>
+    /// Throws an ArgumentNullException if the given value or any element within it is null.
+    /// </summary>
+    public static void ThrowIfAnyNull<T>(IEnumerable<T> sequence) {
+      foreach (T t in sequence) {
+        if (t == null) {
+          throw new ArgumentNullException();
+        }
+      }
+    }
+  }
+}