Use the new JsonFormatter to implement ToString on generated messages.

csharp/src/AddressBook/Addressbook.cs

@@ -160,6 +160,10 @@ namespace Google.Protobuf.Examples.AddressBook {
       return hash;
     }
 
+    public override string ToString() {
+      return pb::JsonFormatter.Default.Format(this);
+    }
+
     public void WriteTo(pb::CodedOutputStream output) {
       if (Name.Length != 0) {
         output.WriteRawTag(10);
@@ -330,6 +334,10 @@ namespace Google.Protobuf.Examples.AddressBook {
           return hash;
         }
 
+        public override string ToString() {
+          return pb::JsonFormatter.Default.Format(this);
+        }
+
         public void WriteTo(pb::CodedOutputStream output) {
           if (Number.Length != 0) {
             output.WriteRawTag(10);
@@ -463,6 +471,10 @@ namespace Google.Protobuf.Examples.AddressBook {
       return hash;
     }
 
+    public override string ToString() {
+      return pb::JsonFormatter.Default.Format(this);
+    }
+
     public void WriteTo(pb::CodedOutputStream output) {
       person_.WriteTo(output, _repeated_person_codec);
     }

csharp/src/ProtocolBuffers.Test/TestProtos/UnittestImportProto3.cs

@@ -124,6 +124,10 @@ namespace Google.Protobuf.TestProtos {
       return hash;
     }
 
+    public override string ToString() {
+      return pb::JsonFormatter.Default.Format(this);
+    }
+
     public void WriteTo(pb::CodedOutputStream output) {
       if (D != 0) {
         output.WriteRawTag(8);

csharp/src/ProtocolBuffers.Test/TestProtos/UnittestImportPublicProto3.cs

@@ -109,6 +109,10 @@ namespace Google.Protobuf.TestProtos {
       return hash;
     }
 
+    public override string ToString() {
+      return pb::JsonFormatter.Default.Format(this);
+    }
+
     public void WriteTo(pb::CodedOutputStream output) {
       if (E != 0) {
         output.WriteRawTag(8);

csharp/src/ProtocolBuffers.Test/TestProtos/UnittestIssues.cs

@@ -148,6 +148,10 @@ namespace UnitTest.Issues.TestProtos {
       return hash;
     }
 
+    public override string ToString() {
+      return pb::JsonFormatter.Default.Format(this);
+    }
+
     public void WriteTo(pb::CodedOutputStream output) {
     }
 
@@ -237,6 +241,10 @@ namespace UnitTest.Issues.TestProtos {
           return hash;
         }
 
+        public override string ToString() {
+          return pb::JsonFormatter.Default.Format(this);
+        }
+
         public void WriteTo(pb::CodedOutputStream output) {
         }
 
@@ -326,6 +334,10 @@ namespace UnitTest.Issues.TestProtos {
               return hash;
             }
 
+            public override string ToString() {
+              return pb::JsonFormatter.Default.Format(this);
+            }
+
             public void WriteTo(pb::CodedOutputStream output) {
             }
 
@@ -459,6 +471,10 @@ namespace UnitTest.Issues.TestProtos {
       return hash;
     }
 
+    public override string ToString() {
+      return pb::JsonFormatter.Default.Format(this);
+    }
+
     public void WriteTo(pb::CodedOutputStream output) {
       if (Value != global::UnitTest.Issues.TestProtos.NegativeEnum.NEGATIVE_ENUM_ZERO) {
         output.WriteRawTag(8);
@@ -577,6 +593,10 @@ namespace UnitTest.Issues.TestProtos {
       return hash;
     }
 
+    public override string ToString() {
+      return pb::JsonFormatter.Default.Format(this);
+    }
+
     public void WriteTo(pb::CodedOutputStream output) {
     }
 
@@ -746,6 +766,10 @@ namespace UnitTest.Issues.TestProtos {
       return hash;
     }
 
+    public override string ToString() {
+      return pb::JsonFormatter.Default.Format(this);
+    }
+
     public void WriteTo(pb::CodedOutputStream output) {
       if (PrimitiveValue != 0) {
         output.WriteRawTag(8);
@@ -918,6 +942,10 @@ namespace UnitTest.Issues.TestProtos {
       return hash;
     }
 
+    public override string ToString() {
+      return pb::JsonFormatter.Default.Format(this);
+    }
+
     public void WriteTo(pb::CodedOutputStream output) {
       if (Item != 0) {
         output.WriteRawTag(8);

csharp/src/ProtocolBuffers/DescriptorProtos/DescriptorProtoFile.cs

@@ -299,6 +299,10 @@ namespace Google.Protobuf.DescriptorProtos {
       return hash;
     }
 
+    public override string ToString() {
+      return pb::JsonFormatter.Default.Format(this);
+    }
+
     public void WriteTo(pb::CodedOutputStream output) {
       file_.WriteTo(output, _repeated_file_codec);
     }
@@ -545,6 +549,10 @@ namespace Google.Protobuf.DescriptorProtos {
       return hash;
     }
 
+    public override string ToString() {
+      return pb::JsonFormatter.Default.Format(this);
+    }
+
     public void WriteTo(pb::CodedOutputStream output) {
       if (Name.Length != 0) {
         output.WriteRawTag(10);
@@ -889,6 +897,10 @@ namespace Google.Protobuf.DescriptorProtos {
       return hash;
     }
 
+    public override string ToString() {
+      return pb::JsonFormatter.Default.Format(this);
+    }
+
     public void WriteTo(pb::CodedOutputStream output) {
       if (Name.Length != 0) {
         output.WriteRawTag(10);
@@ -1094,6 +1106,10 @@ namespace Google.Protobuf.DescriptorProtos {
           return hash;
         }
 
+        public override string ToString() {
+          return pb::JsonFormatter.Default.Format(this);
+        }
+
         public void WriteTo(pb::CodedOutputStream output) {
           if (Start != 0) {
             output.WriteRawTag(8);
@@ -1236,6 +1252,10 @@ namespace Google.Protobuf.DescriptorProtos {
           return hash;
         }
 
+        public override string ToString() {
+          return pb::JsonFormatter.Default.Format(this);
+        }
+
         public void WriteTo(pb::CodedOutputStream output) {
           if (Start != 0) {
             output.WriteRawTag(8);
@@ -1475,6 +1495,10 @@ namespace Google.Protobuf.DescriptorProtos {
       return hash;
     }
 
+    public override string ToString() {
+      return pb::JsonFormatter.Default.Format(this);
+    }
+
     public void WriteTo(pb::CodedOutputStream output) {
       if (Name.Length != 0) {
         output.WriteRawTag(10);
@@ -1741,6 +1765,10 @@ namespace Google.Protobuf.DescriptorProtos {
       return hash;
     }
 
+    public override string ToString() {
+      return pb::JsonFormatter.Default.Format(this);
+    }
+
     public void WriteTo(pb::CodedOutputStream output) {
       if (Name.Length != 0) {
         output.WriteRawTag(10);
@@ -1882,6 +1910,10 @@ namespace Google.Protobuf.DescriptorProtos {
       return hash;
     }
 
+    public override string ToString() {
+      return pb::JsonFormatter.Default.Format(this);
+    }
+
     public void WriteTo(pb::CodedOutputStream output) {
       if (Name.Length != 0) {
         output.WriteRawTag(10);
@@ -2051,6 +2083,10 @@ namespace Google.Protobuf.DescriptorProtos {
       return hash;
     }
 
+    public override string ToString() {
+      return pb::JsonFormatter.Default.Format(this);
+    }
+
     public void WriteTo(pb::CodedOutputStream output) {
       if (Name.Length != 0) {
         output.WriteRawTag(10);
@@ -2226,6 +2262,10 @@ namespace Google.Protobuf.DescriptorProtos {
       return hash;
     }
 
+    public override string ToString() {
+      return pb::JsonFormatter.Default.Format(this);
+    }
+
     public void WriteTo(pb::CodedOutputStream output) {
       if (Name.Length != 0) {
         output.WriteRawTag(10);
@@ -2434,6 +2474,10 @@ namespace Google.Protobuf.DescriptorProtos {
       return hash;
     }
 
+    public override string ToString() {
+      return pb::JsonFormatter.Default.Format(this);
+    }
+
     public void WriteTo(pb::CodedOutputStream output) {
       if (Name.Length != 0) {
         output.WriteRawTag(10);
@@ -2806,6 +2850,10 @@ namespace Google.Protobuf.DescriptorProtos {
       return hash;
     }
 
+    public override string ToString() {
+      return pb::JsonFormatter.Default.Format(this);
+    }
+
     public void WriteTo(pb::CodedOutputStream output) {
       if (JavaPackage.Length != 0) {
         output.WriteRawTag(10);
@@ -3173,6 +3221,10 @@ namespace Google.Protobuf.DescriptorProtos {
       return hash;
     }
 
+    public override string ToString() {
+      return pb::JsonFormatter.Default.Format(this);
+    }
+
     public void WriteTo(pb::CodedOutputStream output) {
       if (MessageSetWireFormat != false) {
         output.WriteRawTag(8);
@@ -3414,6 +3466,10 @@ namespace Google.Protobuf.DescriptorProtos {
       return hash;
     }
 
+    public override string ToString() {
+      return pb::JsonFormatter.Default.Format(this);
+    }
+
     public void WriteTo(pb::CodedOutputStream output) {
       if (Ctype != global::Google.Protobuf.DescriptorProtos.FieldOptions.Types.CType.STRING) {
         output.WriteRawTag(8);
@@ -3649,6 +3705,10 @@ namespace Google.Protobuf.DescriptorProtos {
       return hash;
     }
 
+    public override string ToString() {
+      return pb::JsonFormatter.Default.Format(this);
+    }
+
     public void WriteTo(pb::CodedOutputStream output) {
       if (AllowAlias != false) {
         output.WriteRawTag(16);
@@ -3797,6 +3857,10 @@ namespace Google.Protobuf.DescriptorProtos {
       return hash;
     }
 
+    public override string ToString() {
+      return pb::JsonFormatter.Default.Format(this);
+    }
+
     public void WriteTo(pb::CodedOutputStream output) {
       if (Deprecated != false) {
         output.WriteRawTag(8);
@@ -3931,6 +3995,10 @@ namespace Google.Protobuf.DescriptorProtos {
       return hash;
     }
 
+    public override string ToString() {
+      return pb::JsonFormatter.Default.Format(this);
+    }
+
     public void WriteTo(pb::CodedOutputStream output) {
       if (Deprecated != false) {
         output.WriteRawTag(136, 2);
@@ -4065,6 +4133,10 @@ namespace Google.Protobuf.DescriptorProtos {
       return hash;
     }
 
+    public override string ToString() {
+      return pb::JsonFormatter.Default.Format(this);
+    }
+
     public void WriteTo(pb::CodedOutputStream output) {
       if (Deprecated != false) {
         output.WriteRawTag(136, 2);
@@ -4264,6 +4336,10 @@ namespace Google.Protobuf.DescriptorProtos {
       return hash;
     }
 
+    public override string ToString() {
+      return pb::JsonFormatter.Default.Format(this);
+    }
+
     public void WriteTo(pb::CodedOutputStream output) {
       name_.WriteTo(output, _repeated_name_codec);
       if (IdentifierValue.Length != 0) {
@@ -4470,6 +4546,10 @@ namespace Google.Protobuf.DescriptorProtos {
           return hash;
         }
 
+        public override string ToString() {
+          return pb::JsonFormatter.Default.Format(this);
+        }
+
         public void WriteTo(pb::CodedOutputStream output) {
           if (NamePart_.Length != 0) {
             output.WriteRawTag(10);
@@ -4603,6 +4683,10 @@ namespace Google.Protobuf.DescriptorProtos {
       return hash;
     }
 
+    public override string ToString() {
+      return pb::JsonFormatter.Default.Format(this);
+    }
+
     public void WriteTo(pb::CodedOutputStream output) {
       location_.WriteTo(output, _repeated_location_codec);
     }
@@ -4761,6 +4845,10 @@ namespace Google.Protobuf.DescriptorProtos {
           return hash;
         }
 
+        public override string ToString() {
+          return pb::JsonFormatter.Default.Format(this);
+        }
+
         public void WriteTo(pb::CodedOutputStream output) {
           path_.WriteTo(output, _repeated_path_codec);
           span_.WriteTo(output, _repeated_span_codec);

src/google/protobuf/compiler/csharp/csharp_field_base.h

@@ -58,6 +58,7 @@ class FieldGeneratorBase : public SourceGeneratorBase {
 
   virtual void WriteHash(io::Printer* printer) = 0;
   virtual void WriteEquals(io::Printer* printer) = 0;
+  // Currently unused, as we use reflection to generate JSON
   virtual void WriteToString(io::Printer* printer) = 0;
 
  protected:

src/google/protobuf/compiler/csharp/csharp_map_field.cc

@@ -117,12 +117,9 @@ void MapFieldGenerator::WriteEquals(io::Printer* printer) {
     variables_,
     "if (!$property_name$.Equals(other.$property_name$)) return false;\n");
 }
+
 void MapFieldGenerator::WriteToString(io::Printer* printer) {
-    /*
-  variables_["field_name"] = GetFieldName(descriptor_);
-  printer->Print(
-    variables_,
-    "PrintField(\"$field_name$\", has$property_name$, $name$_, writer);\n");*/
+    // TODO: If we ever actually use ToString, we'll need to impleme this...
 }
 
 void MapFieldGenerator::GenerateCloningCode(io::Printer* printer) {

src/google/protobuf/compiler/csharp/csharp_message.cc

@@ -429,7 +429,10 @@ void MessageGenerator::GenerateFrameworkMethods(io::Printer* printer) {
     printer->Outdent();
     printer->Print("}\n\n");
 
-    // TODO(jonskeet): ToString.
+    printer->Print(
+        "public override string ToString() {\n"
+        "  return pb::JsonFormatter.Default.Format(this);\n"
+        "}\n\n");
 }
 
 void MessageGenerator::GenerateMessageSerializationMethods(io::Printer* printer) {