Merge pull request #846 from jskeet/tostring

Support ToString in RepeatedField and MapField.

5 files changed, 203 insertions, 115 deletions

diff --git a/csharp/src/Google.Protobuf.Test/Collections/MapFieldTest.cs b/csharp/src/Google.Protobuf.Test/Collections/MapFieldTest.cs
index 29c4c2a9..ba82c0e8 100644
--- a/csharp/src/Google.Protobuf.Test/Collections/MapFieldTest.cs
+++ b/csharp/src/Google.Protobuf.Test/Collections/MapFieldTest.cs
@@ -562,6 +562,20 @@ namespace Google.Protobuf.Collections
             Assert.IsFalse(values.Contains(null));
         }
 
+        [Test]
+        public void ToString_StringToString()
+        {
+            var map = new MapField<string, string> { { "foo", "bar" }, { "x", "y" } };
+            Assert.AreEqual("{ \"foo\": \"bar\", \"x\": \"y\" }", map.ToString());
+        }
+
+        [Test]
+        public void ToString_UnsupportedKeyType()
+        {
+            var map = new MapField<byte, string> { { 10, "foo" } };
+            Assert.Throws<ArgumentException>(() => map.ToString());
+        }
+
         private static KeyValuePair<TKey, TValue> NewKeyValuePair<TKey, TValue>(TKey key, TValue value)
         {
             return new KeyValuePair<TKey, TValue>(key, value);
diff --git a/csharp/src/Google.Protobuf.Test/Collections/RepeatedFieldTest.cs b/csharp/src/Google.Protobuf.Test/Collections/RepeatedFieldTest.cs
index 8c804fdd..8ed54cfb 100644
--- a/csharp/src/Google.Protobuf.Test/Collections/RepeatedFieldTest.cs
+++ b/csharp/src/Google.Protobuf.Test/Collections/RepeatedFieldTest.cs
@@ -37,6 +37,7 @@ using System.IO;
 using System.Linq;
 using System.Text;
 using Google.Protobuf.TestProtos;
+using Google.Protobuf.WellKnownTypes;
 using NUnit.Framework;
 
 namespace Google.Protobuf.Collections
@@ -599,5 +600,61 @@ namespace Google.Protobuf.Collections
             list.Insert(1, "middle");
             CollectionAssert.AreEqual(new[] { "first", "middle", "second" }, list);
         }
+
+        [Test]
+        public void ToString_Integers()
+        {
+            var list = new RepeatedField<int> { 5, 10, 20 };
+            var text = list.ToString();
+            Assert.AreEqual("[ 5, 10, 20 ]", text);
+        }
+
+        [Test]
+        public void ToString_Strings()
+        {
+            var list = new RepeatedField<string> { "x", "y", "z" };
+            var text = list.ToString();
+            Assert.AreEqual("[ \"x\", \"y\", \"z\" ]", text);
+        }
+
+        [Test]
+        public void ToString_Messages()
+        {
+            var list = new RepeatedField<TestAllTypes> { new TestAllTypes { SingleDouble = 1.5 }, new TestAllTypes { SingleInt32 = 10 } };
+            var text = list.ToString();
+            Assert.AreEqual("[ { \"singleDouble\": 1.5 }, { \"singleInt32\": 10 } ]", text);
+        }
+
+        [Test]
+        public void ToString_Empty()
+        {
+            var list = new RepeatedField<TestAllTypes> { };
+            var text = list.ToString();
+            Assert.AreEqual("[ ]", text);
+        }
+
+        [Test]
+        public void ToString_InvalidElementType()
+        {
+            var list = new RepeatedField<decimal> { 15m };
+            Assert.Throws<ArgumentException>(() => list.ToString());
+        }
+
+        [Test]
+        public void ToString_Timestamp()
+        {
+            var list = new RepeatedField<Timestamp> { Timestamp.FromDateTime(new DateTime(2015, 10, 1, 12, 34, 56, DateTimeKind.Utc)) };
+            var text = list.ToString();
+            Assert.AreEqual("[ \"2015-10-01T12:34:56Z\" ]", text);
+        }
+
+        [Test]
+        public void ToString_Struct()
+        {
+            var message = new Struct { Fields = { { "foo", new Value { NumberValue = 20 } } } };
+            var list = new RepeatedField<Struct> { message };
+            var text = list.ToString();
+            Assert.AreEqual(text, "[ { \"foo\": 20 } ]", message.ToString());
+        }
     }
 }
diff --git a/csharp/src/Google.Protobuf/Collections/MapField.cs b/csharp/src/Google.Protobuf/Collections/MapField.cs
index 0fa63bef..c0ed28ae 100644
--- a/csharp/src/Google.Protobuf/Collections/MapField.cs
+++ b/csharp/src/Google.Protobuf/Collections/MapField.cs
@@ -35,6 +35,7 @@ using System;
 using System.Collections;
 using System.Collections.Generic;
 using System.Linq;
+using System.Text;
 using Google.Protobuf.Compatibility;
 
 namespace Google.Protobuf.Collections
@@ -45,10 +46,17 @@ namespace Google.Protobuf.Collections
     /// <typeparam name="TKey">Key type in the map. Must be a type supported by Protocol Buffer map keys.</typeparam>
     /// <typeparam name="TValue">Value type in the map. Must be a type supported by Protocol Buffers.</typeparam>
     /// <remarks>
+    /// <para>
     /// This implementation preserves insertion order for simplicity of testing
     /// code using maps fields. Overwriting an existing entry does not change the
     /// position of that entry within the map. Equality is not order-sensitive.
     /// For string keys, the equality comparison is provided by <see cref="StringComparer.Ordinal" />.
+    /// </para>
+    /// <para>
+    /// This implementation does not generally prohibit the use of key/value types which are not
+    /// supported by Protocol Buffers (e.g. using a key type of <code>byte</code>) but nor does it guarantee
+    /// that all operations will work in such cases.
+    /// </para>
     /// </remarks>
     public sealed class MapField<TKey, TValue> : IDeepCloneable<MapField<TKey, TValue>>, IDictionary<TKey, TValue>, IEquatable<MapField<TKey, TValue>>, IDictionary
     {
@@ -482,6 +490,17 @@ namespace Google.Protobuf.Collections
             return size;
         }
 
+        /// <summary>
+        /// Returns a string representation of this repeated field, in the same
+        /// way as it would be represented by the default JSON formatter.
+        /// </summary>
+        public override string ToString()
+        {
+            var builder = new StringBuilder();
+            JsonFormatter.Default.WriteDictionary(builder, this);
+            return builder.ToString();
+        }
+
         #region IDictionary explicit interface implementation
         void IDictionary.Add(object key, object value)
         {
diff --git a/csharp/src/Google.Protobuf/Collections/RepeatedField.cs b/csharp/src/Google.Protobuf/Collections/RepeatedField.cs
index d9ced6ec..e3f65afe 100644
--- a/csharp/src/Google.Protobuf/Collections/RepeatedField.cs
+++ b/csharp/src/Google.Protobuf/Collections/RepeatedField.cs
@@ -33,6 +33,7 @@
 using System;
 using System.Collections;
 using System.Collections.Generic;
+using System.Text;
 using Google.Protobuf.Compatibility;
 
 namespace Google.Protobuf.Collections
@@ -41,6 +42,10 @@ namespace Google.Protobuf.Collections
     /// The contents of a repeated field: essentially, a collection with some extra
     /// restrictions (no null values) and capabilities (deep cloning).
     /// </summary>
+    /// <remarks>
+    /// This implementation does not generally prohibit the use of types which are not
+    /// supported by Protocol Buffers but nor does it guarantee that all operations will work in such cases.
+    /// </remarks>
     /// <typeparam name="T">The element type of the repeated field.</typeparam>
     public sealed class RepeatedField<T> : IList<T>, IList, IDeepCloneable<RepeatedField<T>>, IEquatable<RepeatedField<T>>
     {
@@ -465,6 +470,17 @@ namespace Google.Protobuf.Collections
         }
 
         /// <summary>
+        /// Returns a string representation of this repeated field, in the same
+        /// way as it would be represented by the default JSON formatter.
+        /// </summary>
+        public override string ToString()
+        {
+            var builder = new StringBuilder();
+            JsonFormatter.Default.WriteList(builder, this);
+            return builder.ToString();
+        }
+
+        /// <summary>
         /// Gets or sets the item at the specified index.
         /// </summary>
         /// <value>
diff --git a/csharp/src/Google.Protobuf/JsonFormatter.cs b/csharp/src/Google.Protobuf/JsonFormatter.cs
index 12bbdfdd..3f9bd478 100644
--- a/csharp/src/Google.Protobuf/JsonFormatter.cs
+++ b/csharp/src/Google.Protobuf/JsonFormatter.cs
@@ -170,7 +170,7 @@ namespace Google.Protobuf
                     continue;
                 }
                 // Omit awkward (single) values such as unknown enum values
-                if (!field.IsRepeated && !field.IsMap && !CanWriteSingleValue(accessor.Descriptor, value))
+                if (!field.IsRepeated && !field.IsMap && !CanWriteSingleValue(value))
                 {
                     continue;
                 }
@@ -182,7 +182,7 @@ namespace Google.Protobuf
                 }
                 WriteString(builder, ToCamelCase(accessor.Descriptor.Name));
                 builder.Append(": ");
-                WriteValue(builder, accessor, value);
+                WriteValue(builder, value);
                 first = false;
             }            
             builder.Append(first ? "}" : " }");
@@ -291,93 +291,81 @@ namespace Google.Protobuf
                     throw new ArgumentException("Invalid field type");
             }
         }
-
-        private void WriteValue(StringBuilder builder, IFieldAccessor accessor, object value)
+        
+        private void WriteValue(StringBuilder builder, object value)
         {
-            if (accessor.Descriptor.IsMap)
+            if (value == null)
             {
-                WriteDictionary(builder, accessor, (IDictionary) value);
+                WriteNull(builder);
             }
-            else if (accessor.Descriptor.IsRepeated)
+            else if (value is bool)
             {
-                WriteList(builder, accessor, (IList) value);
+                builder.Append((bool) value ? "true" : "false");
             }
-            else
+            else if (value is ByteString)
             {
-                WriteSingleValue(builder, accessor.Descriptor, value);
+                // Nothing in Base64 needs escaping
+                builder.Append('"');
+                builder.Append(((ByteString) value).ToBase64());
+                builder.Append('"');
             }
-        }
-
-        private void WriteSingleValue(StringBuilder builder, FieldDescriptor descriptor, object value)
-        {
-            switch (descriptor.FieldType)
+            else if (value is string)
             {
-                case FieldType.Bool:
-                    builder.Append((bool) value ? "true" : "false");
-                    break;
-                case FieldType.Bytes:
-                    // Nothing in Base64 needs escaping
+                WriteString(builder, (string) value);
+            }
+            else if (value is IDictionary)
+            {
+                WriteDictionary(builder, (IDictionary) value);
+            }
+            else if (value is IList)
+            {
+                WriteList(builder, (IList) value);
+            }
+            else if (value is int || value is uint)
+            {
+                IFormattable formattable = (IFormattable) value;
+                builder.Append(formattable.ToString("d", CultureInfo.InvariantCulture));
+            }
+            else if (value is long || value is ulong)
+            {
+                builder.Append('"');
+                IFormattable formattable = (IFormattable) value;
+                builder.Append(formattable.ToString("d", CultureInfo.InvariantCulture));
+                builder.Append('"');
+            }
+            else if (value is System.Enum)
+            {
+                WriteString(builder, value.ToString());
+            }
+            else if (value is float || value is double)
+            {
+                string text = ((IFormattable) value).ToString("r", CultureInfo.InvariantCulture);
+                if (text == "NaN" || text == "Infinity" || text == "-Infinity")
+                {
                     builder.Append('"');
-                    builder.Append(((ByteString) value).ToBase64());
+                    builder.Append(text);
                     builder.Append('"');
-                    break;
-                case FieldType.String:
-                    WriteString(builder, (string) value);
-                    break;
-                case FieldType.Fixed32:
-                case FieldType.UInt32:
-                case FieldType.SInt32:
-                case FieldType.Int32:
-                case FieldType.SFixed32:
-                    {
-                        IFormattable formattable = (IFormattable) value;
-                        builder.Append(formattable.ToString("d", CultureInfo.InvariantCulture));
-                        break;
-                    }
-                case FieldType.Enum:
-                    EnumValueDescriptor enumValue = descriptor.EnumType.FindValueByNumber((int) value);
-                    // We will already have validated that this is a known value.
-                    WriteString(builder, enumValue.Name);
-                    break;
-                case FieldType.Fixed64:
-                case FieldType.UInt64:
-                case FieldType.SFixed64:
-                case FieldType.Int64:
-                case FieldType.SInt64:
-                    {
-                        builder.Append('"');
-                        IFormattable formattable = (IFormattable) value;
-                        builder.Append(formattable.ToString("d", CultureInfo.InvariantCulture));
-                        builder.Append('"');
-                        break;
-                    }
-                case FieldType.Double:
-                case FieldType.Float:
-                    string text = ((IFormattable) value).ToString("r", CultureInfo.InvariantCulture);
-                    if (text == "NaN" || text == "Infinity" || text == "-Infinity")
-                    {
-                        builder.Append('"');
-                        builder.Append(text);
-                        builder.Append('"');
-                    }
-                    else
-                    {
-                        builder.Append(text);
-                    }
-                    break;
-                case FieldType.Message:
-                case FieldType.Group: // Never expect to get this, but...
-                    if (descriptor.MessageType.IsWellKnownType)
-                    {
-                        WriteWellKnownTypeValue(builder, descriptor.MessageType, value, true);
-                    }
-                    else
-                    {
-                        WriteMessage(builder, (IMessage) value);
-                    }
-                    break;
-                default:
-                    throw new ArgumentException("Invalid field type: " + descriptor.FieldType);
+                }
+                else
+                {
+                    builder.Append(text);
+                }
+            }
+            else if (value is IMessage)
+            {
+                IMessage message = (IMessage) value;
+                if (message.Descriptor.IsWellKnownType)
+                {
+                    WriteWellKnownTypeValue(builder, message.Descriptor, value, true);
+                }
+                else
+                {
+                    WriteMessage(builder, (IMessage) value);
+                }
+            }
+            else
+            {
+                throw new ArgumentException("Unable to format value of type " + value.GetType());
             }
         }
 
@@ -398,7 +386,7 @@ namespace Google.Protobuf
             // so we can write it as if we were unconditionally writing the Value field for the wrapper type.
             if (descriptor.File == Int32Value.Descriptor.File)
             {
-                WriteSingleValue(builder, descriptor.FindFieldByNumber(1), value);
+                WriteValue(builder, value);
                 return;
             }
             if (descriptor.FullName == Timestamp.Descriptor.FullName)
@@ -424,7 +412,7 @@ namespace Google.Protobuf
             if (descriptor.FullName == ListValue.Descriptor.FullName)
             {
                 var fieldAccessor = descriptor.Fields[ListValue.ValuesFieldNumber].Accessor;
-                WriteList(builder, fieldAccessor, (IList) fieldAccessor.GetValue((IMessage) value));
+                WriteList(builder, (IList) fieldAccessor.GetValue((IMessage) value));
                 return;
             }
             if (descriptor.FullName == Value.Descriptor.FullName)
@@ -565,7 +553,7 @@ namespace Google.Protobuf
                 case Value.BoolValueFieldNumber:
                 case Value.StringValueFieldNumber:
                 case Value.NumberValueFieldNumber:
-                    WriteSingleValue(builder, specifiedField, value);
+                    WriteValue(builder, value);
                     return;
                 case Value.StructValueFieldNumber:
                 case Value.ListValueFieldNumber:
@@ -581,13 +569,13 @@ namespace Google.Protobuf
             }
         }
 
-        private void WriteList(StringBuilder builder, IFieldAccessor accessor, IList list)
+        internal void WriteList(StringBuilder builder, IList list)
         {
             builder.Append("[ ");
             bool first = true;
             foreach (var value in list)
             {
-                if (!CanWriteSingleValue(accessor.Descriptor, value))
+                if (!CanWriteSingleValue(value))
                 {
                     continue;
                 }
@@ -595,22 +583,20 @@ namespace Google.Protobuf
                 {
                     builder.Append(", ");
                 }
-                WriteSingleValue(builder, accessor.Descriptor, value);
+                WriteValue(builder, value);
                 first = false;
             }
             builder.Append(first ? "]" : " ]");
         }
 
-        private void WriteDictionary(StringBuilder builder, IFieldAccessor accessor, IDictionary dictionary)
+        internal void WriteDictionary(StringBuilder builder, IDictionary dictionary)
         {
             builder.Append("{ ");
             bool first = true;
-            FieldDescriptor keyType = accessor.Descriptor.MessageType.FindFieldByNumber(1);
-            FieldDescriptor valueType = accessor.Descriptor.MessageType.FindFieldByNumber(2);
             // This will box each pair. Could use IDictionaryEnumerator, but that's ugly in terms of disposal.
             foreach (DictionaryEntry pair in dictionary)
             {
-                if (!CanWriteSingleValue(valueType, pair.Value))
+                if (!CanWriteSingleValue(pair.Value))
                 {
                     continue;
                 }
@@ -619,32 +605,29 @@ namespace Google.Protobuf
                     builder.Append(", ");
                 }
                 string keyText;
-                switch (keyType.FieldType)
+                if (pair.Key is string)
                 {
-                    case FieldType.String:
-                        keyText = (string) pair.Key;
-                        break;
-                    case FieldType.Bool:
-                        keyText = (bool) pair.Key ? "true" : "false";
-                        break;
-                    case FieldType.Fixed32:
-                    case FieldType.Fixed64:
-                    case FieldType.SFixed32:
-                    case FieldType.SFixed64:
-                    case FieldType.Int32:
-                    case FieldType.Int64:
-                    case FieldType.SInt32:
-                    case FieldType.SInt64:
-                    case FieldType.UInt32:
-                    case FieldType.UInt64:
-                        keyText = ((IFormattable) pair.Key).ToString("d", CultureInfo.InvariantCulture);
-                        break;
-                    default:
-                        throw new ArgumentException("Invalid key type: " + keyType.FieldType);
+                    keyText = (string) pair.Key;
+                }
+                else if (pair.Key is bool)
+                {
+                    keyText = (bool) pair.Key ? "true" : "false";
+                }
+                else if (pair.Key is int || pair.Key is uint | pair.Key is long || pair.Key is ulong)
+                {
+                    keyText = ((IFormattable) pair.Key).ToString("d", CultureInfo.InvariantCulture);
+                }
+                else
+                {
+                    if (pair.Key == null)
+                    {
+                        throw new ArgumentException("Dictionary has entry with null key");
+                    }
+                    throw new ArgumentException("Unhandled dictionary key type: " + pair.Key.GetType());
                 }
                 WriteString(builder, keyText);
                 builder.Append(": ");
-                WriteSingleValue(builder, valueType, pair.Value);
+                WriteValue(builder, pair.Value);
                 first = false;
             }
             builder.Append(first ? "}" : " }");
@@ -655,12 +638,11 @@ namespace Google.Protobuf
         /// Currently only relevant for enums, where unknown values can't be represented.
         /// For repeated/map fields, this always returns true.
         /// </summary>
-        private bool CanWriteSingleValue(FieldDescriptor descriptor, object value)
+        private bool CanWriteSingleValue(object value)
         {
-            if (descriptor.FieldType == FieldType.Enum)
+            if (value is System.Enum)
             {
-                EnumValueDescriptor enumValue = descriptor.EnumType.FindValueByNumber((int) value);
-                return enumValue != null;
+                return System.Enum.IsDefined(value.GetType(), value);
             }
             return true;
         }