Merge pull request #846 from jskeet/tostring

Support ToString in RepeatedField and MapField.

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);

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());
+        }
     }
 }

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)
         {

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>>
     {
@@ -464,6 +469,17 @@ namespace Google.Protobuf.Collections
             array[count] = default(T);
         }
 
+        /// <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>