Move ConvertTo tests to SS.Text + handle empty string to ValueType

Author: mythz

src/ServiceStack.Text/AutoMappingUtils.cs

@@ -160,38 +160,46 @@ public static object ConvertTo(this object from, Type toType, bool skipConverter
 
         public static object ChangeValueType(object from, Type toType)
         {
+            var s = from as string;
+            
             var fromType = from.GetType();
             if (!fromType.IsEnum && !toType.IsEnum)
             {
-                if (toType == typeof(char) && from is string s)
+                var toString = toType == typeof(string);
+                if (toType == typeof(char) && s != null)
                     return s.Length > 0 ? (object) s[0] : null;
-                if (toType == typeof(string) && from is char c)
+                if (toString && from is char c)
                     return c.ToString();
                 if (toType == typeof(TimeSpan) && from is long ticks)
                     return new TimeSpan(ticks);
                 if (toType == typeof(long) && from is TimeSpan time)
                     return time.Ticks;
 
                 var destNumberType = DynamicNumber.GetNumber(toType);
-                var value = destNumberType?.ConvertFrom(from);
-                if (value != null)
+                if (destNumberType != null)
                 {
-                    if (toType == typeof(char))
-                        return value.ToString()[0];
-
-                    return value;
+                    if (s != null && s == string.Empty)
+                        return destNumberType.DefaultValue;
+                    
+                    var value = destNumberType.ConvertFrom(from);
+                    if (value != null)
+                    {
+                        return toType == typeof(char) 
+                            ? value.ToString()[0] 
+                            : value;
+                    }
                 }
 
-                if (toType == typeof(string))
+                if (toString)
                 {
                     var srcNumberType = DynamicNumber.GetNumber(from.GetType());
                     if (srcNumberType != null)
-                        return srcNumberType.ToString(@from);
+                        return srcNumberType.ToString(from);
                 }
             }
 
-            if (from is string strValue)
-                return TypeSerializer.DeserializeFromString(strValue, toType);
+            if (s != null)
+                return TypeSerializer.DeserializeFromString(s, toType);
 
             if (toType == typeof(string))
                 return from.ToJsv();

src/ServiceStack.Text/DynamicNumber.cs

@@ -13,6 +13,7 @@ public interface IDynamicNumber
         object ConvertFrom(object value);
         bool TryParse(string str, out object result);
         string ToString(object value);
+        object DefaultValue { get; }
 
         object add(object lhs, object rhs);
         object sub(object lhs, object rhs);
@@ -53,6 +54,7 @@ public bool TryParse(string str, out object result)
         }
 
         public string ToString(object value) => Convert(value).ToString();
+        public object DefaultValue => default(sbyte);
 
         public object add(object lhs, object rhs) => Convert(lhs) + Convert(rhs);
         public object sub(object lhs, object rhs) => Convert(lhs) - Convert(rhs);
@@ -93,6 +95,7 @@ public bool TryParse(string str, out object result)
         }
 
         public string ToString(object value) => Convert(value).ToString();
+        public object DefaultValue => default(byte);
 
         public object add(object lhs, object rhs) => Convert(lhs) + Convert(rhs);
         public object sub(object lhs, object rhs) => Convert(lhs) - Convert(rhs);
@@ -133,6 +136,7 @@ public bool TryParse(string str, out object result)
         }
 
         public string ToString(object value) => Convert(value).ToString();
+        public object DefaultValue => default(short);
 
         public object add(object lhs, object rhs) => Convert(lhs) + Convert(rhs);
         public object sub(object lhs, object rhs) => Convert(lhs) - Convert(rhs);
@@ -173,6 +177,7 @@ public bool TryParse(string str, out object result)
         }
 
         public string ToString(object value) => Convert(value).ToString();
+        public object DefaultValue => default(ushort);
 
         public object add(object lhs, object rhs) => Convert(lhs) + Convert(rhs);
         public object sub(object lhs, object rhs) => Convert(lhs) - Convert(rhs);
@@ -213,6 +218,7 @@ public bool TryParse(string str, out object result)
         }
 
         public string ToString(object value) => Convert(value).ToString();
+        public object DefaultValue => default(int);
 
         public object add(object lhs, object rhs) => Convert(lhs) + Convert(rhs);
         public object sub(object lhs, object rhs) => Convert(lhs) - Convert(rhs);
@@ -253,6 +259,7 @@ public bool TryParse(string str, out object result)
         }
 
         public string ToString(object value) => Convert(value).ToString();
+        public object DefaultValue => default(uint);
 
         public object add(object lhs, object rhs) => Convert(lhs) + Convert(rhs);
         public object sub(object lhs, object rhs) => Convert(lhs) - Convert(rhs);
@@ -293,6 +300,7 @@ public bool TryParse(string str, out object result)
         }
 
         public string ToString(object value) => Convert(value).ToString();
+        public object DefaultValue => default(long);
 
         public object add(object lhs, object rhs) => Convert(lhs) + Convert(rhs);
         public object sub(object lhs, object rhs) => Convert(lhs) - Convert(rhs);
@@ -333,6 +341,7 @@ public bool TryParse(string str, out object result)
         }
 
         public string ToString(object value) => Convert(value).ToString();
+        public object DefaultValue => default(ulong);
 
         public object add(object lhs, object rhs) => Convert(lhs) + Convert(rhs);
         public object sub(object lhs, object rhs) => Convert(lhs) - Convert(rhs);
@@ -373,6 +382,7 @@ public bool TryParse(string str, out object result)
         }
 
         public string ToString(object value) => Convert(value).ToString("r", CultureInfo.InvariantCulture);
+        public object DefaultValue => default(float);
 
         public object add(object lhs, object rhs) => Convert(lhs) + Convert(rhs);
         public object sub(object lhs, object rhs) => Convert(lhs) - Convert(rhs);
@@ -413,6 +423,7 @@ public bool TryParse(string str, out object result)
         }
 
         public string ToString(object value) => Convert(value).ToString("r", CultureInfo.InvariantCulture);
+        public object DefaultValue => default(double);
 
         public object add(object lhs, object rhs) => Convert(lhs) + Convert(rhs);
         public object sub(object lhs, object rhs) => Convert(lhs) - Convert(rhs);
@@ -453,6 +464,7 @@ public bool TryParse(string str, out object result)
         }
 
         public string ToString(object value) => Convert(value).ToString(CultureInfo.InvariantCulture);
+        public object DefaultValue => default(decimal);
 
         public object add(object lhs, object rhs) => Convert(lhs) + Convert(rhs);
         public object sub(object lhs, object rhs) => Convert(lhs) - Convert(rhs);

tests/ServiceStack.Text.Tests/AutoMappingTests.cs

@@ -1076,5 +1076,27 @@ public void Can_convert_to_array_to_string()
             Assert.That(new []{ new ViewModel { Public = "A"} }.ConvertTo<string>(), Is.Not.Empty);
             Assert.That(new []{ DayOfWeek.Monday }.ConvertTo<string>(), Is.Not.Empty);
         }
+        
+        [Test]
+        public void To_works_with_ValueTypes()
+        {
+            Assert.That(1.ToString().ConvertTo<int>(), Is.EqualTo(1));
+        }
+
+        [Test]
+        public void To_on_null_or_empty_string_returns_default_value_supplied()
+        {
+            const string nullString = null;
+            Assert.That("".ConvertTo(1), Is.EqualTo(1));
+            Assert.That("".ConvertTo(default(int)), Is.EqualTo(default(int)));
+            Assert.That(nullString.ConvertTo(1), Is.EqualTo(1));
+        }
+
+        [Test]
+        public void To_ValueType_on_null_or_empty_string_returns_default_value()
+        {
+            Assert.That("".ConvertTo<int>(), Is.EqualTo(default(int)));
+        }
+
     }
 }