[EN .NET] Workaround for TimexProperty.ToString() to not crash on DateTimeRanges (#2894)

* Workaround for TimexProperty.ToString() to not crash on DateTimeRanges 

* Add TODO for fixing the TimexProperty date range representation properly according to review

Author: shana

.NET/Microsoft.Recognizers.Text.DataTypes.DataDrivenTests/TestTimex.cs

@@ -138,6 +138,14 @@ public void DataTypes_Timex_FromDateTime_ToString()
             Assert.AreEqual("13th March 2022", timex.ToString());
         }
 
+        [TestMethod]
+        public void DataTypes_Timex_FromDateTimeRange_ToString()
+        {
+            // TODO: This test documents a workaround to avoid exceptions when calling TimexProperty.ToString(). Proper fix for date range representation is needed.
+            var timex = new TimexProperty("(2022-03-15T16,2022-03-15T18,PT2H)");
+            Assert.AreEqual("15th March 2022 4PM", timex.ToString());
+        }
+
         private static void Roundtrip(string timex)
         {
             Assert.AreEqual(timex, new TimexProperty(timex).TimexValue);

.NET/Microsoft.Recognizers.Text.DataTypes.TimexExpression/English/TimexConvertEnglish.cs

@@ -2,6 +2,7 @@
 // Licensed under the MIT License.
 
 using System;
+using System.Collections.Generic;
 using System.Globalization;
 
 namespace Microsoft.Recognizers.Text.DataTypes.TimexExpression
@@ -216,9 +217,27 @@ private static string ConvertDateTime(TimexProperty timex)
 
         private static string ConvertDateTimeRange(TimexProperty timex)
         {
-            if (timex.Types.Contains(Constants.TimexTypes.TimeRange))
+            var parts = new List<string>();
+
+            var types = timex.Types;
+            if (types.Contains(Constants.TimexTypes.Date))
+            {
+                parts.Add(ConvertDate(timex));
+            }
+
+            if (types.Contains(Constants.TimexTypes.Time))
+            {
+                parts.Add(ConvertTime(timex));
+            }
+
+            if (timex.PartOfDay is not null)
+            {
+                parts.Add(ConvertTimeRange(timex));
+            }
+
+            if (parts.Count > 0)
             {
-                return $"{ConvertDate(timex)} {ConvertTimeRange(timex)}";
+                return string.Join(" ", parts);
             }
 
             // date + time + duration