updated the LUIS TryFindEntity extension to only return an entity by …

…… (#4509)

* updated the LUIS TryFindEntity extension to only return an entity by type if its start index doesn't overlap with the start and end index of other LuisResult Entities.  I came across this issue when working with an intent that accepts both a date and number.  If the intent message is 'make a reservation tomorrow morning at 2 for 7 people', 7 being the trained 'number' in LUIS, the current TryFindEntity extension was pulling back '2', which was already considered part of the datetime entity

* added unit tests and correctet and updated logic to only consider an overlap if start and end index are within another entity recommendation

CSharp/Library/Microsoft.Bot.Builder/Luis/Extensions.cs

@@ -53,7 +53,16 @@ public static partial class Extensions
         /// <returns>True if the entity was found, false otherwise.</returns>
         public static bool TryFindEntity(this LuisResult result, string type, out EntityRecommendation entity)
         {
-            entity = result.Entities?.FirstOrDefault(e => e.Type == type);
+            Func<EntityRecommendation, IList<EntityRecommendation>, bool> doesNotOverlapRange = (current, recommendations) =>
+            {
+                return !recommendations.Where(r => current != r)
+                            .Any(r => r.StartIndex.HasValue && r.EndIndex.HasValue && current.StartIndex.HasValue && 
+                                 r.StartIndex.Value <= current.StartIndex.Value && r.EndIndex.Value >= current.EndIndex.Value);
+            };
+
+
+            // find the recommended entity that does not overlap start and end ranges with other result entities
+            entity = result.Entities?.Where(e => e.Type == type && doesNotOverlapRange(e, result.Entities)).FirstOrDefault();
             return entity != null;
         }
 

CSharp/Tests/Microsoft.Bot.Builder.Tests/LuisTryFindEntityTests.cs

@@ -0,0 +1,90 @@
+using Microsoft.Bot.Builder.Luis.Models;
+using System.Collections.Generic;
+using Microsoft.Bot.Builder.Luis;
+using Microsoft.VisualStudio.TestTools.UnitTesting;
+
+namespace Microsoft.Bot.Builder.Tests
+{
+    [TestClass]
+    public class LuisTryFindEntityTests
+    {
+
+        [TestMethod]
+        public void Luis_TryFindEntity_Date_And_Multiple_Numbers_Where_One_Number_Overlaps()
+        {
+            // assemble
+
+            var recommendations = new List<EntityRecommendation>
+            {
+                new EntityRecommendation { Type = "builtin.datetimeV2.time", Entity = "10 pm", StartIndex=25, EndIndex=30},
+                new EntityRecommendation { Type = "builtin.number", Entity = "10", StartIndex=25, EndIndex=27},
+                new EntityRecommendation { Type = "builtin.number", Entity = "8", StartIndex=35, EndIndex=36}
+            };
+
+            var result = new LuisResult("make me a reservation at 10 pm for 8 people", recommendations);
+
+            // act
+
+            EntityRecommendation recommendation;
+            result.TryFindEntity("builtin.number", out recommendation);
+
+            // assert
+
+            Assert.IsNotNull(recommendation,"entity recommendation not found");
+            Assert.AreEqual("8", recommendation.Entity, "wrong entity recommendation selected"); // it should not select 10 since that overlaps with the datetime entity
+        }
+
+        [TestMethod]
+        public void Luis_TryFindEntity_Date_And_One_Number_Where_One_Number_Overlaps()
+        {
+            // assemble
+
+            var recommendations = new List<EntityRecommendation>
+            {
+                new EntityRecommendation { Type = "builtin.number", Entity = "10", StartIndex=25, EndIndex=27}, // it should not consider this a number since if overlaps with the datetime entity
+                new EntityRecommendation { Type = "builtin.datetimeV2.time", Entity = "10 pm", StartIndex=25, EndIndex=30}
+            };
+
+            var result = new LuisResult("make me a reservation at 10 pm", recommendations);
+
+            // act
+
+            EntityRecommendation numberRecommendation;
+            result.TryFindEntity("builtin.number", out numberRecommendation);
+
+            EntityRecommendation timeRecommendation;
+            result.TryFindEntity("builtin.datetimeV2.time", out timeRecommendation);
+
+
+            // assert
+
+            Assert.IsNotNull(timeRecommendation, "time entity recommendation not found");
+            Assert.IsNull(numberRecommendation, "number recommendation should be null as it falls within the datetime range");
+            Assert.AreEqual("10 pm", timeRecommendation.Entity, "wrong entity recommendation selected");
+        }
+
+        [TestMethod]
+        public void Luis_TryFindEntity_Find_Number_No_Overlaps()
+        {
+            // assemble
+
+            var recommendations = new List<EntityRecommendation>
+            {
+                new EntityRecommendation { Type = "builtin.number", Entity = "8", StartIndex=26, EndIndex=27},
+            };
+
+            var result = new LuisResult("make me a reservation for 8 people", recommendations);
+
+            // act
+
+            EntityRecommendation numberRecommendation;
+            result.TryFindEntity("builtin.number", out numberRecommendation);
+
+
+            // assert
+
+            Assert.IsNotNull(numberRecommendation, "number recommendation not found");
+            Assert.AreEqual("8", numberRecommendation.Entity, "wrong entity recommendation selected");
+        }
+    }
+}

CSharp/Tests/Microsoft.Bot.Builder.Tests/Microsoft.Bot.Builder.Tests.csproj

@@ -102,6 +102,7 @@
     <Compile Include="DialogTaskManagerTests.cs" />
     <Compile Include="DialogTaskTests.cs" />
     <Compile Include="DialogTestBase.cs" />
+    <Compile Include="LuisTryFindEntityTests.cs" />
     <Compile Include="FormTests.cs" />
     <Compile Include="OrderedContractResolver.cs" />
     <Compile Include="PromptRecognizerTests.cs" />