Fix: Date search doesn't match ranges properly (#4762)

* Fix to allow date time to be searched against a resource with a span and if included in the span that resource will be returned.

* Updated tests based on recent changes

* Updated test fixtures. Removed temporary comments.

* Updated test results to match new expectations. Simplified logic for this particular case and addressed pr comments.

* Fixed unit test after recent changes.

* Updated more tetst based on recent changes.

src/Microsoft.Health.Fhir.Core.UnitTests/Features/Search/DateTimeEqualityRewriterTests.cs

@@ -29,7 +29,7 @@ public void GivenStartAndEndExpressions_WhenRewritten_AnUpperBoundOnStartIsAdded
             Expression rewrittenExpression = inputExpression.AcceptVisitor(DateTimeEqualityRewriter.Instance);
 
             Assert.Equal(
-                "(And (FieldGreaterThanOrEqual DateTimeStart 2021-01-01T00:00:00.0000000) (FieldLessThanOrEqual DateTimeStart 2021-01-01T23:59:59.0000000) (FieldLessThanOrEqual DateTimeEnd 2021-01-01T23:59:59.0000000))",
+                "(And (FieldLessThanOrEqual DateTimeStart 2021-01-01T23:59:59.0000000) (FieldGreaterThanOrEqual DateTimeEnd 2021-01-01T00:00:00.0000000))",
                 rewrittenExpression.ToString());
         }
 
@@ -57,7 +57,7 @@ public void GivenStartAndEndExpressionsInReverseOrder_WhenRewritten_AnUpperBound
             Expression rewrittenExpression = inputExpression.AcceptVisitor(DateTimeEqualityRewriter.Instance);
 
             Assert.Equal(
-                "(And (FieldGreaterThanOrEqual DateTimeStart 2021-01-01T00:00:00.0000000) (FieldLessThanOrEqual DateTimeStart 2021-01-01T23:59:59.0000000) (FieldLessThanOrEqual DateTimeEnd 2021-01-01T23:59:59.0000000))",
+                "(And (FieldLessThanOrEqual DateTimeStart 2021-01-01T23:59:59.0000000) (FieldGreaterThanOrEqual DateTimeEnd 2021-01-01T00:00:00.0000000))",
                 rewrittenExpression.ToString());
         }
 
@@ -72,7 +72,7 @@ public void GivenStartAndEndExclusiveExpressions_WhenRewritten_AnUpperBoundOnSta
             Expression rewrittenExpression = inputExpression.AcceptVisitor(DateTimeEqualityRewriter.Instance);
 
             Assert.Equal(
-                "(And (FieldGreaterThan DateTimeStart 2021-01-01T00:00:00.0000000) (FieldLessThan DateTimeStart 2021-01-01T23:59:59.0000000) (FieldLessThan DateTimeEnd 2021-01-01T23:59:59.0000000))",
+                "(And (FieldLessThan DateTimeStart 2021-01-01T23:59:59.0000000) (FieldGreaterThan DateTimeEnd 2021-01-01T00:00:00.0000000))",
                 rewrittenExpression.ToString());
         }
 
@@ -115,7 +115,7 @@ public void GivenStartAndEndExpressionsAndAnUnrelatedExpression_WhenRewritten_An
             Expression rewrittenExpression = inputExpression.AcceptVisitor(DateTimeEqualityRewriter.Instance);
 
             Assert.Equal(
-                "(And (FieldGreaterThanOrEqual DateTimeStart 2021-01-01T00:00:00.0000000) (FieldLessThanOrEqual DateTimeStart 2021-01-01T23:59:59.0000000) (FieldLessThanOrEqual DateTimeEnd 2021-01-01T23:59:59.0000000) (FieldEqual Number 1))",
+                "(And (FieldLessThanOrEqual DateTimeStart 2021-01-01T23:59:59.0000000) (FieldGreaterThanOrEqual DateTimeEnd 2021-01-01T00:00:00.0000000) (FieldEqual Number 1))",
                 rewrittenExpression.ToString());
         }
 

src/Microsoft.Health.Fhir.Core/Features/Search/Expressions/DateTimeEqualityRewriter.cs

@@ -46,11 +46,8 @@ public override Expression VisitMultiary(MultiaryExpression expression, object c
                 {
                     case ({ } low, { } high):
                         EnsureAllocatedAndPopulated(ref newExpressions, expression.Expressions, i);
-
-                        newExpressions.Add(low);
-                        newExpressions.Add(new BinaryExpression(high.BinaryOperator, low.FieldName, high.ComponentIndex, high.Value));
-                        newExpressions.Add(high);
-
+                        newExpressions.Add(new BinaryExpression(high.BinaryOperator, low.FieldName, low.ComponentIndex, high.Value));
+                        newExpressions.Add(new BinaryExpression(low.BinaryOperator, high.FieldName, high.ComponentIndex, low.Value));
                         i++;
                         break;
                     default:

test/Microsoft.Health.Fhir.Shared.Tests.E2E/Rest/Import/ImportDateSearchTestFixture.cs

@@ -33,14 +33,21 @@ protected override async Task OnInitializedAsync()
                 p => SetObservation(p, "1980-05-11"),                // 1980-05-11T00:00:00.0000000 <-> 1980-05-11T23:59:59.9999999
                 p => SetObservation(p, "1980-05-11T16:32:15"),       // 1980-05-11T16:32:15.0000000 <-> 1980-05-11T16:32:15.9999999
                 p => SetObservation(p, "1980-05-11T16:32:15.500"),   // 1980-05-11T16:32:15.5000000 <-> 1980-05-11T16:32:15.5000000
-                p => SetObservation(p, "1981-01-01"));        // 1981-01-01T00:00:00.0000000 <-> 1981-12-31T23:59:59.9999999
-
+                p => SetObservation(p, "1981-01-01"),        // 1981-01-01T00:00:00.0000000 <-> 1981-12-31T23:59:59.9999999
+                p => SetObservationWithPeriod(p, "1980-05-16", "1980-05-17")); // 1980-05-16T00:00:00.0000000 <-> 1980-05-17T23:59:59.9999999
             void SetObservation(Observation observation, string date)
             {
                 observation.Status = ObservationStatus.Final;
                 observation.AddTestTag(FixtureTag);
                 observation.Effective = new FhirDateTime(date);
             }
+
+            void SetObservationWithPeriod(Observation observation, string startDate, string endDate)
+            {
+                observation.Status = ObservationStatus.Final;
+                observation.AddTestTag(FixtureTag);
+                observation.Effective = new Period(new FhirDateTime(startDate), new FhirDateTime(endDate));
+            }
         }
     }
 }