add median feature and undo accidental change

Author: adelinowona

src/MongoDB.Driver/Core/Misc/Feature.cs

@@ -83,6 +83,7 @@ public class Feature
         private static readonly Feature __loookupConciseSyntax = new Feature("LoookupConciseSyntax", WireVersion.Server50);
         private static readonly Feature __loookupDocuments= new Feature("LoookupDocuments", WireVersion.Server60);
         private static readonly Feature __mmapV1StorageEngine = new Feature("MmapV1StorageEngine", WireVersion.Zero, WireVersion.Server42);
+        private static readonly Feature __medianOperator = new Feature("MedianOperator", WireVersion.Server70);
         private static readonly Feature __percentileOperator = new Feature("PercentileOperator", WireVersion.Server70);
         private static readonly Feature __pickAccumulatorsNewIn52 = new Feature("PickAccumulatorsNewIn52", WireVersion.Server52);
         private static readonly Feature __rankFusionStage = new Feature("RankFusionStage", WireVersion.Server81);
@@ -402,6 +403,11 @@ public class Feature
         [Obsolete("This feature was removed in server version 4.2. As such, this property will be removed in a later release.")]
         public static Feature MmapV1StorageEngine => __mmapV1StorageEngine;
 
+        /// <summary>
+        /// Gets the $median operator added in 7.0
+        /// </summary>
+        public static Feature MedianOperator => __medianOperator;
+
         /// <summary>
         /// Gets the $percentile operator added in 7.0
         /// </summary>

tests/MongoDB.Driver.Tests/Linq/Linq3Implementation/Translators/ExpressionToAggregationExpressionTranslators/MethodTranslators/MedianMethodToAggregationExpressionTranslatorTests.cs

@@ -29,7 +29,7 @@ namespace MongoDB.Driver.Tests.Linq.Linq3Implementation.Translators.ExpressionTo
     public class MedianMethodToAggregationExpressionTranslatorTests : LinqIntegrationTest<MedianMethodToAggregationExpressionTranslatorTests.ClassFixture>
     {
         public MedianMethodToAggregationExpressionTranslatorTests(ClassFixture fixture)
-            : base(fixture, server => server.Supports(Feature.PercentileOperator)) // median and percentile were added in the same server version
+            : base(fixture, server => server.Supports(Feature.MedianOperator))
         {
         }
 

tests/MongoDB.Driver.Tests/Linq/Linq3ImplementationWithLinq2Tests/Translators/AggregateGroupTranslatorTests.cs

@@ -168,7 +168,7 @@ public void Should_translate_count_with_a_predicate()
         [Fact]
         public void Should_translate_median_with_embedded_projector()
         {
-            RequireServer.Check().Supports(Feature.PercentileOperator);
+            RequireServer.Check().Supports(Feature.MedianOperator);
 
             var result = Group(x => x.A, g => new { Result = g.Median(x=> x.C.E.F) });
 
@@ -183,7 +183,7 @@ public void Should_translate_median_with_embedded_projector()
         [Fact]
         public void Should_translate_median_with_selected_projector()
         {
-            RequireServer.Check().Supports(Feature.PercentileOperator);
+            RequireServer.Check().Supports(Feature.MedianOperator);
 
             var result = Group(x => x.A, g => new { Result = g.Select(x => x.C.E.F).Median() });
 
@@ -567,7 +567,7 @@ public void Should_translate_complex_selector()
                         First : '$__agg2',
                         Last : '$__agg3',
                         Min : '$__agg4',
-                        Max : '$__agg5'
+                        Max : '$__agg5',
                         _id : 0
                     }
                 }");