CSHARP-5541: move rankFusion methods to IAggregateFluentExtensions

src/MongoDB.Driver/AggregateFluent.cs

@@ -257,28 +257,6 @@ public override IAggregateFluent<TNewResult> Project<TNewResult>(ProjectionDefin
             return WithPipeline(_pipeline.Project(projection));
         }
 
-        public override IAggregateFluent<TNewResult> RankFusion<TNewResult>(
-            Dictionary<string, PipelineDefinition<TResult, TNewResult>> pipelines,
-            Dictionary<string, double> weights = null,
-            RankFusionOptions<TNewResult> options = null)
-        {
-            return WithPipeline(_pipeline.RankFusion(pipelines, weights, options));
-        }
-
-        public override IAggregateFluent<TNewResult> RankFusion<TNewResult>(
-            PipelineDefinition<TResult, TNewResult>[] pipelines,
-            RankFusionOptions<TNewResult> options = null)
-        {
-            return WithPipeline(_pipeline.RankFusion(pipelines, options));
-        }
-
-        public override IAggregateFluent<TNewResult> RankFusion<TNewResult>(
-            (PipelineDefinition<TResult, TNewResult>, double?)[] pipelinesWithWeights,
-            RankFusionOptions<TNewResult> options = null)
-        {
-            return WithPipeline(_pipeline.RankFusion(pipelinesWithWeights, options));
-        }
-
         public override IAggregateFluent<TNewResult> ReplaceRoot<TNewResult>(AggregateExpressionDefinition<TResult, TNewResult> newRoot)
         {
             return WithPipeline(_pipeline.ReplaceRoot(newRoot));

src/MongoDB.Driver/AggregateFluentBase.cs

@@ -225,29 +225,6 @@ public virtual Task<IAsyncCursor<TResult>> OutAsync(IMongoCollection<TResult> ou
         /// <inheritdoc />
         public abstract IAggregateFluent<TNewResult> Project<TNewResult>(ProjectionDefinition<TResult, TNewResult> projection);
 
-        /// <inheritdoc />
-        public virtual IAggregateFluent<TNewResult> RankFusion<TNewResult>(
-            Dictionary<string, PipelineDefinition<TResult, TNewResult>> pipelines,
-            Dictionary<string, double> weights = null,
-            RankFusionOptions<TNewResult> options = null)
-        {
-            throw new NotImplementedException();
-        }
-
-        /// <inheritdoc />
-        public virtual IAggregateFluent<TNewResult> RankFusion<TNewResult>(PipelineDefinition<TResult, TNewResult>[] pipelines, RankFusionOptions<TNewResult> options = null)
-        {
-            throw new NotImplementedException();
-        }
-
-        /// <inheritdoc />
-        public virtual IAggregateFluent<TNewResult> RankFusion<TNewResult>(
-            (PipelineDefinition<TResult, TNewResult>, double?)[] pipelinesWithWeights,
-            RankFusionOptions<TNewResult> options = null)
-        {
-            throw new NotImplementedException();
-        }
-
         /// <inheritdoc />
         public virtual IAggregateFluent<TNewResult> ReplaceRoot<TNewResult>(AggregateExpressionDefinition<TResult, TNewResult> newRoot)
         {

src/MongoDB.Driver/IAggregateFluent.cs

@@ -365,41 +365,6 @@ IAggregateFluent<TNewResult> Lookup<TForeignDocument, TAsElement, TAs, TNewResul
         /// </returns>
         IAggregateFluent<TNewResult> Project<TNewResult>(ProjectionDefinition<TResult, TNewResult> projection);
 
-        /// <summary>
-        /// Appends a $rankFusion stage to the pipeline.
-        /// </summary>
-        /// <typeparam name="TNewResult">The type of the new result.</typeparam>
-        /// <param name="pipelines">The map of named pipelines whose results will be combined. The pipelines must operate on the same collection.</param>
-        /// <param name="weights">The map of pipeline names to non-negative numerical weights determining result importance during combination. Default weight is 1 when unspecified.</param>
-        /// <param name="options">The rankFusion options.</param>
-        /// <returns>The fluent aggregate interface.</returns>
-        IAggregateFluent<TNewResult> RankFusion<TNewResult>(
-            Dictionary<string, PipelineDefinition<TResult, TNewResult>> pipelines,
-            Dictionary<string, double> weights = null,
-            RankFusionOptions<TNewResult> options = null);
-
-        /// <summary>
-        /// Appends a $rankFusion stage to the pipeline. Pipelines will be automatically named as "pipeline1", "pipeline2", etc.
-        /// </summary>
-        /// <typeparam name="TNewResult">The type of the new result.</typeparam>
-        /// <param name="pipelines">The collection of pipelines whose results will be combined. The pipelines must operate on the same collection.</param>
-        /// <param name="options">The rankFusion options.</param>
-        /// <returns>The fluent aggregate interface.</returns>
-        IAggregateFluent<TNewResult> RankFusion<TNewResult>(
-            PipelineDefinition<TResult, TNewResult>[] pipelines,
-            RankFusionOptions<TNewResult> options = null);
-
-        /// <summary>
-        /// Appends a $rankFusion stage to the pipeline. Pipelines will be automatically named as "pipeline1", "pipeline2", etc.
-        /// </summary>
-        /// <typeparam name="TNewResult">The type of the new result.</typeparam>
-        /// <param name="pipelinesWithWeights">The collection of tuples containing (pipeline, weight) pairs. The pipelines must operate on the same collection.</param>
-        /// <param name="options">The rankFusion options.</param>
-        /// <returns>The fluent aggregate interface.</returns>
-        IAggregateFluent<TNewResult> RankFusion<TNewResult>(
-            (PipelineDefinition<TResult, TNewResult>, double?)[] pipelinesWithWeights,
-            RankFusionOptions<TNewResult> options = null);
-
         /// <summary>
         /// Appends a $replaceRoot stage to the pipeline.
         /// </summary>

src/MongoDB.Driver/IAggregateFluentExtensions.cs

@@ -563,6 +563,62 @@ public static IAggregateFluent<TNewResult> Project<TResult, TNewResult>(this IAg
             return aggregate.AppendStage(PipelineStageDefinitionBuilder.Project(projection));
         }
 
+        /// <summary>
+        /// Appends a $rankFusion stage to the pipeline.
+        /// </summary>
+        /// <typeparam name="TResult">The type of the result.</typeparam>
+        /// <typeparam name="TNewResult">The type of the new result.</typeparam>
+        /// <param name="aggregate">The aggregate.</param>
+        /// <param name="pipelines">The map of named pipelines whose results will be combined. The pipelines must operate on the same collection.</param>
+        /// <param name="weights">The map of pipeline names to non-negative numerical weights determining result importance during combination. Default weight is 1 when unspecified.</param>
+        /// <param name="options">The rankFusion options.</param>
+        /// <returns>The fluent aggregate interface.</returns>
+        public static IAggregateFluent<TNewResult> RankFusion<TResult, TNewResult>(
+            this IAggregateFluent<TResult> aggregate,
+            Dictionary<string, PipelineDefinition<TResult, TNewResult>> pipelines,
+            Dictionary<string, double> weights = null,
+            RankFusionOptions<TNewResult> options = null)
+        {
+            Ensure.IsNotNull(aggregate, nameof(aggregate));
+            return aggregate.AppendStage(PipelineStageDefinitionBuilder.RankFusion(pipelines, weights, options));
+        }
+
+        /// <summary>
+        /// Appends a $rankFusion stage to the pipeline. Pipelines will be automatically named as "pipeline1", "pipeline2", etc.
+        /// </summary>
+        /// <typeparam name="TResult">The type of the result.</typeparam>
+        /// <typeparam name="TNewResult">The type of the new result.</typeparam>
+        /// <param name="aggregate">The aggregate.</param>
+        /// <param name="pipelines">The collection of pipelines whose results will be combined. The pipelines must operate on the same collection.</param>
+        /// <param name="options">The rankFusion options.</param>
+        /// <returns>The fluent aggregate interface.</returns>
+        public static IAggregateFluent<TNewResult> RankFusion<TResult, TNewResult>(
+            this IAggregateFluent<TResult> aggregate,
+            PipelineDefinition<TResult, TNewResult>[] pipelines,
+            RankFusionOptions<TNewResult> options = null)
+        {
+            Ensure.IsNotNull(aggregate, nameof(aggregate));
+            return aggregate.AppendStage(PipelineStageDefinitionBuilder.RankFusion(pipelines, options));
+        }
+
+        /// <summary>
+        /// Appends a $rankFusion stage to the pipeline. Pipelines will be automatically named as "pipeline1", "pipeline2", etc.
+        /// </summary>
+        /// <typeparam name="TResult">The type of the result.</typeparam>
+        /// <typeparam name="TNewResult">The type of the new result.</typeparam>
+        /// <param name="aggregate">The aggregate.</param>
+        /// <param name="pipelinesWithWeights">The collection of tuples containing (pipeline, weight) pairs. The pipelines must operate on the same collection.</param>
+        /// <param name="options">The rankFusion options.</param>
+        /// <returns>The fluent aggregate interface.</returns>
+        public static IAggregateFluent<TNewResult> RankFusion<TResult, TNewResult>(
+            this IAggregateFluent<TResult> aggregate,
+            (PipelineDefinition<TResult, TNewResult>, double?)[] pipelinesWithWeights,
+            RankFusionOptions<TNewResult> options = null)
+        {
+            Ensure.IsNotNull(aggregate, nameof(aggregate));
+            return aggregate.AppendStage(PipelineStageDefinitionBuilder.RankFusion(pipelinesWithWeights, options));
+        }
+
         /// <summary>
         /// Appends a $replaceRoot stage to the pipeline.
         /// </summary>

src/MongoDB.Driver/Search/RankFusionScoreDetails.cs

@@ -30,7 +30,7 @@ public sealed class RankFusionScoreDetails
         /// <param name="value">The computed score which is the same as the score available via {$meta: "score"}.</param>
         /// <param name="description">Description of how the score was computed.</param>
         /// <param name="details">Info about how each input pipeline in the rankFusion stage contributed to the computed score.</param>
-        /// <seealso cref="IAggregateFluent{TResult}.RankFusion{TNewResult}(Dictionary{string,PipelineDefinition{TResult,TNewResult}}, Dictionary{string,double}, RankFusionOptions{TNewResult})"/>
+        /// <seealso cref="IAggregateFluentExtensions.RankFusion{TResult, TNewResult}(IAggregateFluent{TResult}, Dictionary{string,PipelineDefinition{TResult,TNewResult}}, Dictionary{string,double}, RankFusionOptions{TNewResult})"/>
         public RankFusionScoreDetails(double value, string description, BsonDocument[] details)
         {
             Value = value;