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adelinowonaadelinowona
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add a new translator for dictionary indexer comparison cases
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‎src/MongoDB.Driver/Linq/Linq3Implementation/Translators/ExpressionToFilterTranslators/ExpressionTranslators/ComparisonExpressionToFilterTranslator.cs‎

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@@ -56,6 +56,11 @@ public static AstFilter Translate(TranslationContext context, BinaryExpression e
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return CountComparisonExpressionToFilterTranslator.Translate(context, expression, comparisonOperator, countExpression, sizeExpression);
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}
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if (DictionaryIndexerComparisonExpressionToFilterTranslator.CanTranslate(leftExpression, rightExpression))
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{
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return DictionaryIndexerComparisonExpressionToFilterTranslator.Translate(context, expression, comparisonOperator, (MethodCallExpression)leftExpression, (ConstantExpression)rightExpression);
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}
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if (GetTypeComparisonExpressionToFilterTranslator.CanTranslate(leftExpression, comparisonOperator, rightExpression))
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{
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return GetTypeComparisonExpressionToFilterTranslator.Translate(context, expression, (MethodCallExpression)leftExpression, comparisonOperator, (ConstantExpression)rightExpression);

‎src/MongoDB.Driver/Linq/Linq3Implementation/Translators/ExpressionToFilterTranslators/ExpressionTranslators/DictionaryIndexerComparisonExpressionToFilterTranslator.cs‎

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@@ -0,0 +1,93 @@
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/* Copyright 2010-present MongoDB Inc.
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*
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* Licensed under the Apache License, Version 2.0 (the "License");
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* you may not use this file except in compliance with the License.
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* You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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*/
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using System.Linq.Expressions;
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using MongoDB.Bson;
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using MongoDB.Bson.Serialization;
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using MongoDB.Bson.Serialization.Options;
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using MongoDB.Driver.Linq.Linq3Implementation.Ast.Filters;
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using MongoDB.Driver.Linq.Linq3Implementation.ExtensionMethods;
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using MongoDB.Driver.Linq.Linq3Implementation.Misc;
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using MongoDB.Driver.Linq.Linq3Implementation.Reflection;
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using MongoDB.Driver.Linq.Linq3Implementation.Translators.ExpressionToFilterTranslators.ToFilterFieldTranslators;
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namespace MongoDB.Driver.Linq.Linq3Implementation.Translators.ExpressionToFilterTranslators.ExpressionTranslators
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{
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internal static class DictionaryIndexerComparisonExpressionToFilterTranslator
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{
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public static bool CanTranslate(Expression leftExpression, Expression rightExpression)
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{
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return leftExpression is MethodCallExpression methodCallExpression &&
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rightExpression is ConstantExpression &&
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DictionaryMethod.IsGetItemWithKeyMethod(methodCallExpression.Method);
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}
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public static AstFilter Translate(TranslationContext context, Expression containingExpression, AstComparisonFilterOperator comparisonOperator, MethodCallExpression indexerExpression, ConstantExpression valueExpression)
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{
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var dictionaryExpression = indexerExpression.Object;
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var keyExpression = indexerExpression.Arguments[0];
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var fieldTranslation = ExpressionToFilterFieldTranslator.Translate(context, dictionaryExpression);
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if (fieldTranslation.Serializer is not IBsonDictionarySerializer dictionarySerializer)
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{
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throw new ExpressionNotSupportedException(containingExpression, because: $"class {fieldTranslation.Serializer.GetType().FullName} does not implement the IBsonDictionarySerializer interface");
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}
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var dictionaryRepresentation = dictionarySerializer.DictionaryRepresentation;
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var key = GetKeyStringConstant(containingExpression, keyExpression, dictionarySerializer.KeySerializer);
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var serializedValue = SerializationHelper.SerializeValue(dictionarySerializer.ValueSerializer, valueExpression, containingExpression);
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switch (dictionaryRepresentation)
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{
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case DictionaryRepresentation.Document:
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{
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var subField = fieldTranslation.SubField(key, dictionarySerializer.ValueSerializer);
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return AstFilter.Compare(subField.Ast, comparisonOperator, serializedValue);
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}
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case DictionaryRepresentation.ArrayOfArrays:
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case DictionaryRepresentation.ArrayOfDocuments:
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{
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var keyFieldName = dictionaryRepresentation == DictionaryRepresentation.ArrayOfArrays ? "0" : "k";
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var valueFieldName = dictionaryRepresentation == DictionaryRepresentation.ArrayOfArrays ? "1" : "v";
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var keyField = AstFilter.Field(keyFieldName);
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var valueField = AstFilter.Field(valueFieldName);
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var keyMatchFilter = AstFilter.Eq(keyField, key);
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var valueMatchFilter = AstFilter.Compare(valueField, comparisonOperator, serializedValue);
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var combinedFilter = AstFilter.And(keyMatchFilter, valueMatchFilter);
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return AstFilter.ElemMatch(fieldTranslation.Ast, combinedFilter);
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}
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default:
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throw new ExpressionNotSupportedException(containingExpression, because: $"Unexpected dictionary representation: {dictionaryRepresentation}");
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}
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}
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private static string GetKeyStringConstant(Expression expression, Expression keyExpression, IBsonSerializer keySerializer)
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{
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var key = keyExpression.GetConstantValue<object>(containingExpression: expression);
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var serializedKey = SerializationHelper.SerializeValue(keySerializer, key);
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if (serializedKey is not BsonString)
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{
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throw new ExpressionNotSupportedException(expression, because: "key did not serialize as a string");
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}
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return serializedKey.AsString;
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}
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}
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}

‎tests/MongoDB.Driver.Tests/Linq/Linq3Implementation/Jira/CSharp4443Tests.cs‎

Lines changed: 4 additions & 4 deletions
Original file line numberDiff line numberDiff line change
@@ -1556,7 +1556,7 @@ public void Where_DictionaryAsArrayOfArrays_IndexerAccess_should_work()
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.Where(x => x.Dictionary["life"] == 42);
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var stages = Translate(collection, queryable);
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AssertStages(stages, "{ $match : { $expr : { $eq : [{ $arrayElemAt : [{ $arrayElemAt : [{ $filter : { input : '$Dictionary', as : 'kvp', cond : { $eq : [{ $arrayElemAt : ['$$kvp', 0] }, 'life'] }, limit : 1 } }, 0] }, 1] }, 42] } } }");
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AssertStages(stages, "{ $match : { Dictionary : { $elemMatch : { '0' : 'life', '1' : 42 } } } }");
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var result = queryable.ToList();
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result.Should().ContainSingle();
@@ -1755,7 +1755,7 @@ public void Where_DictionaryAsArrayOfDocuments_IndexerAccess_should_work()
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.Where(x => x.Dictionary["life"] == 42);
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var stages = Translate(collection, queryable);
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AssertStages(stages, "{ $match : { $expr : { $eq : [{ $let : { vars : { this : { $arrayElemAt : [{ $filter : { input : '$Dictionary', as : 'kvp', cond : { $eq : ['$$kvp.k', 'life'] }, limit : 1 } }, 0] } }, in : '$$this.v' } }, 42] } } }");
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AssertStages(stages, "{ $match : { Dictionary : { $elemMatch : { k : 'life', v : 42 } } } }");
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var result = queryable.ToList();
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result.Should().ContainSingle();
@@ -2131,7 +2131,7 @@ public void Where_IDictionaryAsArrayOfArrays_IndexerAccess_should_work()
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.Where(x => x.DictionaryInterface["life"] == 42);
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var stages = Translate(collection, queryable);
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AssertStages(stages, "{ $match : { $expr : { $eq : [{ $arrayElemAt : [{ $arrayElemAt : [{ $filter : { input : '$DictionaryInterface', as : 'kvp', cond : { $eq : [{ $arrayElemAt : ['$$kvp', 0] }, 'life'] }, limit : 1 } }, 0] }, 1] }, 42] } } }");
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AssertStages(stages, "{ $match : { DictionaryInterface : { $elemMatch : { '0' : 'life', '1' : 42 } } } }");
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var result = queryable.ToList();
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result.Should().ContainSingle();
@@ -2312,7 +2312,7 @@ public void Where_IDictionaryAsArrayOfDocuments_IndexerAccess_should_work()
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.Where(x => x.DictionaryInterface["life"] == 42);
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var stages = Translate(collection, queryable);
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AssertStages(stages, "{ $match : { $expr : { $eq : [{ $let : { vars : { this : { $arrayElemAt : [{ $filter : { input : '$DictionaryInterface', as : 'kvp', cond : { $eq : ['$$kvp.k', 'life'] }, limit : 1 } }, 0] } }, in : '$$this.v' } }, 42] } } }");
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AssertStages(stages, "{ $match : { DictionaryInterface : { $elemMatch : { k : 'life', v : 42 } } } }");
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var result = queryable.ToList();
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result.Should().ContainSingle();

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