CSHARP-3314: Add a Create factory method to TranslationContext.

Author: rstam

src/MongoDB.Driver/Linq/Linq3Implementation/LinqProviderV3.cs

@@ -46,7 +46,7 @@ internal override BsonValue TranslateExpressionToAggregateExpression<TSource, TR
             IBsonSerializerRegistry serializerRegistry,
             ExpressionTranslationOptions translationOptions)
         {
-            var context = new TranslationContext();
+            var context = TranslationContext.Create(expression, sourceSerializer);
             var translation = ExpressionToAggregationExpressionTranslator.TranslateLambdaBody(context, expression, sourceSerializer, asRoot: true);
             var simplifiedAst = AstSimplifier.Simplify(translation.Ast);
 
@@ -70,7 +70,7 @@ internal override RenderedFieldDefinition TranslateExpressionToField<TDocument>(
             IBsonSerializerRegistry serializerRegistry)
         {
             var parameter = expression.Parameters.Single();
-            var context = new TranslationContext();
+            var context = TranslationContext.Create(expression, documentSerializer);
             var symbol = context.CreateSymbol(parameter, documentSerializer, isCurrent: true);
             context = context.WithSymbol(symbol);
             var field = ExpressionToFilterFieldTranslator.Translate(context, expression.Body);
@@ -85,7 +85,7 @@ internal override RenderedFieldDefinition<TField> TranslateExpressionToField<TDo
             bool allowScalarValueForArrayField)
         {
             var parameter = expression.Parameters.Single();
-            var context = new TranslationContext();
+            var context = TranslationContext.Create(expression, documentSerializer);
             var symbol = context.CreateSymbol(parameter, documentSerializer, isCurrent: true);
             context = context.WithSymbol(symbol);
             var field = ExpressionToFilterFieldTranslator.Translate(context, expression.Body);
@@ -102,7 +102,7 @@ internal override BsonDocument TranslateExpressionToFilter<TDocument>(
             IBsonSerializer<TDocument> documentSerializer,
             IBsonSerializerRegistry serializerRegistry)
         {
-            var context = new TranslationContext();
+            var context = TranslationContext.Create(expression, documentSerializer);
             var filter = ExpressionToFilterTranslator.TranslateLambda(context, expression, documentSerializer);
 
             return filter.Render().AsBsonDocument;
@@ -134,7 +134,7 @@ internal override RenderedProjectionDefinition<TOutput> TranslateExpressionToPro
             IBsonSerializerRegistry serializerRegistry,
             ExpressionTranslationOptions translationOptions)
         {
-            var context = new TranslationContext();
+            var context = TranslationContext.Create(expression, inputSerializer);
             var translation = ExpressionToAggregationExpressionTranslator.TranslateLambdaBody(context, expression, inputSerializer, asRoot: true);
             var (projectStage, projectionSerializer) = ProjectionHelper.CreateProjectStage(translation);
             var simplifiedProjectStage = AstSimplifier.Simplify(projectStage);

src/MongoDB.Driver/Linq/Linq3Implementation/Translators/ExpressionToExecutableQueryTranslators/ExpressionToExecutableQueryTranslator.cs

@@ -30,8 +30,7 @@ public static ExecutableQuery<TDocument, IAsyncCursor<TOutput>> Translate<TDocum
         {
             expression = PartialEvaluator.EvaluatePartially(expression);
 
-            var knownSerializersRegistry = KnownSerializerFinder.FindKnownSerializers(expression, (IBsonDocumentSerializer)provider.CollectionDocumentSerializer);
-            var context = new TranslationContext(knownSerializersRegistry);
+            var context = TranslationContext.Create(expression, provider.CollectionDocumentSerializer);
             var pipeline = ExpressionToPipelineTranslator.Translate(context, expression);
 
             return ExecutableQuery.Create(
@@ -45,8 +44,7 @@ public static ExecutableQuery<TDocument, TResult> TranslateScalar<TDocument, TRe
         {
             expression = PartialEvaluator.EvaluatePartially(expression);
 
-            var knownSerializersRegistry = KnownSerializerFinder.FindKnownSerializers(expression, (IBsonDocumentSerializer)provider.CollectionDocumentSerializer);
-            var context = new TranslationContext(knownSerializersRegistry);
+            var context = TranslationContext.Create(expression, provider.CollectionDocumentSerializer);
             var methodCallExpression = (MethodCallExpression)expression;
             switch (methodCallExpression.Method.Name)
             {

src/MongoDB.Driver/Linq/Linq3Implementation/Translators/TranslationContext.cs

@@ -24,22 +24,21 @@ namespace MongoDB.Driver.Linq.Linq3Implementation.Translators
 {
     internal class TranslationContext
     {
+        #region static
+        public static TranslationContext Create(Expression expression, IBsonSerializer serializer)
+        {
+            var symbolTable = new SymbolTable();
+            var nameGenerator = new NameGenerator();
+            var knownSerializersRegistry = KnownSerializerFinder.FindKnownSerializers(expression, (IBsonDocumentSerializer)serializer);
+            return new TranslationContext(symbolTable, nameGenerator, knownSerializersRegistry);
+        }
+        #endregion
+
         // private fields
         private readonly KnownSerializersRegistry _knownKnownSerializersRegistry;
         private readonly NameGenerator _nameGenerator;
         private readonly SymbolTable _symbolTable;
 
-        // constructors
-        public TranslationContext()
-            : this(new SymbolTable(), new NameGenerator(), new KnownSerializersRegistry())
-        {
-        }
-
-        public TranslationContext(KnownSerializersRegistry knownSerializersRegistry)
-            : this(new SymbolTable(), new NameGenerator(), knownSerializersRegistry)
-        {
-        }
-
         private TranslationContext(SymbolTable symbolTable, NameGenerator nameGenerator, KnownSerializersRegistry knownSerializersRegistry)
         {
             _symbolTable = Ensure.IsNotNull(symbolTable, nameof(symbolTable));

tests/MongoDB.Driver.Tests/Linq/Linq2ImplementationTestsOnLinq3/Translators/AggregateGroupTranslatorTests.cs

@@ -554,8 +554,7 @@ private ProjectedResult<TResult> Group<TKey, TResult>(Expression<Func<Root, TKey
                 .Select(groupProjector);
 
             var collectionSerializer = (IBsonDocumentSerializer)BsonSerializer.LookupSerializer<Root>();
-            var knownSerializersRegistry = KnownSerializerFinder.FindKnownSerializers(queryable.Expression, collectionSerializer);
-            var context = new TranslationContext(knownSerializersRegistry);
+            var context = TranslationContext.Create(queryable.Expression, collectionSerializer);
             var pipeline = ExpressionToPipelineTranslator.Translate(context, queryable.Expression);
             pipeline = AstPipelineOptimizer.Optimize(pipeline);
 

tests/MongoDB.Driver.Tests/Linq/Linq2ImplementationTestsOnLinq3/Translators/LegacyPredicateTranslatorTests.cs

@@ -1183,7 +1183,7 @@ private void Assert<TDocument>(Expression<Func<TDocument, bool>> expression, int
 
             var parameter = expression.Parameters.Single();
             var serializer = BsonSerializer.LookupSerializer<TDocument>();
-            var context = new TranslationContext();
+            var context = TranslationContext.Create(expression, serializer);
             var symbol = context.CreateSymbol(parameter, serializer, isCurrent: true);
             context = context.WithSymbol(symbol);
             var filterAst = ExpressionToFilterTranslator.Translate(context, expression.Body);

tests/MongoDB.Driver.Tests/Linq/Linq2ImplementationTestsOnLinq3/Translators/PredicateTranslatorTests.cs

@@ -1159,8 +1159,7 @@ public List<TDocument> Assert<TDocument>(IMongoCollection<TDocument> collection,
 
             var serializer = BsonSerializer.SerializerRegistry.GetSerializer<TDocument>();
             var parameter = filter.Parameters.Single();
-            var knownSerializersRegistry = KnownSerializerFinder.FindKnownSerializers(filter, (IBsonDocumentSerializer)serializer);
-            var context = new TranslationContext(knownSerializersRegistry);
+            var context = TranslationContext.Create(filter, serializer);
             var symbol = context.CreateSymbol(parameter, serializer, isCurrent: true);
             context = context.WithSymbol(symbol);
             var filterAst = ExpressionToFilterTranslator.Translate(context, filter.Body);

tests/MongoDB.Driver.Tests/Linq/Linq3ImplementationTests/Jira/CSharp1585Tests.cs

@@ -38,7 +38,7 @@ public void Nested_Any_should_translate_correctly()
             var parameter = expression.Parameters[0];
             var serializerRegistry = BsonSerializer.SerializerRegistry;
             var documentSerializer = serializerRegistry.GetSerializer<Document>();
-            var context = new TranslationContext();
+            var context = TranslationContext.Create(expression, documentSerializer);
             var symbol = context.CreateSymbol(parameter, documentSerializer, isCurrent: true);
             context = context.WithSymbol(symbol);
             var filter = ExpressionToFilterTranslator.Translate(context, expression.Body, exprOk: false);

tests/MongoDB.Driver.Tests/Linq/Linq3ImplementationTests/Translators/ExpressionToFilterTranslators/ExpressionTranslators/ModuloComparisonExpressionToFilterTranslatorTests.cs

@@ -184,7 +184,7 @@ private void Assert(AstFilter result, string path, BsonValue divisor, BsonValue
         private TranslationContext CreateContext(ParameterExpression parameter)
         {
             var serializer = BsonSerializer.LookupSerializer(parameter.Type);
-            var context = new TranslationContext();
+            var context = TranslationContext.Create(parameter, serializer);
             var symbol = context.CreateSymbol(parameter, serializer, isCurrent: true);
             return context.WithSymbol(symbol);
         }