Merge pull request #16267 from rchande/fix15804

Show object creation intellisense when new is typed on the line befor…

src/EditorFeatures/CSharpTest/Completion/CompletionProviders/ObjectCreationCompletionProviderTests.cs

@@ -437,5 +437,21 @@ public async Task InExpressionBodiedMethod()
 ";
             await VerifyItemExistsAsync(markup, "object");
         }
+
+        [WorkItem(15804, "https://github.com/dotnet/roslyn/issues/15804")]
+        [Fact, Trait(Traits.Feature, Traits.Features.Completion)]
+        public async Task BeforeAttributeParsedAsImplicitArray()
+        {
+            var markup =
+@"class Program
+{
+    Program p = new $$ 
+
+    [STAThread]
+    static void Main() { }
+}
+";
+            await VerifyItemExistsAsync(markup, "Program");
+        }
     }
 }

src/Workspaces/CSharp/Portable/LanguageServices/CSharpTypeInferenceService.TypeInferrer.cs

@@ -218,6 +218,7 @@ protected override IEnumerable<TypeInferenceInfo> InferTypesWorker_DoNotCallDire
                     case ForEachStatementSyntax forEachStatement: return InferTypeInForEachStatement(forEachStatement, previousToken: token);
                     case ForStatementSyntax forStatement: return InferTypeInForStatement(forStatement, previousToken: token);
                     case IfStatementSyntax ifStatement: return InferTypeInIfStatement(ifStatement, token);
+                    case ImplicitArrayCreationExpressionSyntax implicitArray: return InferTypeInImplicitArrayCreation(implicitArray, token);
                     case InitializerExpressionSyntax initializerExpression: return InferTypeInInitializerExpression(initializerExpression, previousToken: token);
                     case LockStatementSyntax lockStatement: return InferTypeInLockStatement(lockStatement, token);
                     case MemberAccessExpressionSyntax memberAccessExpression: return InferTypeInMemberAccessExpression(memberAccessExpression, previousToken: token);
@@ -1207,6 +1208,11 @@ private IEnumerable<TypeInferenceInfo> InferTypeInIfStatement(IfStatementSyntax
                 return SpecializedCollections.SingletonEnumerable(new TypeInferenceInfo(this.Compilation.GetSpecialType(SpecialType.System_Boolean)));
             }
 
+            private IEnumerable<TypeInferenceInfo> InferTypeInImplicitArrayCreation(ImplicitArrayCreationExpressionSyntax implicitArray, SyntaxToken previousToken)
+            {
+                return InferTypes(implicitArray.SpanStart);
+            }
+
             private IEnumerable<TypeInferenceInfo> InferTypeInInitializerExpression(
                 InitializerExpressionSyntax initializerExpression,
                 ExpressionSyntax expressionOpt = null,