Add an option for copying with trailing line break in STS (#2122)

src/Microsoft.SqlTools.ServiceLayer/QueryExecution/Contracts/CopyResultsRequest.cs

@@ -27,6 +27,11 @@ namespace Microsoft.SqlTools.ServiceLayer.QueryExecution.Contracts
         /// </summary>
         public bool RemoveNewLines { get; set; }
 
+        /// <summary>
+        /// Whether to avoid adding a line break between rows during row concatenation for copying result when the previous row already has a trailing line break.
+        /// </summary>
+        public bool AvoidNewLineAfterTailingLineBreak { get; set; }
+
         /// <summary>
         /// Whether to include the column headers.
         /// </summary>

src/Microsoft.SqlTools.ServiceLayer/QueryExecution/QueryExecutionService.cs

@@ -789,7 +789,7 @@ namespace Microsoft.SqlTools.ServiceLayer.QueryExecution
                             }
                         }
                         // Add line break if this is not the last row in all selections.
-                        if (rowIndex + pageStartRowIndex != lastRowIndex)
+                        if (rowIndex + pageStartRowIndex != lastRowIndex && (!builder.ToString().EndsWith(Environment.NewLine) || !requestParams.AvoidNewLineAfterTailingLineBreak))
                         {
                             builder.Append(Environment.NewLine);
                         }