feature/edit/subset (#283)

* Changing query/subset API to only use Result on success, Error on error

* Creating an interservice API for getting query result subsets

* Updates to subset API

* RowStartIndex is now long
* Output of query/subset is a 2D array of DbCellValue
* Adding LongSkip method to LongList to allow skipping ahead by longs
* Moving LongList back to ServiceLayer utilities. Move refactoring

* Stubbing out request for edit/subset

* Initial implementation of getting edit rows

* Unit tests for RowEdit and RowDelete .GetEditRow

* Fixing major bugs in LongList implementation, adding much more thorough tests

* Adding some more unit tests and fixes to make unit tests pass

* Fixing comment

src/Microsoft.SqlTools.ServiceLayer/EditData/UpdateManagement/CellUpdate.cs

@@ -85,6 +85,22 @@ namespace Microsoft.SqlTools.ServiceLayer.EditData.UpdateManagement
 
         #region Properties
 
+        /// <summary>
+        /// Converts the cell update to a DbCellValue
+        /// </summary>
+        public DbCellValue AsDbCellValue
+        {
+            get
+            {
+                return new DbCellValue
+                {
+                    DisplayValue = ValueAsString,
+                    IsNull = Value == DBNull.Value,
+                    RawObject = Value
+                };
+            }
+        }
+
         /// <summary>
         /// The column that the cell will be placed in
         /// </summary>

src/Microsoft.SqlTools.ServiceLayer/EditData/UpdateManagement/RowCreate.cs

@@ -122,6 +122,26 @@ namespace Microsoft.SqlTools.ServiceLayer.EditData.UpdateManagement
             return command;
         }
 
+        /// <summary>
+        /// Generates a edit row that represents a row pending insertion
+        /// </summary>
+        /// <param name="cachedRow">Original, cached cell contents. (Should be null in this case)</param>
+        /// <returns>EditRow of pending update</returns>
+        public override EditRow GetEditRow(DbCellValue[] cachedRow)
+        {
+            // Iterate over the new cells. If they are null, generate a blank value
+            DbCellValue[] editCells = newCells.Select(cell => cell == null
+                    ? new DbCellValue {DisplayValue = string.Empty, IsNull = false, RawObject = null}
+                    : cell.AsDbCellValue)
+                .ToArray();
+            return new EditRow
+            {
+                Id = RowId,
+                Cells = editCells,
+                State = EditRow.EditRowState.DirtyInsert
+            };
+        }
+
         /// <summary>
         /// Generates the INSERT INTO statement that will apply the row creation
         /// </summary>

src/Microsoft.SqlTools.ServiceLayer/EditData/UpdateManagement/RowDelete.cs

@@ -9,6 +9,7 @@ using System.Globalization;
 using System.Threading.Tasks;
 using Microsoft.SqlTools.ServiceLayer.EditData.Contracts;
 using Microsoft.SqlTools.ServiceLayer.QueryExecution;
+using Microsoft.SqlTools.ServiceLayer.QueryExecution.Contracts;
 using Microsoft.SqlTools.Utility;
 
 namespace Microsoft.SqlTools.ServiceLayer.EditData.UpdateManagement
@@ -72,6 +73,24 @@ namespace Microsoft.SqlTools.ServiceLayer.EditData.UpdateManagement
             return command;
         }
 
+        /// <summary>
+        /// Generates a edit row that represents a row pending deletion. All the original cells are
+        /// intact but the state is dirty.
+        /// </summary>
+        /// <param name="cachedRow">Original, cached cell contents</param>
+        /// <returns>EditRow that is pending deletion</returns>
+        public override EditRow GetEditRow(DbCellValue[] cachedRow)
+        {
+            Validate.IsNotNull(nameof(cachedRow), cachedRow);
+
+            return new EditRow
+            {
+                Id = RowId,
+                Cells = cachedRow,
+                State = EditRow.EditRowState.DirtyDelete
+            };
+        }
+
         /// <summary>
         /// Generates a DELETE statement to delete this row
         /// </summary>

src/Microsoft.SqlTools.ServiceLayer/EditData/UpdateManagement/RowEdit.cs

@@ -85,6 +85,14 @@ namespace Microsoft.SqlTools.ServiceLayer.EditData.UpdateManagement
         /// <returns>Command to commit the change to the db</returns>
         public abstract DbCommand GetCommand(DbConnection connection);
 
+        /// <summary>
+        /// Generates a row that has the pending update applied. The dirty status of the row is
+        /// reflected in the returned EditRow.
+        /// </summary>
+        /// <param name="cachedRow">The original, cached row values</param>
+        /// <returns>An EditRow with the pending changes applied</returns>
+        public abstract EditRow GetEditRow(DbCellValue[] cachedRow);
+
         /// <summary>
         /// Converts the row edit into a SQL statement
         /// </summary>

src/Microsoft.SqlTools.ServiceLayer/EditData/UpdateManagement/RowUpdate.cs

@@ -113,6 +113,30 @@ namespace Microsoft.SqlTools.ServiceLayer.EditData.UpdateManagement
             return command;
         }
 
+        /// <summary>
+        /// Generates a edit row that represents a row with pending update. The cells pending
+        /// updates are merged into the unchanged cells.
+        /// </summary>
+        /// <param name="cachedRow">Original, cached cell contents</param>
+        /// <returns>EditRow with pending updates</returns>
+        public override EditRow GetEditRow(DbCellValue[] cachedRow)
+        {
+            Validate.IsNotNull(nameof(cachedRow), cachedRow);
+
+            // For each cell that is pending update, replace the db cell value with a new one
+            foreach (var cellUpdate in cellUpdates)
+            {
+                cachedRow[cellUpdate.Key] = cellUpdate.Value.AsDbCellValue;
+            }
+
+            return new EditRow
+            {
+                Id = RowId,
+                Cells = cachedRow,
+                State = EditRow.EditRowState.DirtyUpdate
+            };
+        }
+
         /// <summary>
         /// Constructs an update statement to change the associated row.
         /// </summary>