Fix up various nullability warnings

FAnsiSql/DatabaseOperationArgs.cs

@@ -58,7 +58,7 @@ public int ExecuteNonQuery(DbCommand cmd)
     /// </summary>
     /// <param name="cmd"></param>
     /// <exception cref="OperationCanceledException"></exception>
-    public object ExecuteScalar(DbCommand cmd)
+    public object? ExecuteScalar(DbCommand cmd)
     {
         return Execute(cmd, ()=>cmd.ExecuteScalarAsync(CancellationToken));
     }

FAnsiSql/Discovery/BulkCopy.cs

@@ -119,7 +119,7 @@ protected void ConvertStringTypesToHardTypes(DataTable dt)
         {
             //if the destination column is a problematic type
             var dataType = discoveredColumn.DataType?.GetCSharpDataType();
-            if (!deciders.TryGetValue(dataType, out var decider)) continue;
+            if (dataType == null || !deciders.TryGetValue(dataType, out var decider)) continue;
             //if it's already not a string then that's fine (hopefully it's a legit Type e.g. DateTime!)
             if (dataColumn.DataType != typeof(string))
                 continue;

FAnsiSql/Discovery/DatabaseColumnRequest.cs

@@ -57,7 +57,7 @@ public sealed class DatabaseColumnRequest(string columnName, DatabaseTypeRequest
     /// Applies only if the <see cref="TypeRequested"/> is string based.  Setting this will override the default collation and specify
     /// a specific collation.  The value specified must be an installed collation supported by the DBMS
     /// </summary>
-    public string Collation { get; set; }
+    public string? Collation { get; set; }
 
     public DatabaseColumnRequest(string columnName, string explicitDbType, bool allowNulls = true) : this(columnName, (DatabaseTypeRequest?)null, allowNulls)
     {

FAnsiSql/Discovery/DiscoveredParameter.cs

@@ -13,5 +13,5 @@ public sealed class DiscoveredParameter(string parameterName)
     /// <summary>
     /// The <see cref="DiscoveredDataType"/> the parameter is declared as e.g. varchar(10)
     /// </summary>
-    public DiscoveredDataType DataType { get; set; }
+    public DiscoveredDataType? DataType { get; set; }
 }

FAnsiSql/Discovery/DiscoveredServer.cs

@@ -90,7 +90,7 @@ public DiscoveredServer(string? connectionString, DatabaseType databaseType)
     /// <param name="usernameIfAny">Optional username to set in the connection string</param>
     /// <param name="passwordIfAny">Optional password to set in the connection string</param>
     /// <exception cref="ImplementationNotFoundException"></exception>
-    public DiscoveredServer(string server, string database, DatabaseType databaseType, string usernameIfAny, string passwordIfAny)
+    public DiscoveredServer(string server, string? database, DatabaseType databaseType, string usernameIfAny, string passwordIfAny)
     {
         Helper = ImplementationManager.GetImplementation(databaseType).GetServerHelper();
 

Tests/FAnsiTests/DatabaseTests.cs

@@ -68,7 +68,7 @@ public void CheckFiles()
 
                 var constr = element.Element("ConnectionString")?.Value;
 
-                TestConnectionStrings.Add(databaseType,constr);
+                TestConnectionStrings.Add(databaseType,constr ?? throw new InvalidOperationException());
             }
         }
         catch (Exception exception)

Tests/FAnsiTests/Examples.cs

@@ -35,8 +35,8 @@ public void Simple_Example()
         Assert.Multiple(() =>
         {
             //Database types are compatible with all the data
-            Assert.That(table.DiscoverColumn("Date of Birth").DataType.SQLType, Is.EqualTo("datetime2"));
-            Assert.That(table.DiscoverColumn("Name").DataType.SQLType, Is.EqualTo("varchar(25)"));
+            Assert.That(table.DiscoverColumn("Date of Birth").DataType?.SQLType, Is.EqualTo("datetime2"));
+            Assert.That(table.DiscoverColumn("Name").DataType?.SQLType, Is.EqualTo("varchar(25)"));
 
             //And the (string) data is now properly typed and sat in our DBMS
             Assert.That(table.GetRowCount(), Is.EqualTo(2));
@@ -73,8 +73,8 @@ public void Example_TableCreation()
 
         //Table has 2 rows in it
         TestContext.WriteLine("Table {0} has {1} rows" ,table.GetFullyQualifiedName(), table.GetRowCount());
-        TestContext.WriteLine("Column Name is of type {0}", table.DiscoverColumn("Name").DataType.SQLType);
-        TestContext.WriteLine("Column DateOfBirth is of type {0}", table.DiscoverColumn("DateOfBirth").DataType.SQLType);
+        TestContext.WriteLine("Column Name is of type {0}", table.DiscoverColumn("Name").DataType?.SQLType);
+        TestContext.WriteLine("Column DateOfBirth is of type {0}", table.DiscoverColumn("DateOfBirth").DataType?.SQLType);
 
         using var con = server.GetConnection();
         con.Open();

Tests/FAnsiTests/ExtensionsTests.cs

@@ -11,18 +11,18 @@ public void Test_SetDoNotReType_RepeatCalls()
     {
         using var dt = new DataTable();
 
-        Assert.DoesNotThrow(()=>dt.SetDoNotReType(true));
+        Assert.DoesNotThrow(() => dt.SetDoNotReType(true));
 
-        dt.Columns.Add("FFF");
+        var dc = dt.Columns.Add("FFF");
 
-        Assert.That(dt.Columns["FFF"].GetDoNotReType(), Is.False);
+        Assert.That(dc.GetDoNotReType(), Is.False);
 
-        Assert.DoesNotThrow(()=>dt.SetDoNotReType(true));
+        Assert.DoesNotThrow(() => dt.SetDoNotReType(true));
 
-        Assert.That(dt.Columns["FFF"].GetDoNotReType());
+        Assert.That(dc.GetDoNotReType(), Is.True);
 
-        Assert.DoesNotThrow(()=>dt.SetDoNotReType(false));
+        Assert.DoesNotThrow(() => dt.SetDoNotReType(false));
 
-        Assert.That(dt.Columns["FFF"].GetDoNotReType(), Is.False);
+        Assert.That(dc.GetDoNotReType(), Is.False);
     }
 }

Tests/FAnsiTests/ManagedConnectionTests.cs

@@ -149,9 +149,9 @@ public void Test_GetManagedConnection_OngoingTransaction_WithCommitRollback(Data
             Assert.That(con.Connection.State, Is.EqualTo(ConnectionState.Open));
 
             if(commit)
-                ongoingCon.ManagedTransaction.CommitAndCloseConnection();
+                ongoingCon.ManagedTransaction?.CommitAndCloseConnection();
             else
-                ongoingCon.ManagedTransaction.AbandonAndCloseConnection();
+                ongoingCon.ManagedTransaction?.AbandonAndCloseConnection();
 
             //that should really have closed it!
             Assert.That(ongoingCon.Connection.State, Is.EqualTo(ConnectionState.Closed));
@@ -171,10 +171,10 @@ public void Test_ManagedTransaction_MultipleCancel(DatabaseType dbType)
         //pretend that there is an ongoing transaction already
         using (ongoingCon = db.Server.BeginNewTransactedConnection())
         {
-            ongoingCon.ManagedTransaction.AbandonAndCloseConnection();
-            ongoingCon.ManagedTransaction.AbandonAndCloseConnection();
-            ongoingCon.ManagedTransaction.AbandonAndCloseConnection();
-            ongoingCon.ManagedTransaction.CommitAndCloseConnection();
+            ongoingCon.ManagedTransaction?.AbandonAndCloseConnection();
+            ongoingCon.ManagedTransaction?.AbandonAndCloseConnection();
+            ongoingCon.ManagedTransaction?.AbandonAndCloseConnection();
+            ongoingCon.ManagedTransaction?.CommitAndCloseConnection();
         }
     }
 

Tests/FAnsiTests/Server/ServerTests.cs

@@ -62,18 +62,14 @@ public void ServerHelper_GetConnectionStringBuilder(DatabaseType type)
 
         var server = new DiscoveredServer(builder);
 
-        Assert.That(server.Name, Is.EqualTo("loco"));
-
-        //Oracle does not persist database in connection string
-        if(type == DatabaseType.Oracle)
-            Assert.That(server.GetCurrentDatabase(), Is.Null);
-        else
-            Assert.That(server.GetCurrentDatabase().GetRuntimeName(), Is.EqualTo("bob"));
-
         Assert.Multiple(() =>
         {
-            Assert.That(server.ExplicitUsernameIfAny, Is.EqualTo("franko"));
-            Assert.That(server.ExplicitPasswordIfAny, Is.EqualTo("wacky"));
+            Assert.That(server.Name,Is.EqualTo("loco"));
+
+            //Oracle does not persist database in connection string
+            Assert.That(server.GetCurrentDatabase()?.GetRuntimeName(),type == DatabaseType.Oracle ? Is.Null : Is.EqualTo("bob"));
+            Assert.That(server.ExplicitUsernameIfAny,Is.EqualTo("franko"));
+            Assert.That(server.ExplicitPasswordIfAny,Is.EqualTo("wacky"));
         });
     }
 
@@ -123,7 +119,7 @@ public void ServerHelper_ChangeDatabase(DatabaseType type,bool expectCaps)
             Assert.That(server.Name, Is.EqualTo("loco"));
 
             //this failure is already exposed by Server_Helper_GetConnectionStringBuilder
-            Assert.That(server.GetCurrentDatabase().GetRuntimeName(), Is.EqualTo(expectCaps ? "BOB" : "bob"));
+            Assert.That(server.GetCurrentDatabase()?.GetRuntimeName(), Is.EqualTo(expectCaps ? "BOB" : "bob"));
 
             Assert.That(server.ExplicitUsernameIfAny, Is.EqualTo("franko"));
             Assert.That(server.ExplicitPasswordIfAny, Is.EqualTo("wacky"));
@@ -135,7 +131,7 @@ public void ServerHelper_ChangeDatabase(DatabaseType type,bool expectCaps)
         {
             Assert.That(server.Name, Is.EqualTo("loco"));
 
-            Assert.That(server.GetCurrentDatabase().GetRuntimeName(), Is.EqualTo(expectCaps ? "OMGGGG" : "omgggg"));
+            Assert.That(server.GetCurrentDatabase()?.GetRuntimeName(), Is.EqualTo(expectCaps ? "OMGGGG" : "omgggg"));
             Assert.That(server.ExplicitUsernameIfAny, Is.EqualTo("franko"));
             Assert.That(server.ExplicitPasswordIfAny, Is.EqualTo("wacky"));
         });
@@ -160,7 +156,7 @@ public void ServerHelper_ChangeDatabase_AdHoc(DatabaseType type, bool useApiFirs
         Assert.Multiple(() =>
         {
             Assert.That(server.Name, Is.EqualTo("loco"));
-            Assert.That(server.GetCurrentDatabase().GetRuntimeName(), Is.EqualTo("bob"));
+            Assert.That(server.GetCurrentDatabase()?.GetRuntimeName(), Is.EqualTo("bob"));
         });
 
         //Use API to change databases
@@ -170,7 +166,7 @@ public void ServerHelper_ChangeDatabase_AdHoc(DatabaseType type, bool useApiFirs
             Assert.Multiple(() =>
             {
                 Assert.That(server.Name, Is.EqualTo("loco"));
-                Assert.That(server.GetCurrentDatabase().GetRuntimeName(), Is.EqualTo("omgggg"));
+                Assert.That(server.GetCurrentDatabase()?.GetRuntimeName(), Is.EqualTo("omgggg"));
             });
         }
 
@@ -179,14 +175,14 @@ public void ServerHelper_ChangeDatabase_AdHoc(DatabaseType type, bool useApiFirs
         Assert.Multiple(() =>
         {
             Assert.That(server.Name, Is.EqualTo("loco"));
-            Assert.That(server.GetCurrentDatabase().GetRuntimeName(), Is.EqualTo("Fisss"));
+            Assert.That(server.GetCurrentDatabase()?.GetRuntimeName(), Is.EqualTo("Fisss"));
         });
 
         server.Builder["Server"] = "Amagad";
         Assert.Multiple(() =>
         {
             Assert.That(server.Name, Is.EqualTo("Amagad"));
-            Assert.That(server.GetCurrentDatabase().GetRuntimeName(), Is.EqualTo("Fisss"));
+            Assert.That(server.GetCurrentDatabase()?.GetRuntimeName(), Is.EqualTo("Fisss"));
         });
     }
 
@@ -198,7 +194,7 @@ public void ServerHelper_ChangeDatabase_AdHoc(DatabaseType type, bool useApiFirs
     public void MoveData_BetweenServerTypes(DatabaseType from, DatabaseType to)
     {
         //Create some test data
-        var dtToMove = new DataTable();
+        using var dtToMove = new DataTable();
         dtToMove.Columns.Add("MyCol");
         dtToMove.Columns.Add("DateOfBirth");
         dtToMove.Columns.Add("Sanity");
@@ -207,7 +203,7 @@ public void MoveData_BetweenServerTypes(DatabaseType from, DatabaseType to)
         dtToMove.Rows.Add("Tony", null,"9.99");
         dtToMove.Rows.Add("Jez", new DateTime(2001, 05, 01),"100.0");
 
-        dtToMove.PrimaryKey = [dtToMove.Columns["MyCol"]];
+        dtToMove.PrimaryKey = [dtToMove.Columns["MyCol"] ?? throw new InvalidOperationException()];
 
         //Upload it to the first database
         var fromDb = GetTestDatabase(from);

Tests/FAnsiTests/Table/BadNamesTests.cs

@@ -89,7 +89,7 @@ public void BadNames_AlterType(DatabaseType dbType)
 
         var (_, badColumnName, _) = GetBadNames(dbType);
         var col = tbl.DiscoverColumn(badColumnName);
-        Assert.That(col.DataType.GetLengthIfString(), Is.EqualTo(100));
+        Assert.That(col.DataType?.GetLengthIfString(), Is.EqualTo(100));
 
         var varcharType = tbl.Database.Server.GetQuerySyntaxHelper().TypeTranslater.GetSQLDBTypeForCSharpType(new DatabaseTypeRequest(typeof(string),10));
 

Tests/FAnsiTests/Table/BulkInsertTest.cs

@@ -174,7 +174,7 @@ public void TestBulkInsert_Transaction(DatabaseType type)
                 Assert.That(tbl.GetRowCount(transaction.ManagedTransaction), Is.EqualTo(3));
             }
 
-            transaction.ManagedTransaction.CommitAndCloseConnection();
+            transaction.ManagedTransaction?.CommitAndCloseConnection();
         }
 
         //Transaction was committed final row count should be 3
@@ -220,7 +220,7 @@ public void TestBulkInsert_AbandonTransaction(DatabaseType type)
                 Assert.That(tbl.GetRowCount(transaction.ManagedTransaction), Is.EqualTo(3));
             }
 
-            transaction.ManagedTransaction.AbandonAndCloseConnection();
+            transaction.ManagedTransaction?.AbandonAndCloseConnection();
         }
 
         //We abandoned transaction so final rowcount should be 0
@@ -266,15 +266,15 @@ public void TestBulkInsert_AlterColumn_MidTransaction(DatabaseType type)
                 var col = tbl.DiscoverColumn("Name", transaction.ManagedTransaction);
 
                 //Make it bigger
-                col.DataType.Resize(100, transaction.ManagedTransaction);
+                col.DataType?.Resize(100, transaction.ManagedTransaction);
 
                 bulk.Upload(dt);
 
                 //inside transaction the count is 3
                 Assert.That(tbl.GetRowCount(transaction.ManagedTransaction), Is.EqualTo(3));
             }
 
-            transaction.ManagedTransaction.CommitAndCloseConnection();
+            transaction.ManagedTransaction?.CommitAndCloseConnection();
         }
 
         //We abandoned transaction so final rowcount should be 0
@@ -501,9 +501,9 @@ public void UnmatchedColumnsBulkInsertTest_UsesDefaultValues_TwoLargeBatches_Pas
             //give it 300 ms delay (simulates user cancelling not DbCommand.Timeout expiring)
             using var cts = new CancellationTokenSource(300);
             //GetDataTable should have been cancelled at the database level
-            Assert.Throws<OperationCanceledException>(()=>tbl.GetDataTable(new DatabaseOperationArgs(con.ManagedTransaction,50000,
+            Assert.Throws<OperationCanceledException>(()=>tbl.GetDataTable(new DatabaseOperationArgs(con.ManagedTransaction ?? throw new InvalidOperationException(),50000,
                 cts.Token)));
-            tbl.GetDataTable(new DatabaseOperationArgs(con.ManagedTransaction,50000, default));
+            tbl.GetDataTable(new DatabaseOperationArgs(con.ManagedTransaction ?? throw new InvalidOperationException(),50000, default));
         }