Trivial Sendable conformances

Either added, either made explicitly unavailable.

GRDB/Core/Configuration.swift

@@ -294,7 +294,7 @@ public struct Configuration {
     /// connection is opened.
     ///
     /// Related SQLite documentation: <https://www.sqlite.org/pragma.html#pragma_journal_mode>
-    public enum JournalModeConfiguration {
+    public enum JournalModeConfiguration: Sendable {
         /// The default setup has ``DatabaseQueue`` perform no specific
         /// configuration of the journal mode, and ``DatabasePool`` 
         /// configure the database for the WAL mode (just like the

GRDB/Core/Cursor.swift

@@ -733,6 +733,11 @@ public final class AnyCursor<Element>: Cursor {
     }
 }
 
+// Explicit non-conformance to Sendable: a type-erased cursor can't be more
+// sendable than non-sendable cursors (such as `DatabaseCursor`).
+@available(*, unavailable)
+extension AnyCursor: Sendable { }
+
 /// A `Cursor` that consumes and drops n elements from an underlying `Base`
 /// cursor before possibly returning the first available element.
 public final class DropFirstCursor<Base: Cursor> {
@@ -747,6 +752,11 @@ public final class DropFirstCursor<Base: Cursor> {
     }
 }
 
+// Explicit non-conformance to Sendable: `DropFirstCursor` is a mutable
+// class and there is no known reason for making it thread-safe.
+@available(*, unavailable)
+extension DropFirstCursor: Sendable { }
+
 extension DropFirstCursor: Cursor {
     public func next() throws -> Base.Element? {
         while dropped < limit {
@@ -773,6 +783,11 @@ public final class DropWhileCursor<Base: Cursor> {
     }
 }
 
+// Explicit non-conformance to Sendable: `DropWhileCursor` is a mutable
+// class and there is no known reason for making it thread-safe.
+@available(*, unavailable)
+extension DropWhileCursor: Sendable { }
+
 extension DropWhileCursor: Cursor {
     public func next() throws -> Base.Element? {
         if predicateHasFailed {
@@ -818,6 +833,11 @@ public final class EnumeratedCursor<Base: Cursor> {
     }
 }
 
+// Explicit non-conformance to Sendable: `EnumeratedCursor` is a mutable
+// class and there is no known reason for making it thread-safe.
+@available(*, unavailable)
+extension EnumeratedCursor: Sendable { }
+
 extension EnumeratedCursor: Cursor {
     public func next() throws -> (Int, Base.Element)? {
         guard let element = try base.next() else { return nil }
@@ -875,6 +895,11 @@ public final class FlattenCursor<Base: Cursor> where Base.Element: Cursor {
     }
 }
 
+// Explicit non-conformance to Sendable: `EnumeratedCursor` is a mutable
+// class and there is no known reason for making it thread-safe.
+@available(*, unavailable)
+extension FlattenCursor: Sendable { }
+
 extension FlattenCursor: Cursor {
     public func next() throws -> Base.Element.Element? {
         while true {
@@ -901,6 +926,11 @@ public final class MapCursor<Base: Cursor, Element> {
     }
 }
 
+// Explicit non-conformance to Sendable: There is no known reason for making
+// it thread-safe (`transform` a Sendable closure).
+@available(*, unavailable)
+extension MapCursor: Sendable { }
+
 extension MapCursor: Cursor {
     public func next() throws -> Element? {
         guard let element = try base.next() else { return nil }
@@ -927,6 +957,11 @@ public final class PrefixCursor<Base: Cursor> {
     }
 }
 
+// Explicit non-conformance to Sendable: `PrefixCursor` is a mutable
+// class and there is no known reason for making it thread-safe.
+@available(*, unavailable)
+extension PrefixCursor: Sendable { }
+
 extension PrefixCursor: Cursor {
     public func next() throws -> Base.Element? {
         if taken >= maxLength { return nil }
@@ -954,6 +989,11 @@ public final class PrefixWhileCursor<Base: Cursor> {
     }
 }
 
+// Explicit non-conformance to Sendable: `PrefixCursor` is a mutable
+// class and there is no known reason for making it thread-safe.
+@available(*, unavailable)
+extension PrefixWhileCursor: Sendable { }
+
 extension PrefixWhileCursor: Cursor {
     public func next() throws -> Base.Element? {
         if !predicateHasFailed, let nextElement = try base.next() {

GRDB/Core/Database+Schema.swift

@@ -997,7 +997,7 @@ extension Database {
 ///
 /// - [pragma `table_info`](https://www.sqlite.org/pragma.html#pragma_table_info)
 /// - [pragma `table_xinfo`](https://www.sqlite.org/pragma.html#pragma_table_xinfo)
-public struct ColumnInfo: FetchableRecord {
+public struct ColumnInfo: FetchableRecord, Sendable {
     let cid: Int
     let hidden: Int?
 
@@ -1083,9 +1083,9 @@ public struct ColumnInfo: FetchableRecord {
 ///
 /// - [pragma `index_list`](https://www.sqlite.org/pragma.html#pragma_index_list)
 /// - [pragma `index_info`](https://www.sqlite.org/pragma.html#pragma_index_info)
-public struct IndexInfo {
+public struct IndexInfo: Sendable{
     /// The origin of an index.
-    public struct Origin: RawRepresentable, Equatable, DatabaseValueConvertible {
+    public struct Origin: RawRepresentable, Equatable, DatabaseValueConvertible, Sendable {
         public var rawValue: String
 
         public init(rawValue: String) {
@@ -1158,7 +1158,7 @@ public struct IndexInfo {
 /// ```
 ///
 /// Related SQLite documentation: <https://www.sqlite.org/pragma.html#pragma_foreign_key_check>
-public struct ForeignKeyViolation {
+public struct ForeignKeyViolation: Sendable {
     /// The name of the table that contains the foreign key.
     public var originTable: String
 
@@ -1307,7 +1307,7 @@ extension ForeignKeyViolation: CustomStringConvertible {
 /// pk.rowIDColumn // nil
 /// pk.isRowID     // false
 /// ```
-public struct PrimaryKeyInfo {
+public struct PrimaryKeyInfo: Sendable {
     private enum Impl {
         /// The hidden rowID.
         case hiddenRowID
@@ -1433,7 +1433,7 @@ public struct PrimaryKeyInfo {
 /// `Database` method.
 ///
 /// Related SQLite documentation: [pragma `foreign_key_list`](https://www.sqlite.org/pragma.html#pragma_foreign_key_list).
-public struct ForeignKeyInfo {
+public struct ForeignKeyInfo: Sendable {
     /// The first column in the output of the `foreign_key_list` pragma.
     public var id: Int
 

GRDB/Core/Database+Statements.swift

@@ -361,6 +361,11 @@ public class SQLStatementCursor {
     }
 }
 
+// Explicit non-conformance to Sendable: database cursors must be used from
+// a serialized database access dispatch queue.
+@available(*, unavailable)
+extension SQLStatementCursor: Sendable { }
+
 extension SQLStatementCursor: Cursor {
     public func next() throws -> Statement? {
         guard offset < cString.count - 1 /* trailing \0 */ else {

GRDB/Core/Database.swift

@@ -1729,6 +1729,11 @@ public final class Database: CustomStringConvertible, CustomDebugStringConvertib
     }
 }
 
+// Explicit non-conformance to Sendable: `Database` must be used from a
+// serialized database access dispatch queue (see `SerializedDatabase`).
+@available(*, unavailable)
+extension Database: Sendable { }
+
 #if SQLITE_HAS_CODEC
 extension Database {
 
@@ -1854,7 +1859,7 @@ extension Database {
     /// The available checkpoint modes.
     ///
     /// Related SQLite documentation: <https://www.sqlite.org/c3ref/wal_checkpoint_v2.html>
-    public enum CheckpointMode: CInt {
+    public enum CheckpointMode: CInt, Sendable {
         /// The `SQLITE_CHECKPOINT_PASSIVE` mode.
         case passive = 0
 
@@ -1873,7 +1878,7 @@ extension Database {
     /// Related SQLite documentation:
     /// - <https://www.sqlite.org/datatype3.html#collating_sequences>
     /// - <https://www.sqlite.org/datatype3.html#collation>
-    public struct CollationName: RawRepresentable, Hashable {
+    public struct CollationName: RawRepresentable, Hashable, Sendable {
         public let rawValue: String
 
         /// Creates a collation name.
@@ -1962,7 +1967,7 @@ extension Database {
     /// An SQLite conflict resolution.
     ///
     /// Related SQLite documentation: <https://www.sqlite.org/lang_conflict.html>
-    public enum ConflictResolution: String {
+    public enum ConflictResolution: String, Sendable {
         /// The `ROLLBACK` conflict resolution.
         case rollback = "ROLLBACK"
 
@@ -1982,7 +1987,7 @@ extension Database {
     /// A foreign key action.
     ///
     /// Related SQLite documentation: <https://www.sqlite.org/foreignkeys.html>
-    public enum ForeignKeyAction: String {
+    public enum ForeignKeyAction: String, Sendable {
         /// The `CASCADE` foreign key action.
         case cascade = "CASCADE"
 
@@ -2005,7 +2010,7 @@ extension Database {
     /// ``Database/trace(options:_:)`` method.
     ///
     /// Related SQLite documentation: <https://www.sqlite.org/c3ref/c_trace.html>
-    public struct TracingOptions: OptionSet {
+    public struct TracingOptions: OptionSet, Sendable {
         /// The raw trace event code.
         public let rawValue: CInt
 
@@ -2138,15 +2143,15 @@ extension Database {
     ///
     /// Related SQLite documentation: <https://www.sqlite.org/lang_transaction.html>.
     @frozen
-    public enum TransactionCompletion {
+    public enum TransactionCompletion: Sendable {
         case commit
         case rollback
     }
 
     /// A transaction kind.
     ///
     /// Related SQLite documentation: <https://www.sqlite.org/lang_transaction.html>.
-    public enum TransactionKind: String {
+    public enum TransactionKind: String, Sendable {
         /// The `DEFERRED` transaction kind.
         case deferred = "DEFERRED"
 
@@ -2179,3 +2184,13 @@ extension Database {
         }
     }
 }
+
+// Explicit non-conformance to Sendable: a trace event contains transient
+// information.
+@available(*, unavailable)
+extension Database.TraceEvent: Sendable { }
+
+// Explicit non-conformance to Sendable: a trace event contains transient
+// information.
+@available(*, unavailable)
+extension Database.TraceEvent.Statement: Sendable { }

GRDB/Core/DatabaseBackupProgress.swift

@@ -1,7 +1,7 @@
 /// Describe the progress of a database backup.
 ///
 /// Related SQLite documentation: <https://www.sqlite.org/c3ref/backup_finish.html>
-public struct DatabaseBackupProgress {
+public struct DatabaseBackupProgress: Sendable {
     /// The number of pages still to be backed up.
     ///
     /// It is the result of the `sqlite3_backup_remaining` function.

GRDB/Core/DatabaseRegion.swift

@@ -40,7 +40,7 @@
 ///
 /// - ``isModified(byEventsOfKind:)``
 /// - ``isModified(by:)``
-public struct DatabaseRegion {
+public struct DatabaseRegion: Sendable {
     private let tableRegions: [CaseInsensitiveIdentifier: TableRegion]?
 
     private init(tableRegions: [CaseInsensitiveIdentifier: TableRegion]?) {

GRDB/Core/DatabaseValueConvertible.swift

@@ -222,6 +222,11 @@ public final class DatabaseValueCursor<Value: DatabaseValueConvertible>: Databas
     }
 }
 
+// Explicit non-conformance to Sendable: database cursors must be used from
+// a serialized database access dispatch queue.
+@available(*, unavailable)
+extension DatabaseValueCursor: Sendable { }
+
 /// DatabaseValueConvertible comes with built-in methods that allow to fetch
 /// cursors, arrays, or single values:
 ///

GRDB/Core/FetchRequest.swift

@@ -152,6 +152,11 @@ public struct PreparedRequest {
     }
 }
 
+// Explicit non-conformance to Sendable: `PreparedRequest` contains
+// a statement.
+@available(*, unavailable)
+extension PreparedRequest: Sendable { }
+
 extension PreparedRequest: Refinable { }
 
 // MARK: - AdaptedFetchRequest

GRDB/Core/Row.swift

@@ -245,6 +245,12 @@ public final class Row {
     }
 }
 
+// Explicit non-conformance to Sendable: a row contains transient
+// information. TODO GRDB7: split non sendable statement rows from sendable
+// copied rows.
+@available(*, unavailable)
+extension Row: Sendable { }
+
 extension Row {
 
     // MARK: - Columns
@@ -1377,6 +1383,11 @@ public final class RowCursor: DatabaseCursor {
     public func _element(sqliteStatement: SQLiteStatement) -> Row { _row }
 }
 
+// Explicit non-conformance to Sendable: database cursors must be used from
+// a serialized database access dispatch queue.
+@available(*, unavailable)
+extension RowCursor: Sendable { }
+
 extension Row {
 
     // MARK: - Fetching From Prepared Statement
@@ -2059,7 +2070,7 @@ typealias RowIndex = Row.Index
 
 extension Row {
     /// An index to a (column, value) pair in a ``Row``.
-    public struct Index {
+    public struct Index: Sendable {
         let index: Int
         init(_ index: Int) { self.index = index }
     }

GRDB/Core/RowAdapter.swift

@@ -378,7 +378,7 @@ extension RowAdapter {
 ///
 /// This limit adapter may turn out useful in some narrow use cases. You'll
 /// be happy to find it when you need it.
-public struct EmptyRowAdapter: RowAdapter {
+public struct EmptyRowAdapter: RowAdapter, Sendable {
     /// Creates an `EmptyRowAdapter`.
     public init() { }
 
@@ -403,7 +403,7 @@ public struct EmptyRowAdapter: RowAdapter {
 ///
 /// Note that columns that are not present in the dictionary are not present
 /// in the resulting adapted row.
-public struct ColumnMapping: RowAdapter {
+public struct ColumnMapping: RowAdapter, Sendable {
     /// A dictionary from mapped column names to column names in a base row.
     let mapping: [String: String]
 
@@ -444,7 +444,7 @@ public struct ColumnMapping: RowAdapter {
 /// // [c:2, d: 3]
 /// try Row.fetchOne(db, sql: sql, adapter: adapter)!
 /// ```
-public struct SuffixRowAdapter: RowAdapter {
+public struct SuffixRowAdapter: RowAdapter, Sendable {
     /// The suffix index
     let index: Int
 
@@ -473,7 +473,7 @@ public struct SuffixRowAdapter: RowAdapter {
 /// // [b:1 c:2]
 /// try Row.fetchOne(db, sql: sql, adapter: adapter)
 /// ```
-public struct RangeRowAdapter: RowAdapter {
+public struct RangeRowAdapter: RowAdapter, Sendable {
     /// The range
     let range: CountableRange<Int>
 

GRDB/Core/Statement.swift

@@ -623,6 +623,11 @@ public final class Statement {
     }
 }
 
+// Explicit non-conformance to Sendable: statements must be used from
+// a serialized database access dispatch queue.
+@available(*, unavailable)
+extension Statement: Sendable { }
+
 extension Statement: CustomStringConvertible {
     public var description: String {
         SchedulingWatchdog.allows(database) ? sql : "Statement"

GRDB/Core/StatementColumnConvertible.swift

@@ -241,6 +241,11 @@ where Value: DatabaseValueConvertible & StatementColumnConvertible
     }
 }
 
+// Explicit non-conformance to Sendable: database cursors must be used from
+// a serialized database access dispatch queue.
+@available(*, unavailable)
+extension FastDatabaseValueCursor: Sendable { }
+
 /// Types that adopt both DatabaseValueConvertible and
 /// StatementColumnConvertible can be efficiently initialized from
 /// database values.