Drop support for Swift 5.5 (#336)

Author: fabianfett

Package.swift

@@ -1,4 +1,4 @@
-// swift-tools-version:5.5
+// swift-tools-version:5.6
 import PackageDescription
 
 let package = Package(

Sources/PostgresNIO/Connection/PostgresConnection.swift

@@ -8,7 +8,9 @@ import Logging
 import NIOPosix
 
 /// A Postgres connection. Use it to run queries against a Postgres server.
-public final class PostgresConnection {
+///
+/// Thread safety is achieved by dispatching all access to shared state onto the underlying EventLoop.
+public final class PostgresConnection: @unchecked Sendable {
     /// A Postgres connection ID
     public typealias ID = Int
 
@@ -449,7 +451,6 @@ extension PostgresConnection {
 
 // MARK: Async/Await Interface
 
-#if canImport(_Concurrency)
 extension PostgresConnection {
 
     /// Creates a new connection to a Postgres server.
@@ -513,7 +514,6 @@ extension PostgresConnection {
         return try await promise.futureResult.map({ $0.asyncSequence() }).get()
     }
 }
-#endif
 
 // MARK: EventLoopFuture interface
 
@@ -785,7 +785,3 @@ extension PostgresConnection.InternalConfiguration {
         self.requireBackendKeyData = config.connection.requireBackendKeyData
     }
 }
-
-#if swift(>=5.6)
-extension PostgresConnection: @unchecked Sendable {}
-#endif

Sources/PostgresNIO/Data/PostgresData.swift

@@ -1,7 +1,7 @@
 import NIOCore
 import struct Foundation.UUID
 
-public struct PostgresData: CustomStringConvertible, CustomDebugStringConvertible {
+public struct PostgresData: Sendable, CustomStringConvertible, CustomDebugStringConvertible {
     public static var null: PostgresData {
         return .init(type: .null)
     }
@@ -112,7 +112,3 @@ extension PostgresData: PostgresDataConvertible {
         return self
     }
 }
-
-#if swift(>=5.6)
-extension PostgresData: Sendable {}
-#endif

Sources/PostgresNIO/Data/PostgresDataType.swift

@@ -3,7 +3,7 @@
 /// Currently there a two wire formats supported:
 ///  - text
 ///  - binary
-public enum PostgresFormat: Int16 {
+public enum PostgresFormat: Int16, Sendable {
     case text = 0
     case binary = 1
 }
@@ -17,11 +17,6 @@ extension PostgresFormat: CustomStringConvertible {
     }
 }
 
-#if swift(>=5.6)
-extension PostgresFormat: Sendable {}
-#endif
-
-
 // TODO: The Codable conformance does not make any sense. Let's remove this with next major break.
 extension PostgresFormat: Codable {}
 
@@ -31,7 +26,7 @@ public typealias PostgresFormatCode = PostgresFormat
 
 /// The data type's raw object ID.
 /// Use `select * from pg_type where oid = <idhere>;` to lookup more information.
-public struct PostgresDataType: RawRepresentable, Hashable, CustomStringConvertible {
+public struct PostgresDataType: RawRepresentable, Sendable, Hashable, CustomStringConvertible {
     /// `0`
     public static let null = PostgresDataType(0)
     /// `16`
@@ -238,10 +233,6 @@ public struct PostgresDataType: RawRepresentable, Hashable, CustomStringConverti
     }
 }
 
-#if swift(>=5.6)
-extension PostgresDataType: Sendable {}
-#endif
-
 // TODO: The Codable conformance does not make any sense. Let's remove this with next major break.
 extension PostgresDataType: Codable {}
 

Sources/PostgresNIO/Data/PostgresRow.swift

@@ -7,7 +7,7 @@ import class Foundation.JSONDecoder
 /// - Warning: Please note that random access to cells in a ``PostgresRow`` have O(n) time complexity. If you require
 ///            random access to cells in O(1) create a new ``PostgresRandomAccessRow`` with the given row and
 ///            access it instead.
-public struct PostgresRow {
+public struct PostgresRow: Sendable {
     @usableFromInline
     let lookupTable: [String: Int]
     @usableFromInline
@@ -138,7 +138,7 @@ public struct PostgresRandomAccessRow {
     }
 }
 
-extension PostgresRandomAccessRow: RandomAccessCollection {
+extension PostgresRandomAccessRow: Sendable, RandomAccessCollection {
     public typealias Element = PostgresCell
     public typealias Index = Int
 
@@ -320,9 +320,3 @@ extension PostgresRow: CustomStringConvertible {
         return row.description
     }
 }
-
-#if swift(>=5.6)
-extension PostgresRow: Sendable {}
-
-extension PostgresRandomAccessRow: Sendable {}
-#endif

Sources/PostgresNIO/New/Messages/DataRow.swift

@@ -9,7 +9,7 @@ import NIOCore
 ///         Not putting `DataRow` in ``PSQLBackendMessage`` is our way to trick
 ///         the Swift compiler
 @usableFromInline
-struct DataRow: PostgresBackendMessage.PayloadDecodable, Equatable {
+struct DataRow: Sendable, PostgresBackendMessage.PayloadDecodable, Equatable {
     @usableFromInline
     var columnCount: Int16
     @usableFromInline
@@ -116,7 +116,3 @@ extension DataRow {
         return self[byteIndex]
     }
 }
-
-#if swift(>=5.5)
-extension DataRow: Sendable {}
-#endif

Sources/PostgresNIO/New/Messages/RowDescription.swift

@@ -9,7 +9,7 @@ import NIOCore
 ///         Not putting `DataRow` in ``PSQLBackendMessage`` is our way to trick
 ///         the Swift compiler.
 @usableFromInline
-struct RowDescription: PostgresBackendMessage.PayloadDecodable, Equatable {
+struct RowDescription: PostgresBackendMessage.PayloadDecodable, Sendable, Equatable {
     /// Specifies the object ID of the parameter data type.
     @usableFromInline
     var columns: [Column]
@@ -86,7 +86,3 @@ struct RowDescription: PostgresBackendMessage.PayloadDecodable, Equatable {
         return RowDescription(columns: result)
     }
 }
-
-#if swift(>=5.6)
-extension RowDescription.Column: Sendable {}
-#endif

Sources/PostgresNIO/New/PSQLRowStream.swift

@@ -1,7 +1,8 @@
 import NIOCore
 import Logging
 
-final class PSQLRowStream {
+// Thread safety is guaranteed in the RowStream through dispatching onto the NIO EventLoop.
+final class PSQLRowStream: @unchecked Sendable {
     private typealias AsyncSequenceSource = NIOThrowingAsyncSequenceProducer<DataRow, Error, AdaptiveRowBuffer, PSQLRowStream>.Source
 
     enum RowSource {
@@ -23,10 +24,7 @@ final class PSQLRowStream {
         case iteratingRows(onRow: (PostgresRow) throws -> (), EventLoopPromise<Void>, PSQLRowsDataSource)
         case waitingForAll([PostgresRow], EventLoopPromise<[PostgresRow]>, PSQLRowsDataSource)
         case consumed(Result<String, Error>)
-        
-        #if canImport(_Concurrency)
         case asyncSequence(AsyncSequenceSource, PSQLRowsDataSource)
-        #endif
     }
 
     internal let rowDescription: [RowDescription.Column]
@@ -64,8 +62,7 @@ final class PSQLRowStream {
     }
 
     // MARK: Async Sequence
-    
-    #if canImport(_Concurrency)
+
     func asyncSequence() -> PostgresRowSequence {
         self.eventLoop.preconditionInEventLoop()
 
@@ -150,7 +147,6 @@ final class PSQLRowStream {
             preconditionFailure("Invalid state: \(self.downstreamState)")
         }
     }
-    #endif
 
     // MARK: Consume in array
 
@@ -312,12 +308,10 @@ final class PSQLRowStream {
             self.downstreamState = .waitingForAll(rows, promise, dataSource)
             // immediately request more
             dataSource.request(for: self)
-        
-        #if canImport(_Concurrency)
+
         case .asyncSequence(let consumer, let source):
             let yieldResult = consumer.yield(contentsOf: newRows)
             self.executeActionBasedOnYieldResult(yieldResult, source: source)
-        #endif
 
         case .consumed(.success):
             preconditionFailure("How can we receive further rows, if we are supposed to be done")
@@ -353,12 +347,10 @@ final class PSQLRowStream {
         case .waitingForAll(let rows, let promise, _):
             self.downstreamState = .consumed(.success(commandTag))
             promise.succeed(rows)
-            
-        #if canImport(_Concurrency)
+
         case .asyncSequence(let source, _):
             source.finish()
             self.downstreamState = .consumed(.success(commandTag))
-        #endif
 
         case .consumed:
             break
@@ -380,13 +372,11 @@ final class PSQLRowStream {
         case .waitingForAll(_, let promise, _):
             self.downstreamState = .consumed(.failure(error))
             promise.fail(error)
-            
-        #if canImport(_Concurrency)
+
         case .asyncSequence(let consumer, _):
             consumer.finish(error)
             self.downstreamState = .consumed(.failure(error))
-        #endif
-            
+
         case .consumed:
             break
         }
@@ -432,8 +422,3 @@ protocol PSQLRowsDataSource {
     func cancel(for stream: PSQLRowStream)
 
 }
-
-#if swift(>=5.5)
-// Thread safety is guaranteed in the RowStream through dispatching onto the NIO EventLoop.
-extension PSQLRowStream: @unchecked Sendable {}
-#endif

Sources/PostgresNIO/New/PostgresCell.swift

@@ -1,7 +1,7 @@
 import NIOCore
 
 /// A representation of a cell value within a ``PostgresRow`` and ``PostgresRandomAccessRow``.
-public struct PostgresCell: Equatable {
+public struct PostgresCell: Sendable, Equatable {
     /// The cell's value as raw bytes.
     public var bytes: ByteBuffer?
     /// The cell's data type. This is important metadata when decoding the cell.
@@ -86,7 +86,3 @@ extension PostgresCell {
         try self.decode(T.self, context: .default, file: file, line: line)
     }
 }
-
-#if swift(>=5.6)
-extension PostgresCell: Sendable {}
-#endif

Sources/PostgresNIO/New/PostgresQuery.swift

@@ -1,7 +1,7 @@
 import NIOCore
 
 /// A Postgres SQL query, that can be executed on a Postgres server. Contains the raw sql string and bindings.
-public struct PostgresQuery: Hashable {
+public struct PostgresQuery: Sendable, Hashable {
     /// The query string
     public var sql: String
     /// The query binds
@@ -104,9 +104,9 @@ struct PSQLExecuteStatement {
     var rowDescription: RowDescription?
 }
 
-public struct PostgresBindings: Hashable {
+public struct PostgresBindings: Sendable, Hashable {
     @usableFromInline
-    struct Metadata: Hashable {
+    struct Metadata: Sendable, Hashable {
         @usableFromInline
         var dataType: PostgresDataType
         @usableFromInline
@@ -179,9 +179,3 @@ public struct PostgresBindings: Hashable {
         self.metadata.append(.init(dataType: postgresData.type, format: .binary))
     }
 }
-
-#if swift(>=5.6)
-extension PostgresQuery: Sendable {}
-extension PostgresBindings: Sendable {}
-extension PostgresBindings.Metadata: Sendable {}
-#endif