Adopt package access level

Change a l public declarations to the `package` access level, accept for:
- The `LanguageServerProtocol` module
- The `BuildServerProtocol` module
- `InProcessClient.InProcessSourceKitLSPClient`
- `LanguageServerProtocolJSONRPC` (I would like to create a more ergonomic API for this like `InProcessSourceKitLSPClient` in the future, but for now, we’ll leave it public)

Unfortunately, our pattern of marking functions as `@_spi(Testing) public` no longer works with the `package` access level because declarations at the `package` access level cannot be marked as SPI. I have decided to just mark these functions as `package`. Alternatives would be:
- Add an underscore to these functions, like we did for functions exposed for testing before the introduction of `SPI`
- Use `@testable` import in the test targets and mark the methods as `internal`

Resolves #1315
rdar://128295618

Author: ahoppen

Package.swift

@@ -1,4 +1,4 @@
-// swift-tools-version: 5.8
+// swift-tools-version: 5.9
 
 import Foundation
 import PackageDescription

Sources/Diagnose/DebugCommand.swift

@@ -12,8 +12,8 @@
 
 import ArgumentParser
 
-public struct DebugCommand: ParsableCommand {
-  public static let configuration = CommandConfiguration(
+package struct DebugCommand: ParsableCommand {
+  package static let configuration = CommandConfiguration(
     commandName: "debug",
     abstract: "Commands to debug sourcekit-lsp. Intended for developers of sourcekit-lsp",
     subcommands: [
@@ -24,5 +24,5 @@ public struct DebugCommand: ParsableCommand {
     ]
   )
 
-  public init() {}
+  package init() {}
 }

Sources/Diagnose/DiagnoseCommand.swift

@@ -40,8 +40,8 @@ fileprivate enum BundleComponent: String, CaseIterable, ExpressibleByArgument {
   case swiftFrontendCrashes = "swift-frontend-crashes"
 }
 
-public struct DiagnoseCommand: AsyncParsableCommand {
-  public static let configuration: CommandConfiguration = CommandConfiguration(
+package struct DiagnoseCommand: AsyncParsableCommand {
+  package static let configuration: CommandConfiguration = CommandConfiguration(
     commandName: "diagnose",
     abstract: "Creates a bundle containing information that help diagnose issues with sourcekit-lsp"
   )
@@ -109,7 +109,7 @@ public struct DiagnoseCommand: AsyncParsableCommand {
     ["/Library/Logs/DiagnosticReports", "~/Library/Logs/DiagnosticReports"]
   }
 
-  public init() {}
+  package init() {}
 
   @MainActor
   private func addSourcekitdCrashReproducer(toBundle bundlePath: URL) async throws {
@@ -341,7 +341,7 @@ public struct DiagnoseCommand: AsyncParsableCommand {
   }
 
   @MainActor
-  public func run() async throws {
+  package func run() async throws {
     // IMPORTANT: When adding information to this message, also add it to the message displayed in VS Code
     // (captureDiagnostics.ts in the vscode-swift repository)
     print(

Sources/Diagnose/IndexCommand.swift

@@ -52,8 +52,8 @@ private actor IndexLogMessageHandler: MessageHandler {
 
 }
 
-public struct IndexCommand: AsyncParsableCommand {
-  public static let configuration: CommandConfiguration = CommandConfiguration(
+package struct IndexCommand: AsyncParsableCommand {
+  package static let configuration: CommandConfiguration = CommandConfiguration(
     commandName: "index",
     abstract: "Index a project and print all the processes executed for it as well as their outputs"
   )
@@ -79,9 +79,9 @@ public struct IndexCommand: AsyncParsableCommand {
   @Option(help: "The path to the project that should be indexed")
   var project: String
 
-  public init() {}
+  package init() {}
 
-  public func run() async throws {
+  package func run() async throws {
     let options = SourceKitLSPOptions(
       backgroundIndexing: true,
       experimentalFeatures: Set(experimentalFeatures)

Sources/Diagnose/ReduceCommand.swift

@@ -18,8 +18,8 @@ import struct TSCBasic.AbsolutePath
 import class TSCBasic.Process
 import class TSCUtility.PercentProgressAnimation
 
-public struct ReduceCommand: AsyncParsableCommand {
-  public static let configuration: CommandConfiguration = CommandConfiguration(
+package struct ReduceCommand: AsyncParsableCommand {
+  package static let configuration: CommandConfiguration = CommandConfiguration(
     commandName: "reduce",
     abstract: "Reduce a single sourcekitd crash"
   )
@@ -65,10 +65,10 @@ public struct ReduceCommand: AsyncParsableCommand {
     }
   }
 
-  public init() {}
+  package init() {}
 
   @MainActor
-  public func run() async throws {
+  package func run() async throws {
     guard let sourcekitd = try await toolchain?.sourcekitd else {
       throw ReductionError("Unable to find sourcekitd.framework")
     }

Sources/Diagnose/ReduceFrontendCommand.swift

@@ -18,8 +18,8 @@ import struct TSCBasic.AbsolutePath
 import class TSCBasic.Process
 import class TSCUtility.PercentProgressAnimation
 
-public struct ReduceFrontendCommand: AsyncParsableCommand {
-  public static let configuration: CommandConfiguration = CommandConfiguration(
+package struct ReduceFrontendCommand: AsyncParsableCommand {
+  package static let configuration: CommandConfiguration = CommandConfiguration(
     commandName: "reduce-frontend",
     abstract: "Reduce a single swift-frontend crash"
   )
@@ -73,10 +73,10 @@ public struct ReduceFrontendCommand: AsyncParsableCommand {
     }
   }
 
-  public init() {}
+  package init() {}
 
   @MainActor
-  public func run() async throws {
+  package func run() async throws {
     guard let sourcekitd = try await toolchain?.sourcekitd else {
       throw ReductionError("Unable to find sourcekitd.framework")
     }

Sources/Diagnose/ReduceSwiftFrontend.swift

@@ -11,8 +11,7 @@
 //===----------------------------------------------------------------------===//
 
 @MainActor
-@_spi(Testing)
-public func reduceFrontendIssue(
+package func reduceFrontendIssue(
   frontendArgs: [String],
   using executor: SourceKitRequestExecutor,
   progressUpdate: (_ progress: Double, _ message: String) -> Void

Sources/Diagnose/RequestInfo.swift

@@ -14,8 +14,7 @@ import Foundation
 import RegexBuilder
 
 /// All the information necessary to replay a sourcektid request.
-@_spi(Testing)
-public struct RequestInfo: Sendable {
+package struct RequestInfo: Sendable {
   /// The JSON request object. Contains the following dynamic placeholders:
   ///  - `$OFFSET`: To be replaced by `offset` before running the request
   ///  - `$FILE`: Will be replaced with a path to the file that contains the reduced source code.
@@ -27,15 +26,12 @@ public struct RequestInfo: Sendable {
   var offset: Int
 
   /// The compiler arguments of the request. Replaces the `$COMPILER_ARGS`placeholder in the request template.
-  @_spi(Testing)
-  public var compilerArgs: [String]
+  package var compilerArgs: [String]
 
   /// The contents of the file that the sourcekitd request operates on.
-  @_spi(Testing)
-  public var fileContents: String
+  package var fileContents: String
 
-  @_spi(Testing)
-  public func request(for file: URL) throws -> String {
+  package func request(for file: URL) throws -> String {
     let encoder = JSONEncoder()
     encoder.outputFormatting = .prettyPrinted
     guard var compilerArgs = String(data: try encoder.encode(compilerArgs), encoding: .utf8) else {
@@ -60,8 +56,7 @@ public struct RequestInfo: Sendable {
     }
     """
 
-  @_spi(Testing)
-  public init(requestTemplate: String, offset: Int, compilerArgs: [String], fileContents: String) {
+  package init(requestTemplate: String, offset: Int, compilerArgs: [String], fileContents: String) {
     self.requestTemplate = requestTemplate
     self.offset = offset
     self.compilerArgs = compilerArgs
@@ -71,8 +66,7 @@ public struct RequestInfo: Sendable {
   /// Creates `RequestInfo` from the contents of the JSON sourcekitd request at `requestPath`.
   ///
   /// The contents of the source file are read from disk.
-  @_spi(Testing)
-  public init(request: String) throws {
+  package init(request: String) throws {
     var requestTemplate = request
 
     // Extract offset

Sources/Diagnose/RunSourcekitdRequestCommand.swift

@@ -18,8 +18,8 @@ import SourceKitD
 
 import struct TSCBasic.AbsolutePath
 
-public struct RunSourceKitdRequestCommand: AsyncParsableCommand {
-  public static let configuration = CommandConfiguration(
+package struct RunSourceKitdRequestCommand: AsyncParsableCommand {
+  package static let configuration = CommandConfiguration(
     commandName: "run-sourcekitd-request",
     abstract: "Run a sourcekitd request and print its result"
   )
@@ -39,9 +39,9 @@ public struct RunSourceKitdRequestCommand: AsyncParsableCommand {
   @Option(help: "line:column override for key.offset")
   var position: String?
 
-  public init() {}
+  package init() {}
 
-  public func run() async throws {
+  package func run() async throws {
     var requestString = try String(contentsOf: URL(fileURLWithPath: sourcekitdRequestPath))
 
     let installPath = try AbsolutePath(validating: Bundle.main.bundlePath)

Sources/Diagnose/SourceKitD+RunWithYaml.swift

@@ -14,8 +14,7 @@ import SourceKitD
 
 extension SourceKitD {
   /// Parse the request from YAML and execute it.
-  @_spi(Testing)
-  public func run(requestYaml: String) async throws -> SKDResponse {
+  package func run(requestYaml: String) async throws -> SKDResponse {
     let request = try requestYaml.cString(using: .utf8)?.withUnsafeBufferPointer { buffer in
       var error: UnsafeMutablePointer<CChar>?
       let req = api.request_create_from_yaml(buffer.baseAddress!, &error)

Sources/Diagnose/SourceKitDRequestExecutor.swift

@@ -18,8 +18,7 @@ import class TSCBasic.Process
 import struct TSCBasic.ProcessResult
 
 /// The different states in which a sourcekitd request can finish.
-@_spi(Testing)
-public enum SourceKitDRequestResult: Sendable {
+package enum SourceKitDRequestResult: Sendable {
   /// The request succeeded.
   case success(response: String)
 
@@ -44,8 +43,7 @@ fileprivate extension String {
 }
 
 /// An executor that can run a sourcekitd request and indicate whether the request reprodes a specified issue.
-@_spi(Testing)
-public protocol SourceKitRequestExecutor {
+package protocol SourceKitRequestExecutor {
   @MainActor func runSourceKitD(request: RequestInfo) async throws -> SourceKitDRequestResult
   @MainActor func runSwiftFrontend(request: RequestInfo) async throws -> SourceKitDRequestResult
 }
@@ -62,8 +60,7 @@ extension SourceKitRequestExecutor {
 }
 
 /// Runs `sourcekit-lsp run-sourcekitd-request` to check if a sourcekit-request crashes.
-@_spi(Testing)
-public class OutOfProcessSourceKitRequestExecutor: SourceKitRequestExecutor {
+package class OutOfProcessSourceKitRequestExecutor: SourceKitRequestExecutor {
   /// The path to `sourcekitd.framework/sourcekitd`.
   private let sourcekitd: URL
 
@@ -80,8 +77,7 @@ public class OutOfProcessSourceKitRequestExecutor: SourceKitRequestExecutor {
   /// considered to reproduce the issue.
   private let reproducerPredicate: NSPredicate?
 
-  @_spi(Testing)
-  public init(sourcekitd: URL, swiftFrontend: URL, reproducerPredicate: NSPredicate?) {
+  package init(sourcekitd: URL, swiftFrontend: URL, reproducerPredicate: NSPredicate?) {
     self.sourcekitd = sourcekitd
     self.swiftFrontend = swiftFrontend
     self.reproducerPredicate = reproducerPredicate
@@ -139,8 +135,7 @@ public class OutOfProcessSourceKitRequestExecutor: SourceKitRequestExecutor {
     }
   }
 
-  @_spi(Testing)
-  public func runSwiftFrontend(request: RequestInfo) async throws -> SourceKitDRequestResult {
+  package func runSwiftFrontend(request: RequestInfo) async throws -> SourceKitDRequestResult {
     try request.fileContents.write(to: temporarySourceFile, atomically: true, encoding: .utf8)
 
     let arguments = request.compilerArgs.replacing(["$FILE"], with: [temporarySourceFile.path])
@@ -152,8 +147,7 @@ public class OutOfProcessSourceKitRequestExecutor: SourceKitRequestExecutor {
     return requestResult(for: result)
   }
 
-  @_spi(Testing)
-  public func runSourceKitD(request: RequestInfo) async throws -> SourceKitDRequestResult {
+  package func runSourceKitD(request: RequestInfo) async throws -> SourceKitDRequestResult {
     try request.fileContents.write(to: temporarySourceFile, atomically: true, encoding: .utf8)
     let requestString = try request.request(for: temporarySourceFile)
     try requestString.write(to: temporaryRequestFile, atomically: true, encoding: .utf8)

Sources/Diagnose/SourceReducer.swift

@@ -20,9 +20,8 @@ import SwiftSyntax
 // MARK: - Entry point
 
 extension RequestInfo {
-  @_spi(Testing)
   @MainActor
-  public func reduceInputFile(
+  package func reduceInputFile(
     using executor: SourceKitRequestExecutor,
     progressUpdate: (_ progress: Double, _ message: String) -> Void
   ) async throws -> RequestInfo {

Sources/Diagnose/Toolchain+SwiftFrontend.swift

@@ -17,8 +17,7 @@ extension Toolchain {
   /// The path to `swift-frontend` in the toolchain, found relative to `swift`.
   ///
   /// - Note: Not discovered as part of the toolchain because `swift-frontend` is only needed in the diagnose commands.
-  @_spi(Testing)
-  public var swiftFrontend: URL? {
+  package var swiftFrontend: URL? {
     return swift?.asURL.deletingLastPathComponent().appendingPathComponent("swift-frontend")
   }
 }

Sources/InProcessClient/LocalConnection.swift

@@ -26,7 +26,7 @@ import LanguageServerProtocol
 /// conn.send(...) // handled by server
 /// conn.close()
 /// ```
-public final class LocalConnection: Connection, Sendable {
+package final class LocalConnection: Connection, Sendable {
   private enum State {
     case ready, started, closed
   }
@@ -46,7 +46,7 @@ public final class LocalConnection: Connection, Sendable {
   /// - Important: Must only be accessed from `queue`
   nonisolated(unsafe) private var handler: MessageHandler? = nil
 
-  public init(name: String) {
+  package init(name: String) {
     self.name = name
   }
 
@@ -58,7 +58,7 @@ public final class LocalConnection: Connection, Sendable {
     }
   }
 
-  public func start(handler: MessageHandler) {
+  package func start(handler: MessageHandler) {
     queue.sync {
       precondition(state == .ready)
       state = .started
@@ -74,7 +74,7 @@ public final class LocalConnection: Connection, Sendable {
     state = .closed
   }
 
-  public func close() {
+  package func close() {
     queue.sync {
       closeAssumingOnQueue()
     }
@@ -87,7 +87,7 @@ public final class LocalConnection: Connection, Sendable {
     }
   }
 
-  public func send<Notification: NotificationType>(_ notification: Notification) {
+  package func send<Notification: NotificationType>(_ notification: Notification) {
     logger.info(
       """
       Sending notification to \(self.name, privacy: .public)
@@ -100,7 +100,7 @@ public final class LocalConnection: Connection, Sendable {
     handler.handle(notification)
   }
 
-  public func send<Request: RequestType>(
+  package func send<Request: RequestType>(
     _ request: Request,
     reply: @Sendable @escaping (LSPResult<Request.Response>) -> Void
   ) -> RequestID {