Allow configuring of SourceKit-LSP’s options using configuration files

Documentation/Configuration File.md

@@ -0,0 +1,38 @@
+# Configuration File
+
+`.sourcekit-lsp/config.json` configuration files can be used to modify the behavior of SourceKit-LSP in various ways. The following locations are checked. Settings in later configuration files override settings in earlier configuration files
+- `~/.sourcekit-lsp/config.json`
+- On macOS: `~/Library/Application Support/org.swift.sourcekit-lsp/config.json` from the various `Library` folders on the system
+- If the `XDG_CONFIG_HOME` environment variable is set: `$XDG_CONFIG_HOME/org.swift.sourcekit-lsp/config.json`
+- A `.sourcekit-lsp/config.json` file in a workspace’s root
+
+The structure of the file is currently not guaranteed to be stable. Options may be removed or renamed.
+
+## Structure
+
+`config.json` is a JSON file with the following structure. All keys are optional and unknown keys are ignored.
+
+- `swiftPM`: Dictionary with the following keys, defining options for SwiftPM workspaces
+  - `configuration: "debug"|"release"`: The configuration to build the project for during background indexing and the configuration whose build folder should be used for Swift modules if background indexing is disabled
+  - `scratchPath: string`: Build artifacts directory path. If nil, the build system may choose a default value
+  - `cCompilerFlags: string[]`: Extra arguments passed to the compiler for C files
+  - `cxxCompilerFlags: string[]`: Extra arguments passed to the compiler for C++ files
+  - `swiftCompilerFlags: string[]`: Extra arguments passed to the compiler for Swift files
+  - `linkerFlags: string[]`: Extra arguments passed to the linker
+- `compilationDatabase`: Dictionary with the following keys, defining options for workspaces with a compilation database
+  - `searchPaths: string[]`: Additional paths to search for a compilation database, relative to a workspace root.
+- `fallbackBuildSystem`: Dictionary with the following keys, defining options for files that aren't managed by any build system
+  - `cCompilerFlags: string[]`: Extra arguments passed to the compiler for C files
+  - `cxxCompilerFlags: string[]`: Extra arguments passed to the compiler for C++ files
+  - `swiftCompilerFlags: string[]`: Extra arguments passed to the compiler for Swift files
+- `clangdOptions: string[]`: Extra command line arguments passed to `clangd` when launching it
+- `index`: Dictionary with the following keys, defining options related to indexing
+    - `indexStorePath: string`: Directory in which a separate compilation stores the index store. By default, inferred from the build system.
+    - `indexDatabasePath: string`: Directory in which the indexstore-db should be stored. By default, inferred from the build system.
+    - `indexPrefixMap: [string: string]`: Path remappings for remapping index data for local use.
+    - `maxCoresPercentageToUseForBackgroundIndexing: double`: A hint indicating how many cores background indexing should use at most (value between 0 and 1). Background indexing is not required to honor this setting
+    - `updateIndexStoreTimeout: int`: Number of seconds to wait for an update index store task to finish before killing it.
+- `defaultWorkspaceType: "buildserver"|"compdb"|"swiftpm"`: Overrides workspace type selection logic.
+- `generatedFilesPath: string`: Directory in which generated interfaces and macro expansions should be stored.
+- `experimentalFeatures: string[]`: Experimental features to enable
+- `swiftPublishDiagnosticsDebounce`: The time that `SwiftLanguageService` should wait after an edit before starting to compute diagnostics and sending a `PublishDiagnosticsNotification`.

Documentation/LSP Extensions.md

@@ -73,102 +73,6 @@ Added case
 identifier = 'identifier'
 ```
 
-## `WorkspaceFolder`
-
-Added field:
-
-```ts
-/**
- * Build settings that should be used for this workspace.
- *
- * For arguments that have a single value (like the build configuration), this takes precedence over the global
- * options set when launching sourcekit-lsp. For all other options, the values specified in the workspace-specific
- * build setup are appended to the global options.
- */
-var buildSetup?: WorkspaceBuildSetup
-```
-
-with
-
-```ts
-/**
- * The configuration to build a workspace in.
- */
-export enum BuildConfiguration {
-  case debug = 'debug'
-  case release = 'release'
-}
-
-/**
- * The type of workspace; default workspace type selection logic can be overridden.
- */
-export enum WorkspaceType {
-  buildServer = 'buildServer'
-  compilationDatabase = 'compilationDatabase'
-  swiftPM = 'swiftPM'
-}
-
-/// Build settings that should be used for a workspace.
-interface WorkspaceBuildSetup {
-  /**
-   * The configuration that the workspace should be built in.
-   */
-  buildConfiguration?: BuildConfiguration
-
-  /**
-   * The default workspace type to use for this workspace.
-   */
-  defaultWorkspaceType?: WorkspaceType
-
-  /**
-   * The build directory for the workspace.
-   */
-  scratchPath?: DocumentURI
-
-  /**
-   * Arguments to be passed to any C compiler invocations.
-   */
-  cFlags?: string[]
-
-  /**
-   * Arguments to be passed to any C++ compiler invocations.
-   */
-  cxxFlags?: string[]
-
-  /**
-   * Arguments to be passed to any linker invocations.
-   */
-  linkerFlags?: string[]
-
-  /**
-   * Arguments to be passed to any Swift compiler invocations.
-   */
-  swiftFlags?: string[]
-}
-```
-
-## `textDocument/completion`
-
-Added field:
-
-```ts
-/**
- * Options to control code completion behavior in Swift
- */
-sourcekitlspOptions?: SKCompletionOptions
-```
-
-with
-
-```ts
-interface SKCompletionOptions {
-  /**
-   * The maximum number of completion results to return, or `null` for unlimited.
-   */
-  maxResults?: int
-}
-```
-
 ## `textDocument/interface`
 
 New request that request a textual interface of a module to display in the IDE. Used internally within SourceKit-LSP

Sources/Diagnose/IndexCommand.swift

@@ -82,9 +82,7 @@ public struct IndexCommand: AsyncParsableCommand {
   public init() {}
 
   public func run() async throws {
-    var serverOptions = SourceKitLSPServer.Options()
-    serverOptions.experimentalFeatures = Set(experimentalFeatures)
-    serverOptions.experimentalFeatures.insert(.backgroundIndexing)
+    let options = SourceKitLSPOptions(experimentalFeatures: Set(experimentalFeatures).union([.backgroundIndexing]))
 
     let installPath =
       if let toolchainOverride, let toolchain = Toolchain(try AbsolutePath(validating: toolchainOverride)) {
@@ -96,7 +94,7 @@ public struct IndexCommand: AsyncParsableCommand {
     let messageHandler = IndexLogMessageHandler()
     let inProcessClient = try await InProcessSourceKitLSPClient(
       toolchainRegistry: ToolchainRegistry(installPath: installPath),
-      serverOptions: serverOptions,
+      options: options,
       workspaceFolders: [WorkspaceFolder(uri: DocumentURI(URL(fileURLWithPath: project)))],
       messageHandler: messageHandler
     )

Sources/InProcessClient/InProcessSourceKitLSPClient.swift

@@ -26,7 +26,8 @@ public final class InProcessSourceKitLSPClient: Sendable {
   /// `messageHandler` handles notifications and requests sent from the SourceKit-LSP server to the client.
   public init(
     toolchainRegistry: ToolchainRegistry,
-    serverOptions: SourceKitLSPServer.Options = SourceKitLSPServer.Options(),
+    options: SourceKitLSPOptions = SourceKitLSPOptions(),
+    testHooks: TestHooks = TestHooks(),
     capabilities: ClientCapabilities = ClientCapabilities(),
     workspaceFolders: [WorkspaceFolder],
     messageHandler: any MessageHandler
@@ -35,7 +36,8 @@ public final class InProcessSourceKitLSPClient: Sendable {
     self.server = SourceKitLSPServer(
       client: serverToClientConnection,
       toolchainRegistry: toolchainRegistry,
-      options: serverOptions,
+      options: options,
+      testHooks: testHooks,
       onExit: {
         serverToClientConnection.close()
       }

Sources/LanguageServerProtocol/CMakeLists.txt

@@ -124,7 +124,6 @@ add_library(LanguageServerProtocol STATIC
   SupportTypes/SemanticTokens.swift
   SupportTypes/SemanticTokenTypes.swift
   SupportTypes/ServerCapabilities.swift
-  SupportTypes/SKCompletionOptions.swift
   SupportTypes/StringOrMarkupContent.swift
   SupportTypes/SymbolKind.swift
   SupportTypes/TestItem.swift

Sources/LanguageServerProtocol/Requests/CompletionRequest.swift

@@ -23,7 +23,6 @@
 ///   - textDocument: The document to perform completion in.
 ///   - position: The location to perform completion at.
 ///   - context: Optional code-completion context.
-///   - sourcekitlspOptions: **(LSP Extension)** code-completion options for sourcekit-lsp.
 ///
 /// - Returns: A list of completion items to complete the code at the given position.
 public struct CompletionRequest: TextDocumentRequest, Hashable {
@@ -36,18 +35,14 @@ public struct CompletionRequest: TextDocumentRequest, Hashable {
 
   public var context: CompletionContext?
 
-  public var sourcekitlspOptions: SKCompletionOptions?
-
   public init(
     textDocument: TextDocumentIdentifier,
     position: Position,
-    context: CompletionContext? = nil,
-    sourcekitlspOptions: SKCompletionOptions? = nil
+    context: CompletionContext? = nil
   ) {
     self.textDocument = textDocument
     self.position = position
     self.context = context
-    self.sourcekitlspOptions = sourcekitlspOptions
   }
 }
 

Sources/LanguageServerProtocol/Requests/PollIndexRequest.swift

@@ -12,9 +12,6 @@
 
 /// Poll the index for unit changes and wait for them to be registered.
 /// **LSP Extension, For Testing**.
-///
-/// Users of PollIndex should set `"initializationOptions": { "listenToUnitEvents": false }` during
-/// the `initialize` request.
 public struct PollIndexRequest: RequestType {
   public static let method: String = "workspace/_pollIndex"
   public typealias Response = VoidResponse

Sources/LanguageServerProtocol/SupportTypes/WorkspaceFolder.swift

@@ -10,65 +10,6 @@
 //
 //===----------------------------------------------------------------------===//
 
-/// The configuration to build a workspace in.
-///
-/// **(LSP Extension)**
-public enum BuildConfiguration: Hashable, Codable, Sendable {
-  case debug
-  case release
-}
-
-/// The type of workspace; default workspace type selection logic can be overridden.
-///
-/// **(LSP Extension)**
-public enum WorkspaceType: Hashable, Codable, Sendable {
-  case buildServer, compilationDatabase, swiftPM
-}
-
-/// Build settings that should be used for a workspace.
-///
-/// **(LSP Extension)**
-public struct WorkspaceBuildSetup: Hashable, Codable, Sendable {
-  /// The configuration that the workspace should be built in.
-  public let buildConfiguration: BuildConfiguration?
-
-  /// The default workspace type to use for this workspace.
-  public let defaultWorkspaceType: WorkspaceType?
-
-  /// The build directory for the workspace.
-  public let scratchPath: DocumentURI?
-
-  /// Arguments to be passed to any C compiler invocations.
-  public let cFlags: [String]?
-
-  /// Arguments to be passed to any C++ compiler invocations.
-  public let cxxFlags: [String]?
-
-  /// Arguments to be passed to any linker invocations.
-  public let linkerFlags: [String]?
-
-  /// Arguments to be passed to any Swift compiler invocations.
-  public let swiftFlags: [String]?
-
-  public init(
-    buildConfiguration: BuildConfiguration? = nil,
-    defaultWorkspaceType: WorkspaceType? = nil,
-    scratchPath: DocumentURI? = nil,
-    cFlags: [String]? = nil,
-    cxxFlags: [String]? = nil,
-    linkerFlags: [String]? = nil,
-    swiftFlags: [String]? = nil
-  ) {
-    self.buildConfiguration = buildConfiguration
-    self.defaultWorkspaceType = defaultWorkspaceType
-    self.scratchPath = scratchPath
-    self.cFlags = cFlags
-    self.cxxFlags = cxxFlags
-    self.linkerFlags = linkerFlags
-    self.swiftFlags = swiftFlags
-  }
-}
-
 /// Unique identifier for a document.
 public struct WorkspaceFolder: ResponseType, Hashable, Codable, Sendable {
 
@@ -78,27 +19,13 @@ public struct WorkspaceFolder: ResponseType, Hashable, Codable, Sendable {
   /// The name of the workspace (default: basename of url).
   public var name: String
 
-  /// Build settings that should be used for this workspace.
-  ///
-  /// For arguments that have a single value (like the build configuration), this takes precedence over the global
-  /// options set when launching sourcekit-lsp. For all other options, the values specified in the workspace-specific
-  /// build setup are appended to the global options.
-  ///
-  /// **(LSP Extension)**
-  public var buildSetup: WorkspaceBuildSetup?
-
-  public init(
-    uri: DocumentURI,
-    name: String? = nil,
-    buildSetup: WorkspaceBuildSetup? = nil
-  ) {
+  public init(uri: DocumentURI, name: String? = nil) {
     self.uri = uri
 
     self.name = name ?? uri.fileURL?.lastPathComponent ?? "unknown_workspace"
 
     if self.name.isEmpty {
       self.name = "unknown_workspace"
     }
-    self.buildSetup = buildSetup
   }
 }

Sources/SKCore/BuildConfiguration.swift

@@ -10,7 +10,7 @@
 //
 //===----------------------------------------------------------------------===//
 
-public enum BuildConfiguration: String, Sendable {
+public enum BuildConfiguration: String, Codable, Sendable {
   case debug
   case release
 }