When using SOURCEKIT_LSP_TEST_PLUGIN_PATHS=RELATIVE_TO_SOURCEKITD infer plugin paths from default testing toolchain

Otherwise, we infer the SourceKit plugin paths from the toolchain when creating a `SourceKitLSPServer` during testing because we don’t override the plugin paths in the SourceKitLSPOptions. But when running `SourceKitDTests`, we pass `pluginPaths: nil`, which would not load any plugins. If both of the tests run in the same process, this causes a fault to get logged because sourcekitd can only loaded once per process and we can’t modify which plugins are loaded after the fact.

Author: ahoppen

Sources/SKTestSupport/IndexedSingleSwiftFileTestProject.swift

@@ -147,7 +147,7 @@ package struct IndexedSingleSwiftFileTestProject {
     }
 
     // Create the test client
-    var options = SourceKitLSPOptions.testDefault()
+    var options = try await SourceKitLSPOptions.testDefault()
     options.indexOrDefault = SourceKitLSPOptions.IndexOptions(
       indexStorePath: try indexURL.filePath,
       indexDatabasePath: try indexDBURL.filePath

Sources/SKTestSupport/MultiFileTestProject.swift

@@ -138,7 +138,7 @@ package class MultiFileTestProject {
     },
     initializationOptions: LSPAny? = nil,
     capabilities: ClientCapabilities = ClientCapabilities(),
-    options: SourceKitLSPOptions = .testDefault(),
+    options: SourceKitLSPOptions? = nil,
     toolchainRegistry: ToolchainRegistry = .forTesting,
     hooks: Hooks = Hooks(),
     enableBackgroundIndexing: Bool = false,

Sources/SKTestSupport/PluginPaths.swift

@@ -11,6 +11,7 @@
 //===----------------------------------------------------------------------===//
 
 import Foundation
+import ToolchainRegistry
 
 #if compiler(>=6)
 package import SourceKitD
@@ -109,8 +110,8 @@ private func pluginPaths(relativeTo base: URL) -> PluginPaths? {
 
 /// Returns the paths from which the SourceKit plugins should be loaded or throws an error if the plugins cannot be
 /// found.
-package var sourceKitPluginPaths: PluginPaths? {
-  get throws {
+package var sourceKitPluginPaths: PluginPaths {
+  get async throws {
     struct PluginLoadingError: Error, CustomStringConvertible {
       let searchBase: URL
       var description: String {
@@ -129,7 +130,12 @@ package var sourceKitPluginPaths: PluginPaths? {
     var base: URL
     if let pluginPaths = ProcessInfo.processInfo.environment["SOURCEKIT_LSP_TEST_PLUGIN_PATHS"] {
       if pluginPaths == "RELATIVE_TO_SOURCEKITD" {
-        return nil
+        let toolchain = await ToolchainRegistry.forTesting.default
+        guard let clientPlugin = toolchain?.sourceKitClientPlugin, let servicePlugin = toolchain?.sourceKitServicePlugin
+        else {
+          throw PluginLoadingError(searchBase: URL(string: "relative-to-sourcekitd://")!)
+        }
+        return PluginPaths(clientPlugin: clientPlugin, servicePlugin: servicePlugin)
       } else {
         base = URL(fileURLWithPath: pluginPaths)
       }

Sources/SKTestSupport/SwiftPMTestProject.swift

@@ -196,7 +196,7 @@ package class SwiftPMTestProject: MultiFileTestProject {
     },
     initializationOptions: LSPAny? = nil,
     capabilities: ClientCapabilities = ClientCapabilities(),
-    options: SourceKitLSPOptions = .testDefault(),
+    options: SourceKitLSPOptions? = nil,
     hooks: Hooks = Hooks(),
     enableBackgroundIndexing: Bool = false,
     usePullDiagnostics: Bool = true,

Sources/SKTestSupport/TestSourceKitLSPClient.swift

@@ -36,11 +36,12 @@ extension SourceKitLSPOptions {
   package static func testDefault(
     backgroundIndexing: Bool = true,
     experimentalFeatures: Set<ExperimentalFeature>? = nil
-  ) -> SourceKitLSPOptions {
+  ) async throws -> SourceKitLSPOptions {
+    let pluginPaths = try await sourceKitPluginPaths
     return SourceKitLSPOptions(
       sourcekitd: SourceKitDOptions(
-        clientPlugin: try! sourceKitPluginPaths?.clientPlugin.filePath,
-        servicePlugin: try! sourceKitPluginPaths?.servicePlugin.filePath
+        clientPlugin: try pluginPaths.clientPlugin.filePath,
+        servicePlugin: try pluginPaths.servicePlugin.filePath
       ),
       backgroundIndexing: backgroundIndexing,
       experimentalFeatures: experimentalFeatures,
@@ -137,7 +138,7 @@ package final class TestSourceKitLSPClient: MessageHandler, Sendable {
   ///     This allows e.g. a `IndexedSingleSwiftFileTestProject` to delete its temporary files when they are no longer
   ///     needed.
   package init(
-    options: SourceKitLSPOptions = .testDefault(),
+    options: SourceKitLSPOptions? = nil,
     hooks: Hooks = Hooks(),
     initialize: Bool = true,
     initializationOptions: LSPAny? = nil,
@@ -149,7 +150,12 @@ package final class TestSourceKitLSPClient: MessageHandler, Sendable {
     preInitialization: ((TestSourceKitLSPClient) -> Void)? = nil,
     cleanUp: @Sendable @escaping () -> Void = {}
   ) async throws {
-    var options = options
+    var options =
+      if let options {
+        options
+      } else {
+        try await SourceKitLSPOptions.testDefault()
+      }
     if let globalModuleCache = try globalModuleCache {
       options.swiftPMOrDefault.swiftCompilerFlags =
         (options.swiftPMOrDefault.swiftCompilerFlags ?? []) + ["-module-cache-path", try globalModuleCache.filePath]

Tests/BuildSystemIntegrationTests/SwiftPMBuildSystemTests.swift

@@ -53,7 +53,7 @@ final class SwiftPMBuildSystemTests: XCTestCase {
         ]
       )
       let packageRoot = tempDir.appendingPathComponent("pkg")
-      let buildSystemSpec = SwiftPMBuildSystem.searchForConfig(in: packageRoot, options: .testDefault())
+      let buildSystemSpec = SwiftPMBuildSystem.searchForConfig(in: packageRoot, options: try await .testDefault())
       XCTAssertNil(buildSystemSpec)
     }
   }
@@ -779,7 +779,9 @@ final class SwiftPMBuildSystemTests: XCTestCase {
         withDestinationURL: URL(fileURLWithPath: tempDir.appendingPathComponent("pkg_real").filePath)
       )
 
-      let buildSystemSpec = try XCTUnwrap(SwiftPMBuildSystem.searchForConfig(in: packageRoot, options: .testDefault()))
+      let buildSystemSpec = try unwrap(
+        SwiftPMBuildSystem.searchForConfig(in: packageRoot, options: await .testDefault())
+      )
       let buildSystemManager = await BuildSystemManager(
         buildSystemSpec: buildSystemSpec,
         toolchainRegistry: .forTesting,
@@ -864,7 +866,9 @@ final class SwiftPMBuildSystemTests: XCTestCase {
         withDestinationURL: URL(fileURLWithPath: tempDir.appendingPathComponent("pkg_real").filePath)
       )
 
-      let buildSystemSpec = try XCTUnwrap(SwiftPMBuildSystem.searchForConfig(in: symlinkRoot, options: .testDefault()))
+      let buildSystemSpec = try unwrap(
+        SwiftPMBuildSystem.searchForConfig(in: symlinkRoot, options: await .testDefault())
+      )
       let buildSystemManager = await BuildSystemManager(
         buildSystemSpec: buildSystemSpec,
         toolchainRegistry: .forTesting,
@@ -961,7 +965,7 @@ final class SwiftPMBuildSystemTests: XCTestCase {
         .appendingPathComponent("Sources")
         .appendingPathComponent("lib")
 
-      let buildSystemSpec = SwiftPMBuildSystem.searchForConfig(in: workspaceRoot, options: .testDefault())
+      let buildSystemSpec = SwiftPMBuildSystem.searchForConfig(in: workspaceRoot, options: try await .testDefault())
       XCTAssertNil(buildSystemSpec)
     }
   }

Tests/SourceKitLSPTests/BackgroundIndexingTests.swift

@@ -969,7 +969,7 @@ final class BackgroundIndexingTests: XCTestCase {
   }
 
   func testUseBuildFlagsDuringPreparation() async throws {
-    var options = SourceKitLSPOptions.testDefault()
+    var options = try await SourceKitLSPOptions.testDefault()
     options.swiftPMOrDefault.swiftCompilerFlags = ["-D", "MY_FLAG"]
     let project = try await SwiftPMTestProject(
       files: [
@@ -1016,7 +1016,7 @@ final class BackgroundIndexingTests: XCTestCase {
   func testUseSwiftSDKFlagsDuringPreparation() async throws {
     try await SkipUnless.canSwiftPMCompileForIOS()
 
-    var options = SourceKitLSPOptions.testDefault()
+    var options = try await SourceKitLSPOptions.testDefault()
     options.swiftPMOrDefault.swiftSDK = "arm64-apple-ios"
     let project = try await SwiftPMTestProject(
       files: [
@@ -1108,7 +1108,7 @@ final class BackgroundIndexingTests: XCTestCase {
   }
 
   func testCrossModuleFunctionalityEvenIfLowLevelModuleHasErrors() async throws {
-    var options = SourceKitLSPOptions.testDefault()
+    var options = try await SourceKitLSPOptions.testDefault()
     options.backgroundPreparationMode = .enabled
     let project = try await SwiftPMTestProject(
       files: [
@@ -1154,7 +1154,7 @@ final class BackgroundIndexingTests: XCTestCase {
   }
 
   func testCrossModuleFunctionalityWithPreparationNoSkipping() async throws {
-    var options = SourceKitLSPOptions.testDefault()
+    var options = try await SourceKitLSPOptions.testDefault()
     options.backgroundPreparationMode = .noLazy
     let project = try await SwiftPMTestProject(
       files: [
@@ -1438,7 +1438,7 @@ final class BackgroundIndexingTests: XCTestCase {
   func testCancelIndexing() async throws {
     try SkipUnless.longTestsEnabled()
 
-    var options = SourceKitLSPOptions.testDefault()
+    var options = try await SourceKitLSPOptions.testDefault()
     options.backgroundPreparationMode = .enabled
     options.indexOrDefault.updateIndexStoreTimeout = 1 /* second */
 

Tests/SourceKitLSPTests/BuildSystemTests.swift

@@ -67,14 +67,14 @@ final class BuildSystemTests: XCTestCase {
         configPath: URL(fileURLWithPath: "/")
       ),
       toolchainRegistry: .forTesting,
-      options: .testDefault(),
+      options: try .testDefault(),
       connectionToClient: DummyBuildSystemManagerConnectionToClient(),
       buildSystemHooks: BuildSystemHooks()
     )
     buildSystem = try await unwrap(buildSystemInjector.testBuildSystem)
 
     self.workspace = await Workspace.forTesting(
-      options: SourceKitLSPOptions.testDefault(),
+      options: try .testDefault(),
       testHooks: Hooks(),
       buildSystemManager: buildSystemManager,
       indexTaskScheduler: .forTesting

Tests/SourceKitLSPTests/LocalSwiftTests.swift

@@ -1425,7 +1425,7 @@ final class LocalSwiftTests: XCTestCase {
   func testSourceKitdTimeout() async throws {
     try SkipUnless.longTestsEnabled()
 
-    var options = SourceKitLSPOptions.testDefault()
+    var options = try await SourceKitLSPOptions.testDefault()
     // This is how long we wait until implicitly cancelling the first diagnostics request.
     // It needs to be long enough so we can compute diagnostics for the second requests.
     // 1s is not sufficient on Windows for that.

Tests/SwiftSourceKitPluginTests/PluginSwiftPMTestProject.swift

@@ -28,7 +28,7 @@ final class PluginSwiftPMTestProject {
 
   private var _buildSystemManager: BuildSystemManager?
   private var buildSystemManager: BuildSystemManager {
-    get async {
+    get async throws {
       if let _buildSystemManager {
         return _buildSystemManager
       }
@@ -39,7 +39,7 @@ final class PluginSwiftPMTestProject {
           configPath: scratchDirectory.appendingPathComponent("Package.swift")
         ),
         toolchainRegistry: .forTesting,
-        options: .testDefault(backgroundIndexing: false),
+        options: try .testDefault(backgroundIndexing: false),
         connectionToClient: DummyBuildSystemManagerConnectionToClient(),
         buildSystemHooks: BuildSystemHooks()
       )
@@ -98,8 +98,8 @@ final class PluginSwiftPMTestProject {
   }
 
   package func compilerArguments(for fileName: String) async throws -> [String] {
-    await buildSystemManager.waitForUpToDateBuildGraph()
-    let buildSettings = await buildSystemManager.buildSettingsInferredFromMainFile(
+    try await buildSystemManager.waitForUpToDateBuildGraph()
+    let buildSettings = try await buildSystemManager.buildSettingsInferredFromMainFile(
       for: try uri(for: fileName),
       language: .swift,
       fallbackAfterTimeout: false