Allow workspace options to affect build system search

There were a few places that options only took place *after* determining
a build system, even though we have multiple that impact the search (eg.
`defaultBuildSystem` and `searchPaths`).

Do not search up the directory tree when searching for a build system
for a workspace. Only allow this for implicit workspaces (created when
no existing workspace can handle a file) and only up to any existing
workspace roots.

Author: bnbarham

Documentation/Configuration File.md

@@ -43,7 +43,7 @@ The structure of the file is currently not guaranteed to be stable. Options may
   - `logLevel: "debug"|"info"|"default"|"error"|"fault"`: The level from which one onwards log messages should be written.
   - `privacyLevel: "public"|"private"|"sensitive"`: Whether potentially sensitive information should be redacted. Default is `public`, which redacts potentially sensitive information.
   - `inputMirrorDirectory: string`: Write all input received by SourceKit-LSP on stdin to a file in this directory. Useful to record and replay an entire SourceKit-LSP session.
-- `defaultWorkspaceType: "buildserver"|"compdb"|"swiftpm"`: Overrides workspace type selection logic.
+- `defaultWorkspaceType: "swiftPM"|"compilationDatabase"|"buildServer"`: Overrides workspace type selection logic.
 - `generatedFilesPath: string`: Directory in which generated interfaces and macro expansions should be stored.
 - `backgroundIndexing: bool`: Explicitly enable or disable background indexing.
 - `backgroundPreparationMode: "build"|"noLazy"|"enabled"`: Determines how background indexing should prepare a target. Possible values are:

Sources/BuildSystemIntegration/BuildSystemManager.swift

@@ -203,9 +203,6 @@ private extension BuildSystemSpec {
       ) { connectionToSourceKitLSP in
         CompilationDatabaseBuildSystem(
           projectRoot: projectRoot,
-          searchPaths: (options.compilationDatabaseOrDefault.searchPaths ?? []).compactMap {
-            try? RelativePath(validating: $0)
-          },
           connectionToSourceKitLSP: connectionToSourceKitLSP
         )
       }

Sources/BuildSystemIntegration/CompilationDatabase.swift

@@ -116,33 +116,19 @@ package protocol CompilationDatabase {
   var sourceItems: [SourceItem] { get }
 }
 
-/// Loads the compilation database located in `directory`, if one can be found in `additionalSearchPaths` or in the default search paths of "." and "build".
+/// Loads the compilation database located in `directory`.
 package func tryLoadCompilationDatabase(
-  directory: URL,
-  additionalSearchPaths: [RelativePath] = []
+  directory: URL
 ) -> CompilationDatabase? {
-  let searchPaths =
-    additionalSearchPaths + [
-      // These default search paths match the behavior of `clangd`
-      try! RelativePath(validating: "."),
-      try! RelativePath(validating: "build"),
-    ]
-  return
-    searchPaths
-    .lazy
-    .map { directory.appending($0) }
-    .compactMap { searchPath in
-      orLog("Failed to load compilation database") { () -> CompilationDatabase? in
-        if let compDb = try JSONCompilationDatabase(directory: searchPath) {
-          return compDb
-        }
-        if let compDb = try FixedCompilationDatabase(directory: searchPath) {
-          return compDb
-        }
-        return nil
-      }
+  orLog("Failed to load compilation database") { () -> CompilationDatabase? in
+    if let jsonDb = try JSONCompilationDatabase(directory: directory) {
+      return jsonDb
+    }
+    if let fixedDb = try FixedCompilationDatabase(directory: directory) {
+      return fixedDb
     }
-    .first
+    return nil
+  }
 }
 
 /// Fixed clang-compatible compilation database (compile_flags.txt).
@@ -156,6 +142,8 @@ package func tryLoadCompilationDatabase(
 ///
 /// See https://clang.llvm.org/docs/JSONCompilationDatabase.html under Alternatives
 package struct FixedCompilationDatabase: CompilationDatabase, Equatable {
+  package static let dbName: String = "compile_flags.txt"
+
   private let fixedArgs: [String]
   private let directory: String
 
@@ -172,7 +160,7 @@ package struct FixedCompilationDatabase: CompilationDatabase, Equatable {
   /// Loads the compilation database located in `directory`, if any.
   /// - Returns: `nil` if `compile_flags.txt` was not found
   package init?(directory: URL) throws {
-    let path = directory.appendingPathComponent("compile_flags.txt")
+    let path = directory.appendingPathComponent(Self.dbName)
     try self.init(file: path)
   }
 
@@ -212,6 +200,8 @@ package struct FixedCompilationDatabase: CompilationDatabase, Equatable {
 ///
 /// See https://clang.llvm.org/docs/JSONCompilationDatabase.html
 package struct JSONCompilationDatabase: CompilationDatabase, Equatable, Codable {
+  package static let dbName: String = "compile_commands.json"
+
   private var pathToCommands: [DocumentURI: [Int]] = [:]
   private var commands: [CompilationDatabaseCompileCommand] = []
 
@@ -232,7 +222,7 @@ package struct JSONCompilationDatabase: CompilationDatabase, Equatable, Codable
   ///
   /// - Returns: `nil` if `compile_commands.json` was not found
   package init?(directory: URL) throws {
-    let path = directory.appendingPathComponent("compile_commands.json")
+    let path = directory.appendingPathComponent(Self.dbName)
     try self.init(file: path)
   }
 

Sources/BuildSystemIntegration/CompilationDatabaseBuildSystem.swift

@@ -62,10 +62,29 @@ fileprivate enum Cachable<Value> {
 /// one compilation database, located at the project root.
 package actor CompilationDatabaseBuildSystem: BuiltInBuildSystem {
   static package func projectRoot(for workspaceFolder: URL, options: SourceKitLSPOptions) -> URL? {
-    if tryLoadCompilationDatabase(directory: workspaceFolder) != nil {
-      return workspaceFolder
-    }
-    return nil
+    let searchPaths =
+      (options.compilationDatabaseOrDefault.searchPaths ?? []).compactMap {
+        try? RelativePath(validating: $0)
+      } + [
+        // These default search paths match the behavior of `clangd`
+        try! RelativePath(validating: "."),
+        try! RelativePath(validating: "build"),
+      ]
+
+    return
+      searchPaths
+      .lazy
+      .compactMap({ searchPath in
+        let path = workspaceFolder.appending(searchPath)
+        if FileManager.default.isFile(at: path.appendingPathComponent(JSONCompilationDatabase.dbName))
+          || FileManager.default.isFile(at: path.appendingPathComponent(FixedCompilationDatabase.dbName))
+        {
+          return path
+        }
+
+        return nil
+      })
+      .first
   }
 
   /// The compilation database.
@@ -78,7 +97,6 @@ package actor CompilationDatabaseBuildSystem: BuiltInBuildSystem {
   }
 
   private let connectionToSourceKitLSP: any Connection
-  private let searchPaths: [RelativePath]
 
   package let projectRoot: URL
 
@@ -119,13 +137,11 @@ package actor CompilationDatabaseBuildSystem: BuiltInBuildSystem {
 
   package init?(
     projectRoot: URL,
-    searchPaths: [RelativePath],
     connectionToSourceKitLSP: any Connection
   ) {
     self.projectRoot = projectRoot
-    self.searchPaths = searchPaths
     self.connectionToSourceKitLSP = connectionToSourceKitLSP
-    if let compdb = tryLoadCompilationDatabase(directory: projectRoot, additionalSearchPaths: searchPaths) {
+    if let compdb = tryLoadCompilationDatabase(directory: projectRoot) {
       self.compdb = compdb
     } else {
       return nil
@@ -182,7 +198,7 @@ package actor CompilationDatabaseBuildSystem: BuiltInBuildSystem {
 
   private func fileEventShouldTriggerCompilationDatabaseReload(event: FileEvent) -> Bool {
     switch event.uri.fileURL?.lastPathComponent {
-    case "compile_commands.json", "compile_flags.txt":
+    case JSONCompilationDatabase.dbName, FixedCompilationDatabase.dbName:
       return true
     default:
       return false
@@ -192,8 +208,7 @@ package actor CompilationDatabaseBuildSystem: BuiltInBuildSystem {
   /// The compilation database has been changed on disk.
   /// Reload it and notify the delegate about build setting changes.
   private func reloadCompilationDatabase() {
-    self.compdb = tryLoadCompilationDatabase(directory: projectRoot, additionalSearchPaths: searchPaths)
-
+    self.compdb = tryLoadCompilationDatabase(directory: projectRoot)
     connectionToSourceKitLSP.send(OnBuildTargetDidChangeNotification(changes: nil))
   }
 }

Sources/BuildSystemIntegration/DetermineBuildSystem.swift

@@ -31,11 +31,13 @@ import struct TSCBasic.AbsolutePath
 #endif
 
 /// Determine which build system should be started to handle the given workspace folder and at which folder that build
-/// system's project root is (see `BuiltInBuildSystem.projectRoot(for:options:)`).
+/// system's project root is (see `BuiltInBuildSystem.projectRoot(for:options:)`). `onlyConsiderRoot` controls whether
+/// paths outside the root should be considered (eg. configuration files in the user's home directory).
 ///
 /// Returns `nil` if no build system can handle this workspace folder.
 package func determineBuildSystem(
   forWorkspaceFolder workspaceFolder: DocumentURI,
+  onlyConsiderRoot: Bool,
   options: SourceKitLSPOptions
 ) -> BuildSystemSpec? {
   var buildSystemPreference: [WorkspaceType] = [
@@ -51,7 +53,11 @@ package func determineBuildSystem(
   for buildSystemType in buildSystemPreference {
     switch buildSystemType {
     case .buildServer:
-      if let projectRoot = ExternalBuildSystemAdapter.projectRoot(for: workspaceFolderUrl, options: options) {
+      if let projectRoot = ExternalBuildSystemAdapter.projectRoot(
+        for: workspaceFolderUrl,
+        onlyConsiderRoot: onlyConsiderRoot,
+        options: options
+      ) {
         return BuildSystemSpec(kind: .buildServer, projectRoot: projectRoot)
       }
     case .compilationDatabase:

Sources/BuildSystemIntegration/ExternalBuildSystemAdapter.swift

@@ -99,8 +99,12 @@ actor ExternalBuildSystemAdapter {
   /// Used to delay restarting in case of a crash loop.
   private var lastRestart: Date?
 
-  static package func projectRoot(for workspaceFolder: URL, options: SourceKitLSPOptions) -> URL? {
-    guard getConfigPath(for: workspaceFolder) != nil else {
+  static package func projectRoot(
+    for workspaceFolder: URL,
+    onlyConsiderRoot: Bool,
+    options: SourceKitLSPOptions
+  ) -> URL? {
+    guard getConfigPath(for: workspaceFolder, onlyConsiderRoot: onlyConsiderRoot) != nil else {
       return nil
     }
     return workspaceFolder
@@ -187,38 +191,40 @@ actor ExternalBuildSystemAdapter {
     ).connection
   }
 
-  private static func getConfigPath(for workspaceFolder: URL? = nil) -> URL? {
+  private static func getConfigPath(for workspaceFolder: URL? = nil, onlyConsiderRoot: Bool = false) -> URL? {
     var buildServerConfigLocations: [URL?] = []
     if let workspaceFolder = workspaceFolder {
       buildServerConfigLocations.append(workspaceFolder.appendingPathComponent(".bsp"))
     }
 
-    #if os(Windows)
-    if let localAppData = ProcessInfo.processInfo.environment["LOCALAPPDATA"] {
-      buildServerConfigLocations.append(URL(fileURLWithPath: localAppData).appendingPathComponent("bsp"))
-    }
-    if let programData = ProcessInfo.processInfo.environment["PROGRAMDATA"] {
-      buildServerConfigLocations.append(URL(fileURLWithPath: programData).appendingPathComponent("bsp"))
-    }
-    #else
-    if let xdgDataHome = ProcessInfo.processInfo.environment["XDG_DATA_HOME"] {
-      buildServerConfigLocations.append(URL(fileURLWithPath: xdgDataHome).appendingPathComponent("bsp"))
-    }
+    if !onlyConsiderRoot {
+      #if os(Windows)
+      if let localAppData = ProcessInfo.processInfo.environment["LOCALAPPDATA"] {
+        buildServerConfigLocations.append(URL(fileURLWithPath: localAppData).appendingPathComponent("bsp"))
+      }
+      if let programData = ProcessInfo.processInfo.environment["PROGRAMDATA"] {
+        buildServerConfigLocations.append(URL(fileURLWithPath: programData).appendingPathComponent("bsp"))
+      }
+      #else
+      if let xdgDataHome = ProcessInfo.processInfo.environment["XDG_DATA_HOME"] {
+        buildServerConfigLocations.append(URL(fileURLWithPath: xdgDataHome).appendingPathComponent("bsp"))
+      }
 
-    if let libraryUrl = FileManager.default.urls(for: .applicationSupportDirectory, in: .userDomainMask).first {
-      buildServerConfigLocations.append(libraryUrl.appendingPathComponent("bsp"))
-    }
+      if let libraryUrl = FileManager.default.urls(for: .applicationSupportDirectory, in: .userDomainMask).first {
+        buildServerConfigLocations.append(libraryUrl.appendingPathComponent("bsp"))
+      }
 
-    if let xdgDataDirs = ProcessInfo.processInfo.environment["XDG_DATA_DIRS"] {
-      buildServerConfigLocations += xdgDataDirs.split(separator: ":").map { xdgDataDir in
-        URL(fileURLWithPath: String(xdgDataDir)).appendingPathComponent("bsp")
+      if let xdgDataDirs = ProcessInfo.processInfo.environment["XDG_DATA_DIRS"] {
+        buildServerConfigLocations += xdgDataDirs.split(separator: ":").map { xdgDataDir in
+          URL(fileURLWithPath: String(xdgDataDir)).appendingPathComponent("bsp")
+        }
       }
-    }
 
-    if let libraryUrl = FileManager.default.urls(for: .applicationSupportDirectory, in: .systemDomainMask).first {
-      buildServerConfigLocations.append(libraryUrl.appendingPathComponent("bsp"))
+      if let libraryUrl = FileManager.default.urls(for: .applicationSupportDirectory, in: .systemDomainMask).first {
+        buildServerConfigLocations.append(libraryUrl.appendingPathComponent("bsp"))
+      }
+      #endif
     }
-    #endif
 
     for case let buildServerConfigLocation? in buildServerConfigLocations {
       let jsonFiles =

Sources/BuildSystemIntegration/SwiftPMBuildSystem.swift

@@ -227,20 +227,15 @@ package actor SwiftPMBuildSystem: BuiltInBuildSystem {
   private var targetDependencies: [BuildTargetIdentifier: Set<BuildTargetIdentifier>] = [:]
 
   static package func projectRoot(for path: URL, options: SourceKitLSPOptions) -> URL? {
-    guard var path = orLog("Getting realpath for project root", { try path.realpath }) else {
+    guard let path = orLog("Getting realpath for project root", { try path.realpath }) else {
       return nil
     }
-    while true {
-      let packagePath = path.appendingPathComponent("Package.swift")
-      if (try? String(contentsOf: packagePath, encoding: .utf8))?.contains("PackageDescription") ?? false {
-        return path
-      }
 
-      if (try? AbsolutePath(validating: path.filePath))?.isRoot ?? true {
-        break
-      }
-      path.deleteLastPathComponent()
+    let packagePath = path.appendingPathComponent("Package.swift")
+    if (try? String(contentsOf: packagePath, encoding: .utf8))?.contains("PackageDescription") ?? false {
+      return path
     }
+
     return nil
   }
 

Sources/SKOptions/SourceKitLSPOptions.swift

@@ -280,7 +280,7 @@ public struct SourceKitLSPOptions: Sendable, Codable, Equatable {
     set { logging = newValue }
   }
 
-  /// Default workspace type (buildserver|compdb|swiftpm). Overrides workspace type selection logic.
+  /// Default workspace type (swiftPM|compilationDatabase|buildServer). Overrides workspace type selection logic.
   public var defaultWorkspaceType: WorkspaceType?
   public var generatedFilesPath: String?
 
@@ -444,6 +444,17 @@ public struct SourceKitLSPOptions: Sendable, Codable, Equatable {
     )
   }
 
+  public static func merging(base: SourceKitLSPOptions, workspaceFolder: DocumentURI) -> SourceKitLSPOptions {
+    return SourceKitLSPOptions.merging(
+      base: base,
+      override: SourceKitLSPOptions(
+        path: workspaceFolder.fileURL?
+          .appendingPathComponent(".sourcekit-lsp")
+          .appendingPathComponent("config.json")
+      )
+    )
+  }
+
   public var generatedFilesAbsolutePath: URL {
     if let generatedFilesPath {
       return URL(fileURLWithPath: generatedFilesPath)

Sources/SKTestSupport/IndexedSingleSwiftFileTestProject.swift

@@ -133,7 +133,7 @@ package struct IndexedSingleSwiftFileTestProject {
     let encoder = JSONEncoder()
     encoder.outputFormatting = .prettyPrinted
     try encoder.encode(compilationDatabase).write(
-      to: testWorkspaceDirectory.appendingPathComponent("compile_commands.json")
+      to: testWorkspaceDirectory.appendingPathComponent(JSONCompilationDatabase.dbName)
     )
 
     // Run swiftc to build the index store