Support VirtualPaths in ToolChain

Sources/SwiftDriver/Driver/Driver.swift

@@ -251,7 +251,7 @@ public struct Driver {
         self.swiftCompilerPrefixArgs = []
       } else {
         let frontendPath = frontendCommandLine.removeFirst()
-        self.toolchain.overrideToolPath(.swiftCompiler, path: try AbsolutePath(validating: frontendPath))
+        self.toolchain.overrideToolPath(.swiftCompiler, path: try VirtualPath(path: frontendPath))
         self.swiftCompilerPrefixArgs = frontendCommandLine
       }
     } else {

Sources/SwiftDriver/Jobs/AutolinkExtractJob.swift

@@ -30,7 +30,7 @@ extension Driver {
 
     return Job(
       kind: .autolinkExtract,
-      tool: .absolute(try toolchain.getToolPath(.swiftAutolinkExtract)),
+      tool: try toolchain.getToolPath(.swiftAutolinkExtract),
       commandLine: commandLine,
       inputs: inputs,
       outputs: [.init(file: output, type: .autolink)],

Sources/SwiftDriver/Jobs/CompileJob.swift

@@ -196,7 +196,7 @@ extension Driver {
 
     return Job(
       kind: .compile,
-      tool: .absolute(try toolchain.getToolPath(.swiftCompiler)),
+      tool: try toolchain.getToolPath(.swiftCompiler),
       commandLine: commandLine,
       displayInputs: primaryInputs,
       inputs: inputs,

Sources/SwiftDriver/Jobs/DarwinToolchain+LinkerSupport.swift

@@ -13,7 +13,7 @@ import TSCBasic
 import SwiftOptions
 
 extension DarwinToolchain {
-  private func findARCLiteLibPath() throws -> AbsolutePath? {
+  private func findARCLiteLibPath() throws -> VirtualPath? {
     let path = try getToolPath(.swiftCompiler)
       .parentDirectory // 'swift'
       .parentDirectory // 'bin'
@@ -198,7 +198,7 @@ extension DarwinToolchain {
     sanitizers: Set<Sanitizer>,
     targetTriple: Triple,
     targetVariantTriple: Triple?
-  ) throws -> AbsolutePath {
+  ) throws -> VirtualPath {
 
     // FIXME: If we used Clang as a linker instead of going straight to ld,
     // we wouldn't have to replicate a bunch of Clang's logic here.
@@ -217,7 +217,7 @@ extension DarwinToolchain {
         parsedOptions: &parsedOptions)
       .appending(component: "libclang_rt.\(darwinPlatformSuffix).a")
     if localFileSystem.exists(compilerRTPath) {
-      commandLine.append(.path(.absolute(compilerRTPath)))
+      commandLine.append(.path(compilerRTPath))
     }
 
     // Set up for linking.

Sources/SwiftDriver/Jobs/EmitModuleJob.swift

@@ -70,7 +70,7 @@ extension Driver {
 
     return Job(
       kind: .emitModule,
-      tool: .absolute(try toolchain.getToolPath(.swiftCompiler)),
+      tool: try toolchain.getToolPath(.swiftCompiler),
       commandLine: commandLine,
       inputs: inputs,
       outputs: outputs

Sources/SwiftDriver/Jobs/GenerateDSYMJob.swift

@@ -24,7 +24,7 @@ extension Driver {
 
     return Job(
       kind: .generateDSYM,
-      tool: .absolute(try toolchain.getToolPath(.dsymutil)),
+      tool: try toolchain.getToolPath(.dsymutil),
       commandLine: commandLine,
       displayInputs: [],
       inputs: inputs,

Sources/SwiftDriver/Jobs/GeneratePCHJob.swift

@@ -63,7 +63,7 @@ extension Driver {
 
     return Job(
       kind: .generatePCH,
-      tool: .absolute(try toolchain.getToolPath(.swiftCompiler)),
+      tool: try toolchain.getToolPath(.swiftCompiler),
       commandLine: commandLine,
       displayInputs: [],
       inputs: inputs,

Sources/SwiftDriver/Jobs/GeneratePCMJob.swift

@@ -54,7 +54,7 @@ extension Driver {
 
     return Job(
       kind: .generatePCM,
-      tool: .absolute(try toolchain.getToolPath(.swiftCompiler)),
+      tool: try toolchain.getToolPath(.swiftCompiler),
       commandLine: commandLine,
       displayInputs: [],
       inputs: inputs,

Sources/SwiftDriver/Jobs/GenericUnixToolchain+LinkerSupport.swift

@@ -53,7 +53,7 @@ extension GenericUnixToolchain {
     sanitizers: Set<Sanitizer>,
     targetTriple: Triple,
     targetVariantTriple: Triple?
-  ) throws -> AbsolutePath {
+  ) throws -> VirtualPath {
     switch linkerOutputType {
     case .dynamicLibrary:
       // Same options as an executable, just with '-shared'
@@ -107,7 +107,7 @@ extension GenericUnixToolchain {
 
         // If there is a clang in the toolchain folder, use that instead.
         if let tool = lookupExecutablePath(filename: "clang", searchPaths: [toolsDir]) {
-          clangPath = tool
+          clangPath = .absolute(tool)
         }
 
         // Look for binutils in the toolchain folder.
@@ -191,7 +191,7 @@ extension GenericUnixToolchain {
       // Link the standard library. In two paths, we do this using a .lnk file
       // if we're going that route, we'll set `linkFilePath` to the path to that
       // file.
-      var linkFilePath: AbsolutePath? = try computeResourceDirPath(
+      var linkFilePath: VirtualPath? = try computeResourceDirPath(
         for: targetTriple,
         parsedOptions: &parsedOptions,
         isShared: false

Sources/SwiftDriver/Jobs/InterpretJob.swift

@@ -42,7 +42,7 @@ extension Driver {
 
     return Job(
       kind: .interpret,
-      tool: .absolute(try toolchain.getToolPath(.swiftCompiler)),
+      tool: try toolchain.getToolPath(.swiftCompiler),
       commandLine: commandLine,
       inputs:inputs,
       outputs: [],

Sources/SwiftDriver/Jobs/LinkJob.swift

@@ -55,7 +55,7 @@ extension Driver {
     // TODO: some, but not all, linkers support response files.
     return Job(
       kind: .link,
-      tool: .absolute(toolPath),
+      tool: toolPath,
       commandLine: commandLine,
       inputs: inputs,
       outputs: [.init(file: outputFile, type: .object)]

Sources/SwiftDriver/Jobs/MergeModuleJob.swift

@@ -51,7 +51,7 @@ extension Driver {
 
     return Job(
       kind: .mergeModule,
-      tool: .absolute(try toolchain.getToolPath(.swiftCompiler)),
+      tool: try toolchain.getToolPath(.swiftCompiler),
       commandLine: commandLine,
       inputs: inputs,
       outputs: outputs,

Sources/SwiftDriver/Jobs/Planning.swift

@@ -176,7 +176,7 @@ extension Driver {
       try commandLine.appendLast(.sdk, from: &parsedOptions)
       try commandLine.appendLast(.resourceDir, from: &parsedOptions)
       return Job(kind: .printTargetInfo,
-                 tool: .absolute(try toolchain.getToolPath(.swiftCompiler)),
+                 tool: try toolchain.getToolPath(.swiftCompiler),
                  commandLine: commandLine,
                  inputs: [],
                  outputs: [],
@@ -185,7 +185,7 @@ extension Driver {
 
     if parsedOptions.hasArgument(.version) || parsedOptions.hasArgument(.version_) {
       return Job(kind: .versionRequest,
-                 tool: .absolute(try toolchain.getToolPath(.swiftCompiler)),
+                 tool: try toolchain.getToolPath(.swiftCompiler),
                  commandLine: [.flag("--version")],
                  inputs: [],
                  outputs: [],
@@ -198,7 +198,7 @@ extension Driver {
         commandLine.append(.flag("-show-hidden"))
       }
       return Job(kind: .help,
-                 tool: .absolute(try toolchain.getToolPath(.swiftHelp)),
+                 tool: try toolchain.getToolPath(.swiftHelp),
                  commandLine: commandLine,
                  inputs: [],
                  outputs: [],

Sources/SwiftDriver/Jobs/ReplJob.swift

@@ -29,7 +29,7 @@ extension Driver {
       let lldbArg = "--repl=\(commandLine.joinedArguments)"
       return Job(
         kind: .repl,
-        tool: .absolute(try toolchain.getToolPath(.lldb)),
+        tool: try toolchain.getToolPath(.lldb),
         commandLine: [Job.ArgTemplate.flag(lldbArg)],
         inputs: [],
         outputs: [],
@@ -41,7 +41,7 @@ extension Driver {
       commandLine.appendFlags("-module-name", moduleName)
       return Job(
         kind: .repl,
-        tool: .absolute(try toolchain.getToolPath(.swiftCompiler)),
+        tool: try toolchain.getToolPath(.swiftCompiler),
         commandLine: commandLine,
         inputs: [],
         outputs: [],

Sources/SwiftDriver/Jobs/Toolchain+LinkerSupport.swift

@@ -19,13 +19,12 @@ extension Toolchain {
     for triple: Triple,
     parsedOptions: inout ParsedOptions,
     isShared: Bool
-  ) throws -> AbsolutePath {
-    // FIXME: This almost certainly won't be an absolute path in practice...
-    let resourceDirBase: AbsolutePath
+  ) throws -> VirtualPath {
+    let resourceDirBase: VirtualPath
     if let resourceDir = parsedOptions.getLastArgument(.resourceDir) {
-      resourceDirBase = try AbsolutePath(validating: resourceDir.asSingle)
+      resourceDirBase = try VirtualPath(path: resourceDir.asSingle)
     } else if let sdk = parsedOptions.getLastArgument(.sdk),
-      let sdkPath = try? AbsolutePath(validating: sdk.asSingle) {
+      let sdkPath = try? VirtualPath(path: sdk.asSingle) {
       resourceDirBase = sdkPath
         .appending(components: "usr", "lib",
                    isShared ? "swift" : "swift_static")
@@ -38,15 +37,15 @@ extension Toolchain {
     return resourceDirBase.appending(components: triple.platformName() ?? "")
   }
 
-  func computeSecondaryResourceDirPath(for triple: Triple, primaryPath: AbsolutePath) -> AbsolutePath? {
+  func computeSecondaryResourceDirPath(for triple: Triple, primaryPath: VirtualPath) -> VirtualPath? {
     guard triple.isMacCatalyst else { return nil }
     return primaryPath.parentDirectory.appending(component: "macosx")
   }
 
   func clangLibraryPath(
     for triple: Triple,
     parsedOptions: inout ParsedOptions
-  ) throws -> AbsolutePath {
+  ) throws -> VirtualPath {
     return try computeResourceDirPath(for: triple,
                                       parsedOptions: &parsedOptions,
                                       isShared: true)
@@ -60,7 +59,7 @@ extension Toolchain {
     parsedOptions: inout ParsedOptions,
     sdkPath: String?,
     isShared: Bool
-  ) throws -> [AbsolutePath] {
+  ) throws -> [VirtualPath] {
     let resourceDirPath = try computeResourceDirPath(
       for: triple,
       parsedOptions: &parsedOptions,
@@ -73,13 +72,13 @@ extension Toolchain {
     }
 
     if let path = sdkPath {
-      let sdkPath = AbsolutePath(path)
+      let sdkPath = try VirtualPath(path: path)
       // If we added the secondary resource dir, we also need the iOSSupport directory.
       if secondaryResourceDir != nil {
         result.append(sdkPath.appending(components: "System", "iOSSupport", "usr", "lib", "swift"))
       }
 
-      result.append(sdkPath.appending(RelativePath("usr/lib/swift")))
+      result.append(sdkPath.appending(components: "usr", "lib", "swift"))
     }
 
     return result
@@ -263,12 +262,12 @@ extension DarwinToolchain {
       }
     }
 
-    func paths(runtimeLibraryPaths: [AbsolutePath]) -> [AbsolutePath] {
+    func paths(runtimeLibraryPaths: [VirtualPath]) -> [VirtualPath] {
       switch self {
       case .toolchain:
         return runtimeLibraryPaths
       case .os:
-        return [AbsolutePath("/usr/lib/swift")]
+        return [.absolute(AbsolutePath("/usr/lib/swift"))]
       case .none:
         return []
       }

Sources/SwiftDriver/Jobs/VerifyDebugInfoJob.swift

@@ -22,7 +22,7 @@ extension Driver {
 
     return Job(
       kind: .verifyDebugInfo,
-      tool: .absolute(try toolchain.getToolPath(.dwarfdump)),
+      tool: try toolchain.getToolPath(.dwarfdump),
       commandLine: commandLine,
       displayInputs: [],
       inputs: inputs,

Sources/SwiftDriver/Toolchains/DarwinToolchain.swift

@@ -18,14 +18,14 @@ public final class DarwinToolchain: Toolchain {
   public let env: [String: String]
 
   /// Doubles as path cache and point for overriding normal lookup
-  private var toolPaths = [Tool: AbsolutePath]()
+  private var toolPaths = [Tool: VirtualPath]()
 
   public init(env: [String: String]) {
     self.env = env
   }
 
   /// Retrieve the absolute path for a given tool.
-  public func getToolPath(_ tool: Tool) throws -> AbsolutePath {
+  public func getToolPath(_ tool: Tool) throws -> VirtualPath {
     // Check the cache
     if let toolPath = toolPaths[tool] {
       return toolPath
@@ -36,7 +36,7 @@ public final class DarwinToolchain: Toolchain {
     return path
   }
 
-  private func lookupToolPath(_ tool: Tool) throws -> AbsolutePath {
+  private func lookupToolPath(_ tool: Tool) throws -> VirtualPath {
     switch tool {
     case .swiftCompiler:
       return try lookup(executable: "swift")
@@ -55,7 +55,7 @@ public final class DarwinToolchain: Toolchain {
         arguments: ["xcrun", "-toolchain", "default", "-f", "clang"],
         environment: env
       ).spm_chomp()
-      return AbsolutePath(result)
+      return .absolute(AbsolutePath(result))
     case .swiftAutolinkExtract:
       return try lookup(executable: "swift-autolink-extract")
     case .lldb:
@@ -67,7 +67,7 @@ public final class DarwinToolchain: Toolchain {
     }
   }
 
-  public func overrideToolPath(_ tool: Tool, path: AbsolutePath) {
+  public func overrideToolPath(_ tool: Tool, path: VirtualPath) {
     toolPaths[tool] = path
   }
 
@@ -85,10 +85,10 @@ public final class DarwinToolchain: Toolchain {
     sdk.appending(RelativePath("usr/lib/swift"))
   }
 
-  public var resourcesDirectory: Result<AbsolutePath, Swift.Error> {
+  public var resourcesDirectory: Result<VirtualPath, Swift.Error> {
     // FIXME: This will need to take -resource-dir and target triple into account.
     return Result {
-      try getToolPath(.swiftCompiler).appending(RelativePath("../../lib/swift/macosx"))
+      try getToolPath(.swiftCompiler).appending(components: "..", "..", "lib", "swift", "macosx")
     }
   }
 
@@ -100,16 +100,16 @@ public final class DarwinToolchain: Toolchain {
     }
   }
 
-  public var compatibility50: Result<AbsolutePath, Error> {
+  public var compatibility50: Result<VirtualPath, Error> {
     resourcesDirectory.map{ $0.appending(component: "libswiftCompatibility50.a") }
   }
 
-  public var compatibilityDynamicReplacements: Result<AbsolutePath, Error> {
+  public var compatibilityDynamicReplacements: Result<VirtualPath, Error> {
     resourcesDirectory.map{ $0.appending(component: "libswiftCompatibilityDynamicReplacements.a") }
   }
 
-  public var clangRT: Result<AbsolutePath, Error> {
-    resourcesDirectory.map{ $0.appending(RelativePath("../clang/lib/darwin/libclang_rt.osx.a")) }
+  public var clangRT: Result<VirtualPath, Error> {
+    resourcesDirectory.map{ $0.appending(components: "..", "clang", "lib", "darwin", "libclang_rt.osx.a") }
   }
 
   public func defaultSDKPath() throws -> AbsolutePath? {

Sources/SwiftDriver/Toolchains/GenericUnixToolchain.swift

@@ -16,7 +16,7 @@ public final class GenericUnixToolchain: Toolchain {
   public let env: [String: String]
 
   /// Doubles as path cache and point for overriding normal lookup
-  private var toolPaths = [Tool: AbsolutePath]()
+  private var toolPaths = [Tool: VirtualPath]()
 
   public init(env: [String: String]) {
     self.env = env
@@ -31,7 +31,7 @@ public final class GenericUnixToolchain: Toolchain {
   }
 
   /// Retrieve the absolute path for a given tool.
-  public func getToolPath(_ tool: Tool) throws -> AbsolutePath {
+  public func getToolPath(_ tool: Tool) throws -> VirtualPath {
     // Check the cache
     if let toolPath = toolPaths[tool] {
       return toolPath
@@ -42,7 +42,7 @@ public final class GenericUnixToolchain: Toolchain {
     return path
   }
 
-  private func lookupToolPath(_ tool: Tool) throws -> AbsolutePath {
+  private func lookupToolPath(_ tool: Tool) throws -> VirtualPath {
     switch tool {
     case .swiftCompiler:
       return try lookup(executable: "swift")
@@ -66,7 +66,7 @@ public final class GenericUnixToolchain: Toolchain {
     }
   }
 
-  public func overrideToolPath(_ tool: Tool, path: AbsolutePath) {
+  public func overrideToolPath(_ tool: Tool, path: VirtualPath) {
     toolPaths[tool] = path
   }