Derive executable file name from Toolchain

Author: stevapple

Sources/SwiftDriver/Toolchains/DarwinToolchain.swift

@@ -20,15 +20,18 @@ import SwiftOptions
 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]()
-
   /// The executor used to run processes used to find tools and retrieve target info.
   public let executor: DriverExecutor
 
   /// The file system to use for any file operations.
   public let fileSystem: FileSystem
 
+  /// The suffix of executable files.
+  public let executableSuffix = ""
+
+  /// Doubles as path cache and point for overriding normal lookup
+  private var toolPaths = [Tool: AbsolutePath]()
+
   public init(env: [String: String], executor: DriverExecutor, fileSystem: FileSystem = localFileSystem) {
     self.env = env
     self.executor = executor

Sources/SwiftDriver/Toolchains/GenericUnixToolchain.swift

@@ -21,6 +21,9 @@ public final class GenericUnixToolchain: Toolchain {
   /// The file system to use for queries.
   public let fileSystem: FileSystem
 
+  /// The suffix of executable files.
+  public let executableSuffix = ""
+
   /// Doubles as path cache and point for overriding normal lookup
   private var toolPaths = [Tool: AbsolutePath]()
 

Sources/SwiftDriver/Toolchains/Toolchain.swift

@@ -38,6 +38,8 @@ public protocol Toolchain {
 
   var executor: DriverExecutor { get }
 
+  var executableSuffix: String { get }
+
   /// Retrieve the absolute path to a particular tool.
   func getToolPath(_ tool: Tool) throws -> AbsolutePath
 
@@ -129,26 +131,25 @@ extension Toolchain {
   /// looks in the `executableDir`, `xcrunFind` or in the `searchPaths`.
   /// - Parameter executable: executable to look for [i.e. `swift`].
   func lookup(executable: String) throws -> AbsolutePath {
+    let filename = executable + executableSuffix
     if let overrideString = envVar(forExecutable: executable) {
       return try AbsolutePath(validating: overrideString)
-    } else if let path = lookupExecutablePath(filename: executable, searchPaths: [executableDir]) {
+    } else if let path = lookupExecutablePath(filename: filename, searchPaths: [executableDir]) {
       return path
     } else if let path = try? xcrunFind(executable: executable) {
       return path
-    } else if !["swift-frontend", "swift", "swift-frontend.exe", "swift.exe"].contains(executable),
-              let parentDirectory = try? getToolPath(.swiftCompiler).parentDirectory,
-              parentDirectory != executableDir,
-              let path = lookupExecutablePath(filename: executable, searchPaths: [parentDirectory]) {
+    } else if !["swift-frontend", "swift"].contains(executable),
+        let parentDirectory = try? getToolPath(.swiftCompiler).parentDirectory,
+        parentDirectory != executableDir,
+        let path = lookupExecutablePath(filename: filename, searchPaths: [parentDirectory]) {
       // If the driver library's client and the frontend are in different directories,
       // try looking for tools next to the frontend.
       return path
-    } else if let path = lookupExecutablePath(filename: executable, searchPaths: searchPaths) {
+    } else if let path = lookupExecutablePath(filename: filename, searchPaths: searchPaths) {
       return path
-    // Temporary shim: fall back to looking for "swift" before failing.
     } else if executable == "swift-frontend" {
+      // Temporary shim: fall back to looking for "swift" before failing.
       return try lookup(executable: "swift")
-    } else if executable == "swift-frontend.exe" {
-      return try lookup(executable: "swift.exe")
     } else if fallbackToExecutableDefaultPath {
       return AbsolutePath("/usr/bin/" + executable)
     } else {

Sources/SwiftDriver/Toolchains/WindowsToolchain.swift

@@ -21,6 +21,9 @@ public final class WindowsToolchain: Toolchain {
   /// The file system to use for queries.
   public let fileSystem: FileSystem
 
+  /// The suffix of executable files.
+  public let executableSuffix = ".exe"
+
   /// Doubles as path cache and point for overriding normal lookup
   private var toolPaths = [Tool: AbsolutePath]()
 
@@ -53,24 +56,24 @@ public final class WindowsToolchain: Toolchain {
   private func lookupToolPath(_ tool: Tool) throws -> AbsolutePath {
     switch tool {
     case .swiftCompiler:
-      return try lookup(executable: "swift-frontend.exe")
+      return try lookup(executable: "swift-frontend")
     case .staticLinker:
-      return try lookup(executable: "lib.exe")
+      return try lookup(executable: "lib")
     case .dynamicLinker:
       // FIXME: This needs to look in the tools_directory first.
-      return try lookup(executable: "link.exe")
+      return try lookup(executable: "link")
     case .clang:
-      return try lookup(executable: "clang.exe")
+      return try lookup(executable: "clang")
     case .swiftAutolinkExtract:
       fatalError("Trying to look up \"swift-autolink-extract\" on Windows")
     case .dsymutil:
       fatalError("Trying to look up \"dsymutil\" on Windows")
     case .lldb:
-      return try lookup(executable: "lldb.exe")
+      return try lookup(executable: "lldb")
     case .dwarfdump:
-      return try lookup(executable: "llvm-dwarfdump.exe")
+      return try lookup(executable: "llvm-dwarfdump")
     case .swiftHelp:
-      return try lookup(executable: "swift-help.exe")
+      return try lookup(executable: "swift-help")
     }
   }