Adopt swift-subprocess when running unit tests

CMakeLists.txt

@@ -47,6 +47,7 @@ if(FIND_PM_DEPS)
   find_package(SwiftCertificates CONFIG REQUIRED)
   find_package(SwiftCrypto CONFIG REQUIRED)
   find_package(SwiftBuild CONFIG REQUIRED)
+  find_package(SwiftSubprocess CONFIG REQUIRED)
 endif()
 
 find_package(dispatch QUIET)

Package.swift

@@ -239,6 +239,7 @@ let package = Package(
             dependencies: [
                 "_AsyncFileSystem",
                 .target(name: "SPMSQLite3", condition: .when(platforms: [.macOS, .iOS, .tvOS, .watchOS, .visionOS, .macCatalyst, .linux, .openbsd, .custom("freebsd")])),
+                .product(name: "Subprocess", package: "swift-subprocess"),
                 .product(name: "SwiftToolchainCSQLite", package: "swift-toolchain-sqlite", condition: .when(platforms: [.windows, .android])),
                 .product(name: "DequeModule", package: "swift-collections"),
                 .product(name: "OrderedCollections", package: "swift-collections"),
@@ -575,6 +576,7 @@ let package = Package(
             dependencies: [
                 .product(name: "ArgumentParser", package: "swift-argument-parser"),
                 .product(name: "OrderedCollections", package: "swift-collections"),
+                .product(name: "Subprocess", package: "swift-subprocess"),
                 "Basics",
                 "BinarySymbols",
                 "Build",
@@ -1113,6 +1115,7 @@ if ProcessInfo.processInfo.environment["SWIFTCI_USE_LOCAL_DEPS"] == nil {
         .package(url: "https://github.com/apple/swift-system.git", revision: "1.5.0"),
         .package(url: "https://github.com/apple/swift-collections.git", revision: "1.1.6"),
         .package(url: "https://github.com/apple/swift-certificates.git", revision: "1.10.1"),
+        .package(url: "https://github.com/swiftlang/swift-subprocess.git", .upToNextMinor(from: "0.2.0")),
         .package(url: "https://github.com/swiftlang/swift-toolchain-sqlite.git", revision: "1.0.7"),
         // Not in toolchain, used for use in previewing documentation
         .package(url: "https://github.com/swiftlang/swift-docc-plugin", from: "1.1.0"),
@@ -1131,6 +1134,7 @@ if ProcessInfo.processInfo.environment["SWIFTCI_USE_LOCAL_DEPS"] == nil {
         .package(path: "../swift-system"),
         .package(path: "../swift-collections"),
         .package(path: "../swift-certificates"),
+        .package(path: "../swift-subprocess"),
         .package(path: "../swift-toolchain-sqlite"),
     ]
     if !swiftDriverDeps.isEmpty {

Sources/Basics/CMakeLists.txt

@@ -73,6 +73,7 @@ add_library(Basics
   Serialization/SerializedJSON.swift
   SwiftVersion.swift
   SQLiteBackedCache.swift
+  Subprocess+Extensions.swift
   TestingLibrary.swift
   Triple+Basics.swift
   URL.swift
@@ -83,6 +84,7 @@ add_library(Basics
 target_link_libraries(Basics PUBLIC
   _AsyncFileSystem
   SwiftCollections::OrderedCollections
+  SwiftSubprocess::Subprocess
   TSCBasic
   TSCUtility)
 target_link_libraries(Basics PRIVATE

Sources/Basics/Cancellator.swift

@@ -190,6 +190,17 @@ public final class Cancellator: Cancellable, Sendable {
     }
 }
 
+extension Cancellator {
+    public func run<T: Sendable>(name: String, _ block: @escaping @Sendable () async throws -> T) async throws -> T {
+        let task = Task { try await block() }
+        let token = register(name: name, handler: { _ in task.cancel() })
+        defer {
+            token.map { deregister($0) }
+        }
+        return try await task.value
+    }
+}
+
 public protocol Cancellable {
     func cancel(deadline: DispatchTime) throws -> Void
 }

Sources/Basics/Subprocess+Extensions.swift

@@ -0,0 +1,39 @@
+//===----------------------------------------------------------------------===//
+//
+// This source file is part of the Swift open source project
+//
+// Copyright (c) 2021 Apple Inc. and the Swift project authors
+// Licensed under Apache License v2.0 with Runtime Library Exception
+//
+// See http://swift.org/LICENSE.txt for license information
+// See http://swift.org/CONTRIBUTORS.txt for the list of Swift project authors
+//
+//===----------------------------------------------------------------------===//
+
+import Subprocess
+import TSCBasic
+
+#if canImport(System)
+import System
+#else
+import SystemPackage
+#endif
+
+extension Subprocess.Environment {
+    public init(_ env: Basics.Environment) {
+        var newEnv: [Subprocess.Environment.Key: String] = [:]
+        for (key, value) in env {
+            newEnv[.init(rawValue: key.rawValue)!] = value
+        }
+        self = Subprocess.Environment.custom(newEnv)
+    }
+}
+
+extension Subprocess.Configuration {
+    public init(commandLine: [String], environment: Subprocess.Environment) throws {
+        guard let arg0 = commandLine.first else {
+            throw StringError("command line was unexpectedly empty")
+        }
+        self.init(.path(FilePath(arg0)), arguments: .init(Array(commandLine.dropFirst())), environment: environment)
+    }
+}

Sources/Commands/CMakeLists.txt

@@ -61,6 +61,7 @@ add_library(Commands
 target_link_libraries(Commands PUBLIC
   SwiftCollections::OrderedCollections
   SwiftSyntax::SwiftRefactor
+  SwiftSubprocess::Subprocess
   ArgumentParser
   Basics
   BinarySymbols