Make the package build on all Apple platforms

Although the functionality is not available on iOS-derived platforms, this can make cross platform development smoother.

Author: jakepetroules

Package.swift

@@ -4,7 +4,7 @@
 import PackageDescription
 
 let availabilityMacro: SwiftSetting = .enableExperimentalFeature(
-    "AvailabilityMacro=SubprocessSpan: macOS 9999",
+    "AvailabilityMacro=SubprocessSpan: macOS 9999, iOS 9999, tvOS 9999, watchOS 9999, visionOS 9999",
 )
 
 var dep: [Package.Dependency] = [
@@ -31,7 +31,7 @@ defaultTraits.insert("SubprocessSpan")
 
 let package = Package(
     name: "Subprocess",
-    platforms: [.macOS(.v13)],
+    platforms: [.macOS(.v13), .iOS(.v16)],
     products: [
         .library(
             name: "Subprocess",

[email protected]

@@ -4,12 +4,12 @@
 import PackageDescription
 
 let availabilityMacro: SwiftSetting = .enableExperimentalFeature(
-    "AvailabilityMacro=SubprocessSpan: macOS 9999"
+    "AvailabilityMacro=SubprocessSpan: macOS 9999, iOS 9999, tvOS 9999, watchOS 9999, visionOS 9999",
 )
 
 let package = Package(
     name: "Subprocess",
-    platforms: [.macOS(.v13)],
+    platforms: [.macOS(.v13), .iOS(.v16)]],
     products: [
         .library(
             name: "Subprocess",

Sources/Subprocess/Atomic.swift

@@ -37,7 +37,7 @@ internal struct AtomicBox: Sendable, ~Copyable {
 
     internal init() {
         #if canImport(Synchronization)
-        guard #available(macOS 15, *) else {
+        guard #available(macOS 15, iOS 18, tvOS 18, watchOS 11, visionOS 2, *) else {
             fatalError("Unexpected configuration")
         }
         let box = Atomic(UInt8(0))
@@ -62,7 +62,7 @@ internal struct AtomicBox: Sendable, ~Copyable {
 }
 
 #if canImport(Synchronization)
-@available(macOS 15, *)
+@available(macOS 15, iOS 18, tvOS 18, watchOS 11, visionOS 2, *)
 extension Atomic where Value == UInt8 {
     borrowing func _bitwiseXor(
         _ operand: OutputConsumptionState

Sources/Subprocess/Platforms/Subprocess+Darwin.swift

@@ -166,6 +166,9 @@ extension Configuration {
         error: Error,
         errorPipe: CreatedPipe
     ) throws -> Execution<Output, Error> {
+        #if !os(macOS)
+        throw SubprocessError(code: .init(.spawnFailed), underlyingError: .init(rawValue: ENOTSUP))
+        #else
         // Instead of checking if every possible executable path
         // is valid, spawn each directly and catch ENOENT
         let possiblePaths = self.executable.possibleExecutablePaths(
@@ -377,6 +380,7 @@ extension Configuration {
                 underlyingError: .init(rawValue: ENOENT)
             )
         }
+        #endif
     }
 }
 

Sources/_SubprocessCShims/process_shims.c

@@ -84,7 +84,7 @@ vm_size_t _subprocess_vm_size(void) {
 #endif
 
 // MARK: - Darwin (posix_spawn)
-#if TARGET_OS_MAC
+#if TARGET_OS_OSX
 static int _subprocess_spawn_prefork(
     pid_t  * _Nonnull  pid,
     const char  * _Nonnull  exec_path,
@@ -247,7 +247,7 @@ int _subprocess_spawn(
     return posix_spawn(pid, exec_path, file_actions, spawn_attrs, args, env);
 }
 
-#endif // TARGET_OS_MAC
+#endif // TARGET_OS_OSX
 
 // MARK: - Linux (fork/exec + posix_spawn fallback)
 #if TARGET_OS_LINUX

Tests/SubprocessTests/SubprocessTests+Darwin.swift

@@ -32,11 +32,13 @@ struct SubprocessDarwinTests {
         }
         var platformOptions = PlatformOptions()
         platformOptions.preSpawnProcessConfigurator = { spawnAttr, _ in
+            #if os(macOS)
             // Set POSIX_SPAWN_SETSID flag, which implies calls
             // to setsid
             var flags: Int16 = 0
             posix_spawnattr_getflags(&spawnAttr, &flags)
             posix_spawnattr_setflags(&spawnAttr, flags | Int16(POSIX_SPAWN_SETSID))
+            #endif
         }
         // Check the proces ID (pid), pross group ID (pgid), and
         // controling terminal's process group ID (tpgid)
@@ -56,10 +58,12 @@ struct SubprocessDarwinTests {
         let intendedWorkingDir = FileManager.default.temporaryDirectory.path()
         var platformOptions = PlatformOptions()
         platformOptions.preSpawnProcessConfigurator = { _, fileAttr in
+            #if os(macOS)
             // Change the working directory
             intendedWorkingDir.withCString { path in
                 _ = posix_spawn_file_actions_addchdir_np(&fileAttr, path)
             }
+            #endif
         }
         let pwdResult = try await Subprocess.run(
             .path("/bin/pwd"),

Tests/SubprocessTests/SubprocessTests+Linting.swift

@@ -25,7 +25,7 @@ private func enableLintingTest() -> Bool {
     } catch {
         return false
     }
-    #elseif os(Linux) || os(Windows)
+    #else
     // Use swift-format directly
     do {
         _ = try Executable.name("swift-format")
@@ -66,7 +66,7 @@ struct SubprocessLintingTest {
             executable: .path("/usr/bin/xcrun"),
             arguments: ["swift-format", "lint", "-s", "--recursive", sourcePath]
         )
-        #elseif os(Linux) || os(Windows)
+        #else
         let configuration = Configuration(
             executable: .name("swift-format"),
             arguments: ["lint", "-s", "--recursive", sourcePath]