Support building for architectures other than x86_64 on macOS (Apple …

…Silicon) (#185)

* Add and test new 'ProfileInfo.machineHardwareName' property

* Update 'Mint.install(package:executable:beforeOtherCommand:force:link:noInstall:)' method to construct 'swift build' command that specifies the correct target architecture in order to support building on Apple Silicon

* Remove use of XCTSkipIf to preserve support for Xcode 10.2

* Update CHANGELOG.md

* Clean up ProcessInfoExtensionTests by removing print for skipped tests

CHANGELOG.md

@@ -5,6 +5,9 @@
 #### Added
 - Running offline without specified version [#164](https://github.com/yonaskolb/Mint/issues/164) [#166](https://github.com/yonaskolb/Mint/pull/166) @vknabel
 
+#### Fixed
+- Support building for architectures other than x86_64 on macOS (Apple Silicon) [#185](https://github.com/yonaskolb/Mint/pull/185)
+
 ## 0.14.2
 
 #### Changed

Sources/MintKit/Mint.swift

@@ -329,9 +329,12 @@ public class Mint {
 
         var buildCommand = "swift build -c release"
         #if os(macOS)
-            let osVersion = ProcessInfo.processInfo.operatingSystemVersion
-            let target = "x86_64-apple-macosx\(osVersion.majorVersion).\(osVersion.minorVersion)"
-            buildCommand += " -Xswiftc -target -Xswiftc \(target)"
+            let processInfo = ProcessInfo.processInfo
+            if let machineHardwareName = processInfo.machineHardwareName {
+                let osVersion = ProcessInfo.processInfo.operatingSystemVersion
+                let target = "\(machineHardwareName)-apple-macosx\(osVersion.majorVersion).\(osVersion.minorVersion)"
+                buildCommand += " -Xswiftc -target -Xswiftc \(target)"
+            }
         #endif
 
         try runPackageCommand(name: "Building package",

Sources/MintKit/ProcessInfoExtensions.swift

@@ -0,0 +1,17 @@
+import Foundation
+
+extension ProcessInfo {
+    /// Returns a `String` representing the machine hardware name or nil if there was an error invoking `uname(_:)` or decoding the response.
+    ///
+    /// Return value is the equivalent to running `$ uname -m` in shell.
+    var machineHardwareName: String? {
+        var sysinfo = utsname()
+        let result = uname(&sysinfo)
+        guard result == EXIT_SUCCESS else { return nil }
+
+        let data = Data(bytes: &sysinfo.machine, count: Int(_SYS_NAMELEN))
+
+        guard let identifier = String(bytes: data, encoding: .ascii) else { return nil }
+        return identifier.trimmingCharacters(in: .controlCharacters)
+    }
+}

Tests/MintTests/ProcessInfoExtensionTests.swift

@@ -0,0 +1,16 @@
+@testable import MintKit
+import XCTest
+
+final class ProcessInfoExtensionTests: XCTestCase {
+    #if arch(x86_64)
+    func testMachineHardwareName_Intel() {
+        XCTAssertEqual(ProcessInfo.processInfo.machineHardwareName, "x86_64")
+    }
+    #endif
+
+    #if arch(arm64)
+    func testMachineHardwareName_AppleSilicone() {
+        XCTAssertEqual(ProcessInfo.processInfo.machineHardwareName, "arm64")
+    }
+    #endif
+}