Simplify some code by introducing an enum for SDK platform kind. NFC

Author: nkcsgexi

Sources/SwiftDriver/Jobs/PrebuiltModulesJob.swift

@@ -233,35 +233,22 @@ public struct SDKPrebuiltModuleInputsCollector {
 
   // Returns a target triple that's proper to use with the given SDK path.
   public var targetTriple: String {
-    let canonicalName = sdkInfo.canonicalName
-    func extractVersion(_ platform: String) -> Substring? {
-      if canonicalName.starts(with: platform) {
-        let versionStartIndex = canonicalName.index(canonicalName.startIndex,
-                                                    offsetBy: platform.count)
-        let delimiterRange = canonicalName.range(of: "internal", options: .backwards)
-        let versionEndIndex = delimiterRange == nil ? canonicalName.endIndex : delimiterRange!.lowerBound
-        return canonicalName[versionStartIndex..<versionEndIndex]
-      }
-      return nil
-    }
-
-    if let version = extractVersion("macosx") {
+    let version = sdkInfo.versionString
+    switch sdkInfo.platformKind {
+    case .macosx:
       return "arm64-apple-macosx\(version)"
-    } else if let version = extractVersion("iphoneos") {
+    case .iphoneos:
       return "arm64-apple-ios\(version)"
-    } else if let version = extractVersion("iphonesimulator") {
+    case .iphonesimulator:
       return "arm64-apple-ios\(version)-simulator"
-    } else if let version = extractVersion("watchos") {
+    case .watchos:
       return "armv7k-apple-watchos\(version)"
-    } else if let version = extractVersion("watchsimulator") {
+    case .watchsimulator:
       return "arm64-apple-watchos\(version)-simulator"
-    } else if let version = extractVersion("appletvos") {
+    case .appletvos:
       return "arm64-apple-tvos\(version)"
-    } else if let version = extractVersion("appletvsimulator") {
+    case .appletvsimulator:
       return "arm64-apple-tvos\(version)-simulator"
-    } else {
-      diagEngine.emit(error: "unhandled platform name: \(canonicalName)")
-      return ""
     }
   }
 

Sources/SwiftDriver/Toolchains/DarwinToolchain.swift

@@ -240,6 +240,16 @@ public final class DarwinToolchain: Toolchain {
       case canonicalName = "CanonicalName"
     }
 
+    public enum SDKPlatformKind: String {
+      case macosx
+      case iphoneos
+      case iphonesimulator
+      case watchos
+      case watchsimulator
+      case appletvos
+      case appletvsimulator
+    }
+
     struct VersionMap: Decodable {
       private enum CodingKeys: String, CodingKey {
         case macOSToCatalystMapping = "macOS_iOSMac"
@@ -269,6 +279,7 @@ public final class DarwinToolchain: Toolchain {
       }
     }
     public let versionString: String
+    public let platformKind: SDKPlatformKind
     private var version: Version
     private var versionMap: VersionMap
     let canonicalName: String
@@ -277,6 +288,8 @@ public final class DarwinToolchain: Toolchain {
 
       self.versionString = try keyedContainer.decode(String.self, forKey: .version)
       self.canonicalName = try keyedContainer.decode(String.self, forKey: .canonicalName)
+      assert(canonicalName.hasSuffix(versionString))
+      self.platformKind = SDKPlatformKind(rawValue: String(canonicalName.prefix(canonicalName.count - versionString.count)))!
       guard let version = try? Version(versionString: versionString, usesLenientParsing: true) else {
         throw DecodingError.dataCorruptedError(forKey: .version,
                                                in: keyedContainer,
@@ -290,6 +303,7 @@ public final class DarwinToolchain: Toolchain {
       }
     }
 
+
     func sdkVersion(for triple: Triple) -> Version {
       if triple.isMacCatalyst {
         // For the Mac Catalyst environment, we have a macOS SDK with a macOS