Add -scanner-prefix-map-paths option and fix multiArg option parsing

Sources/SwiftDriver/Driver/Driver.swift

@@ -296,7 +296,7 @@ public struct Driver {
       return ($0.key, $0.value)
     }
     do {
-      guard isFrontendArgSupported(.scannerPrefixMap) else {
+      guard isFrontendArgSupported(.scannerPrefixMapPaths) else {
         return []
       }
       if let sdkMapping = scannerPrefixMapSDK,
@@ -4007,14 +4007,20 @@ extension Driver {
 
   static func computeScanningPrefixMapper(_ parsedOptions: inout ParsedOptions) throws -> [AbsolutePath: AbsolutePath] {
     var mapping: [AbsolutePath: AbsolutePath] = [:]
-    for opt in parsedOptions.arguments(for: .scannerPrefixMap) {
-      let pluginArg = opt.argument.asSingle.split(separator: "=", maxSplits: 1)
-      if pluginArg.count != 2 {
-        throw Error.invalidArgumentValue(Option.scannerPrefixMap.spelling, opt.argument.asSingle)
+    for opt in parsedOptions.arguments(for: .scannerPrefixMapPaths, .scannerPrefixMap) {
+      if opt.option == .scannerPrefixMapPaths {
+        let key = try AbsolutePath(validating: opt.argument.asMultiple[0])
+        let value = try AbsolutePath(validating: opt.argument.asMultiple[1])
+        mapping[key] = value
+      } else {
+        let pluginArg = opt.argument.asSingle.split(separator: "=", maxSplits: 1)
+        if pluginArg.count != 2 {
+          throw Error.invalidArgumentValue(Option.scannerPrefixMap.spelling, opt.argument.asSingle)
+        }
+        let key = try AbsolutePath(validating: String(pluginArg[0]))
+        let value = try AbsolutePath(validating: String(pluginArg[1]))
+        mapping[key] = value
       }
-      let key = try AbsolutePath(validating: String(pluginArg[0]))
-      let value = try AbsolutePath(validating: String(pluginArg[1]))
-      mapping[key] = value
     }
     return mapping
   }

Sources/SwiftDriver/ExplicitModuleBuilds/ExplicitDependencyBuildPlanner.swift

@@ -216,7 +216,8 @@ public typealias ExternalTargetModuleDetailsMap = [ModuleDependencyId: ExternalT
       // Add prefix mapping. The option is cache invariant so it can be added without affecting cache key.
       for (key, value) in prefixMap {
         commandLine.appendFlag("-cache-replay-prefix-map")
-        commandLine.appendFlag(value.pathString + "=" + key.pathString)
+        commandLine.appendFlag(value.pathString)
+        commandLine.appendFlag(key.pathString)
       }
 
       jobs.append(Job(
@@ -277,7 +278,8 @@ public typealias ExternalTargetModuleDetailsMap = [ModuleDependencyId: ExternalT
       // Add prefix mapping. The option is cache invariant so it can be added without affecting cache key.
       for (key, value) in prefixMap {
         commandLine.appendFlag("-cache-replay-prefix-map")
-        commandLine.appendFlag(value.pathString + "=" + key.pathString)
+        commandLine.appendFlag(value.pathString)
+        commandLine.appendFlag(key.pathString)
       }
 
       jobs.append(Job(

Sources/SwiftDriver/ExplicitModuleBuilds/ModuleDependencyScanning.swift

@@ -125,11 +125,12 @@ public extension Driver {
       commandLine.appendFlag(.scannerModuleValidation)
     }
 
-    if isFrontendArgSupported(.scannerPrefixMap) {
-      // construct `-scanner-prefix-mapper` for scanner.
+    if isFrontendArgSupported(.scannerPrefixMapPaths) {
+      // construct `-scanner-prefix-map-paths` for scanner.
       for (key, value) in prefixMapping {
-        commandLine.appendFlag(.scannerPrefixMap)
-        commandLine.appendFlag(key.pathString + "=" + value.pathString)
+        commandLine.appendFlag(.scannerPrefixMapPaths)
+        commandLine.appendFlag(key.pathString)
+        commandLine.appendFlag(value.pathString)
       }
     }
 

Sources/SwiftDriver/Jobs/FrontendJobHelpers.swift

@@ -1031,10 +1031,11 @@ extension Driver {
   }
 
   public mutating func addCacheReplayMapping(to commandLine: inout [Job.ArgTemplate]) {
-    if isCachingEnabled && isFrontendArgSupported(.scannerPrefixMap) {
+    if isCachingEnabled && isFrontendArgSupported(.scannerPrefixMapPaths) {
       for (key, value) in prefixMapping {
         commandLine.appendFlag("-cache-replay-prefix-map")
-        commandLine.appendFlag(value.pathString + "=" + key.pathString)
+        commandLine.appendFlag(value.pathString)
+        commandLine.appendFlag(key.pathString)
       }
     }
   }

Sources/SwiftOptions/OptionParsing.swift

@@ -182,10 +182,8 @@ extension OptionTable {
           throw OptionParseError.missingArgument(
             index: index - 1, argument: argument)
         }
-        parsedOptions.addOption(option, argument: .multiple(Array()))
-        arguments[index..<endIdx].map { String($0) }.forEach { parsedOptions.addInput($0) }
+        parsedOptions.addOption(option, argument: .multiple(arguments[index..<endIdx].map { String($0) }))
         index = endIdx
-
       }
     }
     parsedOptions.buildIndex()

Sources/SwiftOptions/Options.swift

@@ -70,7 +70,7 @@ extension Option {
   public static let bypassResilience: Option = Option("-bypass-resilience-checks", .flag, attributes: [.helpHidden, .frontend, .noDriver], helpText: "Ignore all checks for module resilience.")
   public static let cacheCompileJob: Option = Option("-cache-compile-job", .flag, attributes: [.frontend], helpText: "Enable compiler caching")
   public static let cacheDisableReplay: Option = Option("-cache-disable-replay", .flag, attributes: [.frontend, .cacheInvariant], helpText: "Skip loading the compilation result from cache")
-  public static let cacheReplayPrefixMap: Option = Option("-cache-replay-prefix-map", .separate, attributes: [.frontend, .noDriver, .cacheInvariant], metaVar: "<prefix=replacement>", helpText: "Remap paths when replaying outputs from cache")
+  public static let cacheReplayPrefixMap: Option = Option("-cache-replay-prefix-map", .multiArg, attributes: [.frontend, .noDriver, .cacheInvariant], metaVar: "<prefix> <replacement>", helpText: "Remap paths when replaying outputs from cache", numArgs: 2)
   public static let candidateModuleFile: Option = Option("-candidate-module-file", .separate, attributes: [.helpHidden, .frontend, .noDriver], metaVar: "<path>", helpText: "Specify Swift module may be ready to use for an interface")
   public static let casBackendMode: Option = Option("-cas-backend-mode=", .joined, attributes: [.frontend, .noDriver], metaVar: "native|casid|verify", helpText: "CASBackendMode for output kind")
   public static let casBackend: Option = Option("-cas-backend", .flag, attributes: [.frontend, .noDriver], helpText: "Enable using CASBackend for object file output")
@@ -833,7 +833,8 @@ extension Option {
   public static let scannerOutputDir: Option = Option("-scanner-output-dir", .separate, attributes: [.helpHidden, .frontend, .noDriver], helpText: "Directory for generated files from swift dependency scanner")
   public static let scannerPrefixMapSdk: Option = Option("-scanner-prefix-map-sdk", .separate, attributes: [], metaVar: "<path>", helpText: "Remap paths within SDK reported by dependency scanner")
   public static let scannerPrefixMapToolchain: Option = Option("-scanner-prefix-map-toolchain", .separate, attributes: [], metaVar: "<path>", helpText: "Remap paths within toolchain directory reported by dependency scanner")
-  public static let scannerPrefixMap: Option = Option("-scanner-prefix-map", .separate, attributes: [.frontend], metaVar: "<prefix=replacement>", helpText: "Remap paths reported by dependency scanner")
+  public static let scannerPrefixMap: Option = Option("-scanner-prefix-map", .separate, attributes: [], metaVar: "<prefix=replacement>", helpText: "Remap paths reported by dependency scanner")
+  public static let scannerPrefixMapPaths: Option = Option("-scanner-prefix-map-paths", .multiArg, attributes: [.frontend], metaVar: "<prefix> <replacement>", helpText: "Remap paths reported by dependency scanner", numArgs: 2)
   public static let sdkModuleCachePath: Option = Option("-sdk-module-cache-path", .separate, attributes: [.frontend, .doesNotAffectIncrementalBuild, .argumentIsPath], helpText: "Specifies the module cache path for explicitly-built SDK modules")
   public static let sdk: Option = Option("-sdk", .separate, attributes: [.frontend, .synthesizeInterface, .argumentIsPath], metaVar: "<sdk>", helpText: "Compile against <sdk>")
   public static let serializeBreakingChangesPath: Option = Option("-serialize-breaking-changes-path", .separate, attributes: [.noInteractive, .argumentIsPath], metaVar: "<path>", helpText: "Serialize breaking changes found by the API digester to <path>")
@@ -1801,6 +1802,7 @@ extension Option {
       Option.scannerPrefixMapSdk,
       Option.scannerPrefixMapToolchain,
       Option.scannerPrefixMap,
+      Option.scannerPrefixMapPaths,
       Option.sdkModuleCachePath,
       Option.sdk,
       Option.serializeBreakingChangesPath,

Tests/SwiftDriverTests/CachingBuildTests.swift

@@ -895,16 +895,17 @@ final class CachingBuildTests: XCTestCase {
                                      main.nativePathString(escaped: true)] + sdkArgumentsForTesting,
                               env: env,
                               interModuleDependencyOracle: dependencyOracle)
-      guard driver.isFrontendArgSupported(.scannerPrefixMap) else {
+      guard driver.isFrontendArgSupported(.scannerPrefixMapPaths) else {
         throw XCTSkip("frontend doesn't support prefix map")
       }
       let scanLibPath = try XCTUnwrap(driver.getSwiftScanLibPath())
       try dependencyOracle.verifyOrCreateScannerInstance(swiftScanLibPath: scanLibPath)
       let resolver = try ArgsResolver(fileSystem: localFileSystem)
       let scannerCommand = try driver.dependencyScannerInvocationCommand().1.map { try resolver.resolve($0) }
 
-      XCTAssertTrue(scannerCommand.contains("-scanner-prefix-map"))
-      XCTAssertTrue(scannerCommand.contains(try testInputsPath.description + "=/^src"))
+      XCTAssertTrue(scannerCommand.contains("-scanner-prefix-map-paths"))
+      XCTAssertTrue(scannerCommand.contains(try testInputsPath.description))
+      XCTAssertTrue(scannerCommand.contains("/^src"))
 
       let jobs = try driver.planBuild()
       for job in jobs {