[Test Only] Adapt 'testExplicitLinkLibraries' to use opt-in scanner validation mehanism on supporting compilers

Author: artemcm

Sources/SwiftOptions/Options.swift

@@ -745,6 +745,7 @@ extension Option {
   public static let saveOptimizationRecord: Option = Option("-save-optimization-record", .flag, attributes: [.frontend], helpText: "Generate a YAML optimization record file")
   public static let saveTemps: Option = Option("-save-temps", .flag, attributes: [.noInteractive, .doesNotAffectIncrementalBuild], helpText: "Save intermediate compilation results")
   public static let scanDependencies: Option = Option("-scan-dependencies", .flag, attributes: [.frontend, .noInteractive, .doesNotAffectIncrementalBuild], helpText: "Scan dependencies of the given Swift sources", group: .modes)
+  public static let scannerModuleValidation: Option = Option("-scanner-module-validation", .flag, attributes: [.helpHidden, .frontend, .noDriver], helpText: "Validate binary modules in the 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")
@@ -1616,6 +1617,7 @@ extension Option {
       Option.saveOptimizationRecord,
       Option.saveTemps,
       Option.scanDependencies,
+      Option.scannerModuleValidation,
       Option.scannerPrefixMapSdk,
       Option.scannerPrefixMapToolchain,
       Option.scannerPrefixMap,

Tests/SwiftDriverTests/ExplicitModuleBuildTests.swift

@@ -374,12 +374,18 @@ final class ExplicitModuleBuildTests: XCTestCase {
         throw XCTSkip("libSwiftScan does not support link library reporting.")
       }
 
-      var driver = try Driver(args: ["swiftc",
-                                     "-I", cHeadersPath.nativePathString(escaped: true),
-                                     "-I", swiftModuleInterfacesPath.nativePathString(escaped: true),
-                                     "-explicit-module-build",
-                                     "-import-objc-header", bridgingHeaderpath.nativePathString(escaped: true),
-                                     main.nativePathString(escaped: true)] + sdkArgumentsForTesting)
+      var args = ["swiftc",
+                  "-I", cHeadersPath.nativePathString(escaped: true),
+                  "-I", swiftModuleInterfacesPath.nativePathString(escaped: true),
+                  "-explicit-module-build",
+                  "-import-objc-header", bridgingHeaderpath.nativePathString(escaped: true),
+                  main.nativePathString(escaped: true)] + sdkArgumentsForTesting
+      var driver = try Driver(args: args)
+      // If this is a supported flow, then it is currently required for this test
+      if driver.isFrontendArgSupported(.scannerModuleValidation) {
+        driver = try Driver(args: args + ["-scanner-module-validation"])
+      }
+
       let _ = try driver.planBuild()
       let dependencyGraph = try XCTUnwrap(driver.explicitDependencyBuildPlanner?.dependencyGraph)