Merge pull request #518 from porglezomp-misc/swift-driver-integration-tests-you-know-the-root-already

[Integration Tests] Calculate the swiftRootDir more accurately

Author: porglezomp

Tests/SwiftDriverTests/IntegrationTests.swift

@@ -149,14 +149,17 @@ final class IntegrationTests: IntegrationTestCase {
         return
       }
 
+      /// The root directory, where build/, llvm-project/, and swift/ live.
+      let swiftRootDir = packageDirectory.parentDirectory
+
       // SWIFT_DRIVER_LIT_DIR may be relative or absolute. If it's
       // relative, it's relative to the parent directory of the package. If
       // you've cloned this package into a Swift compiler working directory,
       // that means it'll be the directory with build/, llvm/, swift/, and
       // swift-driver/ in it.
       let litConfigDir = AbsolutePath(
         litConfigPathString,
-        relativeTo: packageDirectory.parentDirectory
+        relativeTo: swiftRootDir
       )
 
       /// The site config file to use.
@@ -168,9 +171,6 @@ final class IntegrationTests: IntegrationTestCase {
       /// The path to the real frontend we should use.
       let frontendFile = swiftBuildDir.appending(components: "bin", "swift")
 
-      /// The root directory, where build/, llvm-project/, and swift/ live.
-      let swiftRootDir = swiftBuildDir.parentDirectory.parentDirectory.parentDirectory
-
       /// The path to lit.py.
       let litFile = swiftRootDir.appending(components: "llvm-project", "llvm", "utils", "lit",
                                              "lit.py")