Merge pull request #627 from nkcsgexi/pass-down-user-module-ver

Pass-down -user-module-version to compiler if the compiler supports it

Author: nkcsgexi

Sources/SwiftDriver/Driver/Driver.swift

@@ -329,6 +329,20 @@ public struct Driver {
       .appending(component: "Frameworks")
   } ()
 
+  public func isFrontendArgSupported(_ opt: Option) -> Bool {
+    var current = opt.spelling
+    while(true) {
+      if supportedFrontendFlags.contains(current) {
+        return true
+      }
+      if current.starts(with: "-") {
+        current = String(current.dropFirst())
+      } else {
+        return false
+      }
+    }
+  }
+
   /// Handler for emitting diagnostics to stderr.
   public static let stderrDiagnosticsHandler: DiagnosticsEngine.DiagnosticsHandler = { diagnostic in
     stdErrQueue.sync {

Sources/SwiftDriver/Jobs/FrontendJobHelpers.swift

@@ -180,6 +180,14 @@ extension Driver {
     try commandLine.appendAllArguments(.Xfrontend, from: &parsedOptions)
     try commandLine.appendAll(.coveragePrefixMap, from: &parsedOptions)
 
+    // Pass down -user-module-version if we are working with a compiler that
+    // supports it.
+    if let ver = parsedOptions.getLastArgument(.userModuleVersion)?.asSingle,
+       isFrontendArgSupported(.userModuleVersion) {
+      commandLine.appendFlag(.userModuleVersion)
+      commandLine.appendFlag(ver)
+    }
+
     if let workingDirectory = workingDirectory {
       // Add -Xcc -working-directory before any other -Xcc options to ensure it is
       // overridden by an explicit -Xcc -working-directory, although having a

Tests/SwiftDriverTests/SwiftDriverTests.swift

@@ -3617,6 +3617,21 @@ final class SwiftDriverTests: XCTestCase {
     }
   }
 
+  func testUserModuleVersion() throws {
+    do {
+      var driver = try Driver(args: ["swiftc", "foo.swift", "-emit-module", "-module-name",
+                                     "foo", "-user-module-version", "12.21"])
+      let plannedJobs = try driver.planBuild()
+      XCTAssertEqual(plannedJobs.count, 2)
+      let compileJob = plannedJobs[0]
+      let mergeJob = plannedJobs[1]
+      XCTAssertEqual(compileJob.kind, .compile)
+      XCTAssertEqual(mergeJob.kind, .mergeModule)
+      XCTAssertTrue(mergeJob.commandLine.contains(.flag("-user-module-version")))
+      XCTAssertTrue(mergeJob.commandLine.contains(.flag("12.21")))
+    }
+  }
+
   func testVerifyEmittedInterfaceJob() throws {
     // Evolution enabled
     do {