Teach swift-driver to emit private interfaces

Sources/SwiftDriver/Driver/Driver.swift

@@ -239,6 +239,9 @@ public struct Driver {
  /// Path to the Swift interface file.
  let swiftInterfacePath: VirtualPath?
 
+ /// Path to the Swift private interface file.
+ let swiftPrivateInterfacePath: VirtualPath?
+
  /// Path to the optimization record.
  let optimizationRecordPath: VirtualPath?
 
@@ -521,6 +524,14 @@ public struct Driver {
  outputFileMap: self.outputFileMap,
  moduleName: moduleOutputInfo.name)
 
+ self.swiftPrivateInterfacePath = try Self.computeSupplementaryOutputPath(
+ &parsedOptions, type: .privateSwiftInterface, isOutputOptions: [],
+ outputPath: .emitPrivateModuleInterfacePath,
+ compilerOutputType: compilerOutputType,
+ compilerMode: compilerMode,
+ outputFileMap: self.outputFileMap,
+ moduleName: moduleOutputInfo.name)
+
  var optimizationRecordFileType = FileType.yamlOptimizationRecord
  if let argument = parsedOptions.getLastArgument(.saveOptimizationRecordEQ)?.asSingle {
  switch argument {
@@ -1576,7 +1587,8 @@ extension Driver {
  moduleOutputKind = .auxiliary
  } else if compilerMode != .singleCompile &&
  parsedOptions.hasArgument(.emitObjcHeader, .emitObjcHeaderPath,
- .emitModuleInterface, .emitModuleInterfacePath) {
+ .emitModuleInterface, .emitModuleInterfacePath,
+ .emitPrivateModuleInterfacePath) {
  // An option has been passed which requires whole-module knowledge, but we
  // don't have that. Generate a module, but treat it as an intermediate
  // output.

Sources/SwiftDriver/Jobs/EmitModuleJob.swift

@@ -29,6 +29,7 @@ extension Driver {
  addSupplementalOutput(path: moduleDocOutputPath, flag: "-emit-module-doc-path", type: .swiftDocumentation)
  addSupplementalOutput(path: moduleSourceInfoPath, flag: "-emit-module-source-info-path", type: .swiftSourceInfoFile)
  addSupplementalOutput(path: swiftInterfacePath, flag: "-emit-module-interface-path", type: .swiftInterface)
+ addSupplementalOutput(path: swiftPrivateInterfacePath, flag: "-emit-private-module-interface-path", type: .privateSwiftInterface)
  addSupplementalOutput(path: objcGeneratedHeaderPath, flag: "-emit-objc-header-path", type: .objcHeader)
  addSupplementalOutput(path: tbdPath, flag: "-emit-tbd-path", type: .tbd)
 

Sources/SwiftDriver/Jobs/FrontendJobHelpers.swift

@@ -362,6 +362,12 @@ extension Driver {
  input: nil,
  flag: "-emit-module-interface-path")
 
+ addOutputOfType(
+ outputType: .privateSwiftInterface,
+ finalOutputPath: swiftPrivateInterfacePath,
+ input: nil,
+ flag: "-emit-private-module-interface-path")
+
  addOutputOfType(
  outputType: .tbd,
  finalOutputPath: tbdPath,

Tests/SwiftDriverTests/SwiftDriverTests.swift

@@ -1376,16 +1376,18 @@ final class SwiftDriverTests: XCTestCase {
  }
 
  func testSingleThreadedWholeModuleOptimizationCompiles() throws {
- var driver1 = try Driver(args: ["swiftc", "-whole-module-optimization", "foo.swift", "bar.swift", "-module-name", "Test", "-target", "x86_64-apple-macosx10.15", "-emit-module-interface", "-emit-objc-header-path", "Test-Swift.h"])
+ var driver1 = try Driver(args: ["swiftc", "-whole-module-optimization", "foo.swift", "bar.swift", "-module-name", "Test", "-target", "x86_64-apple-macosx10.15", "-emit-module-interface", "-emit-objc-header-path", "Test-Swift.h", "-emit-private-module-interface-path", "Test.private.swiftinterface"])
  let plannedJobs = try driver1.planBuild()
  XCTAssertEqual(plannedJobs.count, 2)
  XCTAssertEqual(plannedJobs[0].kind, .compile)
- XCTAssertEqual(plannedJobs[0].outputs.count, 3)
+ XCTAssertEqual(plannedJobs[0].outputs.count, 4)
  XCTAssertEqual(plannedJobs[0].outputs[0].file, VirtualPath.temporary(RelativePath("Test.o")))
  XCTAssertEqual(plannedJobs[0].outputs[1].file, VirtualPath.relative(RelativePath("Test-Swift.h")))
  XCTAssertEqual(plannedJobs[0].outputs[2].file, VirtualPath.relative(RelativePath("Test.swiftinterface")))
+ XCTAssertEqual(plannedJobs[0].outputs[3].file, VirtualPath.relative(RelativePath("Test.private.swiftinterface")))
  XCTAssert(!plannedJobs[0].commandLine.contains(.flag("-primary-file")))
  XCTAssert(plannedJobs[0].commandLine.contains(.flag("-emit-module-interface-path")))
+ XCTAssert(plannedJobs[0].commandLine.contains(.flag("-emit-private-module-interface-path")))
 
  XCTAssertEqual(plannedJobs[1].kind, .link)
  }