From e0dd9a84836870e1fd0d07b7b8970ede017263a2 Mon Sep 17 00:00:00 2001
From: Allan Shortlidge <shortlidge@apple.com>
Date: Sat, 19 Aug 2023 23:20:29 -0700
Subject: [PATCH] Pass -experimental-lazy-typecheck to -emit-module jobs.

Resolves rdar://114203755
---
 Sources/SwiftDriver/Driver/Driver.swift       |  4 ++--
 Sources/SwiftDriver/Jobs/EmitModuleJob.swift  |  3 +++
 Sources/SwiftOptions/Option.swift             |  2 +-
 Sources/SwiftOptions/Options.swift            |  1 +
 Tests/SwiftDriverTests/SwiftDriverTests.swift | 12 ++++++++++++
 5 files changed, 19 insertions(+), 3 deletions(-)

diff --git a/Sources/SwiftDriver/Driver/Driver.swift b/Sources/SwiftDriver/Driver/Driver.swift
index 21a0dd410..21af10e04 100644
--- a/Sources/SwiftDriver/Driver/Driver.swift
+++ b/Sources/SwiftDriver/Driver/Driver.swift
@@ -2092,8 +2092,8 @@ extension Driver {
       case .indexFile:
         compilerOutputType = .indexData
 
-      case .parse, .resolveImports, .typecheck, .dumpParse,
-           .printAst, .dumpTypeRefinementContexts, .dumpScopeMaps,
+      case .parse, .resolveImports, .typecheck, .experimentalLazyTypecheck,
+           .dumpParse, .printAst, .dumpTypeRefinementContexts, .dumpScopeMaps,
            .dumpInterfaceHash, .dumpTypeInfo, .verifyDebugInfo:
         compilerOutputType = nil
 
diff --git a/Sources/SwiftDriver/Jobs/EmitModuleJob.swift b/Sources/SwiftDriver/Jobs/EmitModuleJob.swift
index 42d7224fa..c1d4d4fb1 100644
--- a/Sources/SwiftDriver/Jobs/EmitModuleJob.swift
+++ b/Sources/SwiftDriver/Jobs/EmitModuleJob.swift
@@ -106,6 +106,9 @@ extension Driver {
     try commandLine.appendLast(.emitExtensionBlockSymbols, .omitExtensionBlockSymbols, from: &parsedOptions)
     try commandLine.appendLast(.symbolGraphMinimumAccessLevel, from: &parsedOptions)
     try commandLine.appendLast(.checkApiAvailabilityOnly, from: &parsedOptions)
+    if isFrontendArgSupported(.experimentalLazyTypecheck) {
+      try commandLine.appendLast(.experimentalLazyTypecheck, from: &parsedOptions)
+    }
 
     if parsedOptions.hasArgument(.parseAsLibrary, .emitLibrary) {
       commandLine.appendFlag(.parseAsLibrary)
diff --git a/Sources/SwiftOptions/Option.swift b/Sources/SwiftOptions/Option.swift
index 5535d8b6f..c63ac08bf 100644
--- a/Sources/SwiftOptions/Option.swift
+++ b/Sources/SwiftOptions/Option.swift
@@ -59,7 +59,7 @@ public struct Option {
   /// The spelling of the option, including any leading dashes.
   public let spelling: String
 
-  ///. The kind of option, which determines how it is parsed.
+  /// The kind of option, which determines how it is parsed.
   public let kind: Kind
 
   /// The option that this aliases, if any, as a closure that produces the
diff --git a/Sources/SwiftOptions/Options.swift b/Sources/SwiftOptions/Options.swift
index 72805e4ee..201961f16 100644
--- a/Sources/SwiftOptions/Options.swift
+++ b/Sources/SwiftOptions/Options.swift
@@ -1239,6 +1239,7 @@ extension Option {
       Option.ExperimentalPerformanceAnnotations,
       Option.platformCCallingConventionEQ,
       Option.platformCCallingConvention,
+      Option.experimentalLazyTypecheck,
       Option.experimentalPrintFullConvention,
       Option.experimentalSkipAllFunctionBodies,
       Option.experimentalSkipNonInlinableFunctionBodiesWithoutTypes,
diff --git a/Tests/SwiftDriverTests/SwiftDriverTests.swift b/Tests/SwiftDriverTests/SwiftDriverTests.swift
index cdddb413e..bf28891bc 100644
--- a/Tests/SwiftDriverTests/SwiftDriverTests.swift
+++ b/Tests/SwiftDriverTests/SwiftDriverTests.swift
@@ -7227,6 +7227,18 @@ final class SwiftDriverTests: XCTestCase {
       ]))
     }
   }
+
+  func testEmitModuleExperimentalLazyTypecheck() throws {
+    var driver = try Driver(args: [
+      "swiftc", "test.swift", "-module-name", "Test", "-experimental-lazy-typecheck", "-emit-module-interface"
+    ])
+    guard driver.isFrontendArgSupported(.experimentalLazyTypecheck) else {
+      throw XCTSkip("Skipping: compiler does not support '-experimental-lazy-typecheck'")
+    }
+    let jobs = try driver.planBuild().removingAutolinkExtractJobs()
+    let emitModuleJob = try XCTUnwrap(jobs.first(where: {$0.kind == .emitModule}))
+    XCTAssertTrue(emitModuleJob.commandLine.contains(.flag("-experimental-lazy-typecheck")))
+  }
 }
 
 func assertString(