[Frontend] Change -require-explicit-sendable argument to mean -Wwarning ExplicitSendable

Author: xedin

include/swift/Basic/LangOptions.h

@@ -245,9 +245,6 @@ namespace swift {
     // Availability macros definitions to be expanded at parsing.
     SmallVector<std::string, 4> AvailabilityMacros;
 
-    /// Require public declarations to declare that they are Sendable (or not).
-    bool RequireExplicitSendable = false;
-
     /// Detect and automatically import modules' cross-import overlays.
     bool EnableCrossImportOverlays = false;
 

lib/Frontend/CompilerInvocation.cpp

@@ -1272,7 +1272,6 @@ static bool ParseLangArgs(LangOptions &Opts, ArgList &Args,
   if (Args.getLastArg(OPT_debug_cycles))
     Opts.DebugDumpCycles = true;
 
-  Opts.RequireExplicitSendable |= Args.hasArg(OPT_require_explicit_sendable);
   for (const Arg *A : Args.filtered(OPT_define_availability)) {
     Opts.AvailabilityMacros.push_back(A->getValue());
   }
@@ -2724,6 +2723,14 @@ static bool ParseDiagnosticArgs(DiagnosticOptions &Opts, ArgList &Args,
       }
     }());
   }
+
+  // `-require-explicit-sendable` is an alias to `-Wwarning ExplicitSendable`.
+  if (Args.hasArg(OPT_require_explicit_sendable) &&
+      !Args.hasArg(OPT_suppress_warnings)) {
+    Opts.WarningsAsErrorsRules.push_back(WarningAsErrorRule(
+        WarningAsErrorRule::Action::Disable, "ExplicitSendable"));
+  }
+
   if (Args.hasArg(OPT_debug_diagnostic_names)) {
     Opts.PrintDiagnosticNames = PrintDiagnosticNamesMode::Identifier;
   }

test/Concurrency/objc_require_explicit_sendable.swift

@@ -1,6 +1,9 @@
 // RUN: %target-swift-frontend(mock-sdk: %clang-importer-sdk) -emit-sil -o /dev/null -I %S/Inputs/custom-modules %s -verify -parse-as-library -Wwarning ExplicitSendable
 // RUN: %target-swift-frontend(mock-sdk: %clang-importer-sdk) -emit-sil -o /dev/null -I %S/Inputs/custom-modules %s -verify -parse-as-library -Wwarning ExplicitSendable -strict-concurrency=targeted
 // RUN: %target-swift-frontend(mock-sdk: %clang-importer-sdk) -emit-sil -o /dev/null -I %S/Inputs/custom-modules %s -verify -parse-as-library -Wwarning ExplicitSendable -strict-concurrency=complete
+// RUN: %target-swift-frontend(mock-sdk: %clang-importer-sdk) -emit-sil -o /dev/null -I %S/Inputs/custom-modules %s -verify -parse-as-library -require-explicit-sendable
+// RUN: %target-swift-frontend(mock-sdk: %clang-importer-sdk) -emit-sil -o /dev/null -I %S/Inputs/custom-modules %s -verify -parse-as-library -require-explicit-sendable -strict-concurrency=targeted
+// RUN: %target-swift-frontend(mock-sdk: %clang-importer-sdk) -emit-sil -o /dev/null -I %S/Inputs/custom-modules %s -verify -parse-as-library -require-explicit-sendable -strict-concurrency=complete
 
 // REQUIRES: objc_interop
 // REQUIRES: concurrency

test/Concurrency/require-explicit-sendable.swift

@@ -1,5 +1,5 @@
 // RUN: %target-swift-frontend -Wwarning ExplicitSendable -strict-concurrency=complete %s -emit-sil -o /dev/null -verify
-
+// RUN: %target-swift-frontend -require-explicit-sendable -strict-concurrency=complete %s -emit-sil -o /dev/null -verify
 
 public protocol P { }