Frontend: Obsolete -fixit-all and -emit-fixits-path

With `ARCMigrate` and `arcmt-test` removed from clang in
llvm/llvm-project#119269 and the new code
migration experience under way (see
swiftlang/swift-evolution#2673), these options
are no longer relevant nor known to be in use. They were introduced
long ago to support automatic code migration up to Swift 4.

For now, turn them into a no-op and emit a obsoletion warning.

Author: AnthonyLatsis

include/swift/AST/DiagnosticsFrontend.def

@@ -193,6 +193,8 @@ ERROR(cannot_emit_ir_skipping_function_bodies,none,
 WARNING(emit_reference_dependencies_without_primary_file,none,
         "ignoring -emit-reference-dependencies (requires -primary-file)", ())
 
+WARNING(ignoring_option_obsolete,none,
+        "ignoring '%0'; this option is obsolete", (StringRef))
 WARNING(ignoring_option_requires_option,none,
         "ignoring %0 (requires %1)", (StringRef, StringRef))
 WARNING(warn_ignore_option_overriden_by,none,

lib/Frontend/ArgsToFrontendOutputsConverter.cpp

@@ -317,8 +317,6 @@ SupplementaryOutputPathsComputer::getSupplementaryOutputPathsFromArguments()
       options::OPT_emit_reference_dependencies_path);
   auto serializedDiagnostics = getSupplementaryFilenamesFromArguments(
       options::OPT_serialize_diagnostics_path);
-  auto fixItsOutput = getSupplementaryFilenamesFromArguments(
-      options::OPT_emit_fixits_path);
   auto loadedModuleTrace = getSupplementaryFilenamesFromArguments(
       options::OPT_emit_loaded_module_trace_path);
   auto TBD = getSupplementaryFilenamesFromArguments(options::OPT_emit_tbd_path);
@@ -343,7 +341,7 @@ SupplementaryOutputPathsComputer::getSupplementaryOutputPathsFromArguments()
       options::OPT_save_optimization_record_path);
   if (!clangHeaderOutput || !moduleOutput || !moduleDocOutput ||
       !dependenciesFile || !referenceDependenciesFile ||
-      !serializedDiagnostics || !fixItsOutput || !loadedModuleTrace || !TBD ||
+      !serializedDiagnostics || !loadedModuleTrace || !TBD ||
       !moduleInterfaceOutput || !privateModuleInterfaceOutput || !packageModuleInterfaceOutput ||
       !moduleSourceInfoOutput || !moduleSummaryOutput || !abiDescriptorOutput ||
       !moduleSemanticInfoOutput || !optRecordOutput) {
@@ -361,7 +359,6 @@ SupplementaryOutputPathsComputer::getSupplementaryOutputPathsFromArguments()
     sop.DependenciesFilePath = (*dependenciesFile)[i];
     sop.ReferenceDependenciesFilePath = (*referenceDependenciesFile)[i];
     sop.SerializedDiagnosticsPath = (*serializedDiagnostics)[i];
-    sop.FixItsOutputPath = (*fixItsOutput)[i];
     sop.LoadedModuleTracePath = (*loadedModuleTrace)[i];
     sop.TBDPath = (*TBD)[i];
     sop.ModuleInterfaceOutputPath = (*moduleInterfaceOutput)[i];

lib/Frontend/CompilerInvocation.cpp

@@ -2548,7 +2548,20 @@ static bool ParseDiagnosticArgs(DiagnosticOptions &Opts, ArgList &Args,
       Opts.EmitMacroExpansionFiles = !negated;
   }
 
-  Opts.FixitCodeForAllDiagnostics |= Args.hasArg(OPT_fixit_all);
+  {
+    OptSpecifier obsoleteOpts[] = {
+      OPT_fixit_all,
+      OPT_emit_fixits_path,
+    };
+
+    for (auto option: obsoleteOpts) {
+      if (auto *arg = Args.getLastArg(option)) {
+        Diags.diagnose(SourceLoc(), diag::ignoring_option_obsolete,
+                       arg->getOption().getPrefixedName());
+      }
+    }
+  }
+
   Opts.SuppressWarnings |= Args.hasArg(OPT_suppress_warnings);
   Opts.SuppressRemarks |= Args.hasArg(OPT_suppress_remarks);
   for (const Arg *arg : Args.filtered(OPT_warning_treating_Group)) {

test/FixCode/batch-mode.swift

@@ -0,0 +1,5 @@
+// RUN: %empty-directory(%t)
+// RUN: %target-swift-frontend -typecheck -fixit-all -emit-fixits-path %t.remap %s 2>&1 | %FileCheck %s
+
+// CHECK: <unknown>:0: warning: ignoring '-fixit-all'; this option is obsolete
+// CHECK: <unknown>:0: warning: ignoring '-emit-fixits-path'; this option is obsolete