[Sema] Intro flag to promote to an error missing explicit availability

Author: xymus

include/swift/AST/DiagnosticsFrontend.def

@@ -48,6 +48,11 @@ ERROR(error_unknown_library_level, none,
       "unknown library level '%0', "
       "expected one of 'api', 'spi' or 'other'", (StringRef))
 
+ERROR(error_unknown_require_explicit_availability, none,
+      "unknown argument '%0', passed to -require-explicit-availability, "
+      "expected 'error', 'warn' or 'ignore'",
+      (StringRef))
+
 ERROR(error_unsupported_opt_for_target, none,
       "unsupported option '%0' for target '%1'", (StringRef, StringRef))
 

include/swift/AST/DiagnosticsSema.def

@@ -5749,9 +5749,9 @@ ERROR(availability_protocol_requires_version,
 NOTE(availability_protocol_requirement_here, none,
      "protocol requirement here", ())
 
-WARNING(public_decl_needs_availability, none,
-        "public declarations should have an availability attribute "
-        "with an introduction version", ())
+ERROR(public_decl_needs_availability, none,
+      "public declarations should have an availability attribute "
+      "with an introduction version", ())
 
 ERROR(attr_requires_decl_availability_for_platform,none,
       "'%0' requires that %1 have explicit availability for %2",

include/swift/Basic/LangOptions.h

@@ -193,8 +193,9 @@ namespace swift {
     /// Enable 'availability' restrictions for App Extensions.
     bool EnableAppExtensionRestrictions = false;
 
-    /// Require public declarations to declare an introduction OS version.
-    bool RequireExplicitAvailability = false;
+    /// Diagnostic level to report when a public declarations doesn't declare
+    /// an introduction OS version.
+    Optional<DiagnosticBehavior> RequireExplicitAvailability = None;
 
     /// Introduction platform and version to suggest as fix-it
     /// when using RequireExplicitAvailability.

include/swift/Option/Options.td

@@ -411,7 +411,13 @@ def enable_library_evolution : Flag<["-"], "enable-library-evolution">,
 
 def require_explicit_availability : Flag<["-"], "require-explicit-availability">,
   Flags<[FrontendOption, NoInteractiveOption]>,
-  HelpText<"Require explicit availability on public declarations">;
+  HelpText<"Warn on public declarations without an availability attribute">;
+
+def require_explicit_availability_EQ : Joined<["-"], "require-explicit-availability=">,
+  MetaVarName<"<error,warn,ignore>">,
+  Flags<[FrontendOption, NoInteractiveOption]>,
+  HelpText<"Set diagnostic level to report public declarations without an availability attribute">;
+
 def require_explicit_availability_target : Separate<["-"], "require-explicit-availability-target">,
   Flags<[FrontendOption, NoInteractiveOption]>,
   HelpText<"Suggest fix-its adding @available(<target>, *) to public declarations without availability">,

lib/Driver/ToolChains.cpp

@@ -241,6 +241,7 @@ void ToolChain::addCommonFrontendArgs(const OutputInfo &OI,
   inputArgs.AddLastArg(arguments, options::OPT_enable_library_evolution);
   inputArgs.AddLastArg(arguments, options::OPT_require_explicit_availability);
   inputArgs.AddLastArg(arguments, options::OPT_require_explicit_availability_target);
+  inputArgs.AddLastArg(arguments, options::OPT_require_explicit_availability_EQ);
   inputArgs.AddLastArg(arguments, options::OPT_require_explicit_sendable);
   inputArgs.AddLastArg(arguments, options::OPT_check_api_availability_only);
   inputArgs.AddLastArg(arguments, options::OPT_enable_testing);

lib/Frontend/CompilerInvocation.cpp

@@ -587,13 +587,6 @@ static bool ParseLangArgs(LangOptions &Opts, ArgList &Args,
   if (Args.getLastArg(OPT_debug_cycles))
     Opts.DebugDumpCycles = true;
 
-  if (Args.getLastArg(OPT_require_explicit_availability, OPT_require_explicit_availability_target)) {
-    Opts.RequireExplicitAvailability = true;
-    if (const Arg *A = Args.getLastArg(OPT_require_explicit_availability_target)) {
-      Opts.RequireExplicitAvailabilityTarget = A->getValue();
-    }
-  }
-
   Opts.RequireExplicitSendable |= Args.hasArg(OPT_require_explicit_sendable);
   for (const Arg *A : Args.filtered(OPT_define_availability)) {
     Opts.AvailabilityMacros.push_back(A->getValue());
@@ -721,6 +714,28 @@ static bool ParseLangArgs(LangOptions &Opts, ArgList &Args,
     }
   }
 
+  if (const Arg *A = Args.getLastArg(OPT_require_explicit_availability_EQ)) {
+    StringRef diagLevel = A->getValue();
+    if (diagLevel == "warn") {
+      Opts.RequireExplicitAvailability = DiagnosticBehavior::Warning;
+    } else if (diagLevel == "error") {
+      Opts.RequireExplicitAvailability = DiagnosticBehavior::Error;
+    } else if (diagLevel == "ignore") {
+      Opts.RequireExplicitAvailability = None;
+    } else {
+      Diags.diagnose(SourceLoc(),
+                     diag::error_unknown_require_explicit_availability,
+                     diagLevel);
+    }
+  } else if (Args.getLastArg(OPT_require_explicit_availability,
+                             OPT_require_explicit_availability_target)) {
+    Opts.RequireExplicitAvailability = DiagnosticBehavior::Warning;
+  }
+
+  if (const Arg *A = Args.getLastArg(OPT_require_explicit_availability_target)) {
+    Opts.RequireExplicitAvailabilityTarget = A->getValue();
+  }
+
   Opts.EnableSPIOnlyImports = Args.hasArg(OPT_experimental_spi_only_imports);
 
   if (Opts.EnableSwift3ObjCInference) {

lib/Sema/TypeCheckAvailability.cpp

@@ -4279,7 +4279,8 @@ static bool declNeedsExplicitAvailability(const Decl *decl) {
 void swift::checkExplicitAvailability(Decl *decl) {
   // Skip if the command line option was not set and
   // accessors as we check the pattern binding decl instead.
-  if (!decl->getASTContext().LangOpts.RequireExplicitAvailability ||
+  auto DiagLevel = decl->getASTContext().LangOpts.RequireExplicitAvailability;
+  if (!DiagLevel ||
       isa<AccessorDecl>(decl))
     return;
 
@@ -4323,6 +4324,7 @@ void swift::checkExplicitAvailability(Decl *decl) {
 
   if (declNeedsExplicitAvailability(decl)) {
     auto diag = decl->diagnose(diag::public_decl_needs_availability);
+    diag.limitBehavior(*DiagLevel);
 
     auto suggestPlatform =
       decl->getASTContext().LangOpts.RequireExplicitAvailabilityTarget;

test/attr/require_explicit_availability.swift

@@ -1,7 +1,25 @@
 // Test the -require-explicit-availability flag
 // REQUIRES: OS=macosx
-
-// RUN: %swiftc_driver -typecheck -parse-as-library -target %target-cpu-apple-macosx10.10 -Xfrontend -verify -require-explicit-availability -require-explicit-availability-target "macOS 10.10"  %s
+// RUN: %empty-directory(%t)
+
+/// Using the flag directly raises warnings and fixits.
+// RUN: %swiftc_driver -typecheck -parse-as-library -Xfrontend -verify %s \
+// RUN:   -target %target-cpu-apple-macosx10.10 -require-explicit-availability \
+// RUN:   -require-explicit-availability-target "macOS 10.10"
+// RUN: %swiftc_driver -typecheck -parse-as-library -Xfrontend -verify %s \
+// RUN:   -target %target-cpu-apple-macosx10.10 -require-explicit-availability=warn \
+// RUN:   -require-explicit-availability-target "macOS 10.10"
+
+/// Upgrade the diagnostic to an error.
+// RUN: sed -e "s/xpected-warning/xpected-error/" < %s > %t/Errors.swift
+// RUN: %target-swift-frontend -typecheck -parse-as-library -verify %t/Errors.swift \
+// RUN:   -target %target-cpu-apple-macosx10.10 -require-explicit-availability=error \
+// RUN:   -require-explicit-availability-target "macOS 10.10"
+
+/// Error on an invalid argument.
+// RUN: not %target-swift-frontend -typecheck %s -require-explicit-availability=NotIt 2>&1 \
+// RUN:   | %FileCheck %s --check-prefix CHECK-ARG
+// CHECK-ARG: error: unknown argument 'NotIt', passed to -require-explicit-availability, expected 'error', 'warn' or 'ignore'
 
 public struct S { // expected-warning {{public declarations should have an availability attribute with an introduction version}}
   public func method() { }