[Diagnostics] Replace diagnostics' 'DefaultIgnore' option with a corresponding option on diagnostic groups

This brings this control in line with other diagnostic controls we have which operate on a per-group level.
'DefaultIgnoreWarnings' diagnostic group option applies to all warnings belonging to a certain diagnostic group.

The inheritance rules are:
- Marking a diagnostic group as 'DefaultIgnoreWarnings' means warnings belonging to this group will not be emitted by-default
  - Warnings belonging to sub-groups of this group will also not be emitted by-default
- Enabling a 'DefaultIgnoreWarnings' group (with '-Werror','-Wwarning', etc.) means warnings belonging to this group will be emitted.
  - Warnings belonging to sub-groups of this group will also be emitted.
  - Warnings belonging to super-groups of this group will not be affected.

Author: artemcm

include/swift/AST/DefineDiagnosticGroupsMacros.h

@@ -28,10 +28,11 @@
 // Declares a diagnostic group.
 // Parameters:
 //   Name - group name as it appears in DiagGroupID enum and DiagGroupInfo.name
+//   Options - attributes applying to members of this diagnostic group
 //   DocsFile - file with a human readable description for the group located in
 //   userdocs/diagnostic_groups
 #ifndef GROUP
-#define GROUP(Name, DocsFile)
+#define GROUP(Name, Options, DocsFile)
 #endif
 
 // GROUP_LINK macro:

include/swift/AST/DiagnosticEngine.h

@@ -57,7 +57,7 @@ namespace swift {
   /// this enumeration type that uniquely identifies it.
   enum class DiagID : uint32_t;
 
-  enum class DiagGroupID : uint16_t;
+  enum class DiagGroupID : uint32_t;
 
   /// Describes a diagnostic along with its argument types.
   ///
@@ -633,6 +633,9 @@ namespace swift {
     /// escalated to errors.
     llvm::BitVector warningsAsErrors;
 
+    /// Track which diagnostic group (`DiagGroupID`) warnings should be ignored.
+    llvm::BitVector ignoredDiagnosticGroups;
+
     /// Whether a fatal error has occurred
     bool fatalErrorOccurred = false;
 
@@ -642,9 +645,6 @@ namespace swift {
     /// Track the previous emitted Behavior, useful for notes
     DiagnosticBehavior previousBehavior = DiagnosticBehavior::Unspecified;
 
-    /// Track which diagnostics should be ignored.
-    llvm::BitVector ignoredDiagnostics;
-
     friend class DiagnosticStateRAII;
 
   public:
@@ -708,25 +708,31 @@ namespace swift {
       fatalErrorOccurred = false;
     }
 
-    /// Set whether a diagnostic should be ignored.
-    void setIgnoredDiagnostic(DiagID id, bool ignored) {
-      ignoredDiagnostics[(unsigned)id] = ignored;
+    /// Set whether a diagnostic group should be ignored.
+    void setIgnoredDiagnosticGroup(DiagGroupID id, bool ignored) {
+      ignoredDiagnosticGroups[(unsigned)id] = ignored;
     }
 
-    bool isIgnoredDiagnostic(DiagID id) const {
-      return ignoredDiagnostics[(unsigned)id];
+    /// Query whether a specific diagnostic group is ignored.
+    bool isIgnoredDiagnosticGroup(DiagGroupID id) const {
+      return ignoredDiagnosticGroups[(unsigned)id];
     }
+    
+    /// Query whether a specific diagnostic group and *all*
+    /// of its subgroups are ignored.
+    bool isIgnoredDiagnosticGroupTree(DiagGroupID id) const;
 
     void swap(DiagnosticState &other) {
-      std::swap(showDiagnosticsAfterFatalError, other.showDiagnosticsAfterFatalError);
+      std::swap(showDiagnosticsAfterFatalError,
+                other.showDiagnosticsAfterFatalError);
       std::swap(suppressWarnings, other.suppressWarnings);
       std::swap(suppressNotes, other.suppressNotes);
       std::swap(suppressRemarks, other.suppressRemarks);
       std::swap(warningsAsErrors, other.warningsAsErrors);
       std::swap(fatalErrorOccurred, other.fatalErrorOccurred);
       std::swap(anyErrorOccurred, other.anyErrorOccurred);
       std::swap(previousBehavior, other.previousBehavior);
-      std::swap(ignoredDiagnostics, other.ignoredDiagnostics);
+      std::swap(ignoredDiagnosticGroups, other.ignoredDiagnosticGroups);
     }
 
   private:
@@ -966,12 +972,12 @@ namespace swift {
       localization = diag::LocalizationProducer::producerFor(locale, path);
     }
 
-    void ignoreDiagnostic(DiagID id) {
-      state.setIgnoredDiagnostic(id, true);
+    bool isIgnoredDiagnosticGroup(DiagGroupID id) const {
+      return state.isIgnoredDiagnosticGroup(id);
     }
-
-    bool isIgnoredDiagnostic(DiagID id) const {
-      return state.isIgnoredDiagnostic(id);
+    
+    bool isIgnoredDiagnosticGroupTree(DiagGroupID id) const {
+      return state.isIgnoredDiagnosticGroupTree(id);
     }
 
     void resetHadAnyError() {

include/swift/AST/DiagnosticGroups.def

@@ -35,54 +35,56 @@
 #define DEFINE_DIAGNOSTIC_GROUPS_MACROS
 #include "swift/AST/DefineDiagnosticGroupsMacros.h"
 
-// GROUP(Name, DocsFile)
+// GROUP(Name, Options, DocsFile)
 // GROUP_LINK(Parent, Child)
 
-GROUP(no_group, "")
+GROUP(no_group, none, "")
 
-GROUP(ActorIsolatedCall, "actor-isolated-call")
-GROUP(AlwaysAvailableDomain, "always-available-domain")
-GROUP(AvailabilityUnrecognizedName, "availability-unrecognized-name")
-GROUP(ClangDeclarationImport, "clang-declaration-import")
-GROUP(ConformanceIsolation, "conformance-isolation")
-GROUP(DeprecatedDeclaration, "deprecated-declaration")
-GROUP(DynamicCallable, "dynamic-callable-requirements")
-GROUP(EmbeddedRestrictions, "embedded-restrictions")
-GROUP(ErrorInFutureSwiftVersion, "error-in-future-swift-version")
-GROUP(ExclusivityViolation, "exclusivity-violation")
-GROUP(ExistentialAny, "existential-any")
-GROUP(ExistentialMemberAccess, "existential-member-access-limitations")
-GROUP(ImplementationOnlyDeprecated, "implementation-only-deprecated")
-GROUP(IsolatedConformances, "isolated-conformances")
-GROUP(MemberImportVisibility, "member-import-visibility")
-GROUP(MissingModuleOnKnownPaths, "missing-module-on-known-paths")
-GROUP(ModuleNotTestable, "module-not-testable")
-GROUP(ModuleVersionMissing, "module-version-missing")
-GROUP(MultipleInheritance, "multiple-inheritance")
-GROUP(MutableGlobalVariable, "mutable-global-variable")
-GROUP(NominalTypes, "nominal-types")
-GROUP(NonisolatedNonsendingByDefault, "nonisolated-nonsending-by-default")
-GROUP(OpaqueTypeInference, "opaque-type-inference")
-GROUP(PreconcurrencyImport, "preconcurrency-import")
-GROUP(PropertyWrappers, "property-wrapper-requirements")
-GROUP(ProtocolTypeNonConformance, "protocol-type-non-conformance")
-GROUP(ResultBuilderMethods, "result-builder-methods")
-GROUP(SendableClosureCaptures, "sendable-closure-captures")
-GROUP(SendableMetatypes, "sendable-metatypes")
-GROUP(SendingRisksDataRace, "sending-risks-data-race")
-GROUP(StrictLanguageFeatures, "strict-language-features")
-GROUP(StrictMemorySafety, "strict-memory-safety")
-GROUP(StringInterpolationConformance, "string-interpolation-conformance")
-GROUP(TemporaryPointers, "temporary-pointers")
-GROUP(TrailingClosureMatching, "trailing-closure-matching")
-GROUP(UnknownWarningGroup, "unknown-warning-group")
-GROUP(CompilationCaching, "compilation-caching")
-GROUP(WeakMutability, "weak-mutability")
+GROUP(ActorIsolatedCall, none, "actor-isolated-call")
+GROUP(AlwaysAvailableDomain, none, "always-available-domain")
+GROUP(AvailabilityUnrecognizedName, none, "availability-unrecognized-name")
+GROUP(ClangDeclarationImport, none, "clang-declaration-import")
+GROUP(ConformanceIsolation, none, "conformance-isolation")
+GROUP(DeprecatedDeclaration, none, "deprecated-declaration")
+GROUP(DynamicCallable, none, "dynamic-callable-requirements")
+GROUP(EmbeddedRestrictions, DefaultIgnoreWarnings, "embedded-restrictions")
+GROUP(ErrorInFutureSwiftVersion, none, "error-in-future-swift-version")
+GROUP(ExclusivityViolation, none, "exclusivity-violation")
+GROUP(ExistentialAny, none, "existential-any")
+GROUP(ExistentialMemberAccess, none, "existential-member-access-limitations")
+GROUP(ImplementationOnlyDeprecated, none, "implementation-only-deprecated")
+GROUP(IsolatedConformances, none, "isolated-conformances")
+GROUP(MemberImportVisibility, none, "member-import-visibility")
+GROUP(MissingModuleOnKnownPaths, none, "missing-module-on-known-paths")
+GROUP(ModuleNotTestable, none, "module-not-testable")
+GROUP(ModuleVersionMissing, none, "module-version-missing")
+GROUP(MultipleInheritance, none, "multiple-inheritance")
+GROUP(MutableGlobalVariable, none, "mutable-global-variable")
+GROUP(NominalTypes, none, "nominal-types")
+GROUP(NonisolatedNonsendingByDefault, none, "nonisolated-nonsending-by-default")
+GROUP(OpaqueTypeInference, none, "opaque-type-inference")
+GROUP(PreconcurrencyImport, DefaultIgnoreWarnings, "preconcurrency-import")
+GROUP(PropertyWrappers, none, "property-wrapper-requirements")
+GROUP(ProtocolTypeNonConformance, none, "protocol-type-non-conformance")
+GROUP(ResultBuilderMethods, none, "result-builder-methods")
+GROUP(SendableClosureCaptures, none, "sendable-closure-captures")
+GROUP(SendableMetatypes, none, "sendable-metatypes")
+GROUP(SendingRisksDataRace, none, "sending-risks-data-race")
+GROUP(StrictLanguageFeatures, none, "strict-language-features")
+GROUP(UnrecognizedStrictLanguageFeatures, DefaultIgnoreWarnings, "strict-language-features")
+GROUP_LINK(StrictLanguageFeatures, UnrecognizedStrictLanguageFeatures)
+GROUP(StrictMemorySafety, none, "strict-memory-safety")
+GROUP(StringInterpolationConformance, none, "string-interpolation-conformance")
+GROUP(TemporaryPointers, none, "temporary-pointers")
+GROUP(TrailingClosureMatching, none, "trailing-closure-matching")
+GROUP(UnknownWarningGroup, none, "unknown-warning-group")
+GROUP(CompilationCaching, none, "compilation-caching")
+GROUP(WeakMutability, none, "weak-mutability")
 
-GROUP(PerformanceHints, "performance-hints")
-GROUP(ReturnTypeImplicitCopy, "return-type-implicit-copy")
+GROUP(PerformanceHints, DefaultIgnoreWarnings, "performance-hints")
+GROUP(ReturnTypeImplicitCopy, none, "return-type-implicit-copy")
 GROUP_LINK(PerformanceHints, ReturnTypeImplicitCopy)
-GROUP(ExistentialType, "existential-type")
+GROUP(ExistentialType, none, "existential-type")
 GROUP_LINK(PerformanceHints, ExistentialType)
 
 #define UNDEFINE_DIAGNOSTIC_GROUPS_MACROS

include/swift/AST/DiagnosticGroups.h

@@ -24,16 +24,25 @@
 #include <unordered_map>
 
 namespace swift {
+enum class DiagnosticGroupOptions {
+  /// No options.
+  none,
+
+  /// The diagnostic warnings belonging to this group should be ignored by default,
+  /// but will be re-enabled by various warning options (-Wwarning, -Werror).
+  DefaultIgnoreWarnings,
+};
+
 enum class DiagID : uint32_t;
 
-enum class DiagGroupID : uint16_t {
-#define GROUP(Name, Version) Name,
+enum class DiagGroupID : uint32_t {
+#define GROUP(Name, Options, Version) Name,
 #include "swift/AST/DiagnosticGroups.def"
 };
 
 constexpr const auto DiagGroupsCount = [] {
   size_t count = 0;
-#define GROUP(Name, Version) ++count;
+#define GROUP(Name, Options, Version) ++count;
 #include "DiagnosticGroups.def"
   return count;
 }();
@@ -45,9 +54,29 @@ struct DiagGroupInfo {
   llvm::ArrayRef<DiagGroupID> supergroups;
   llvm::ArrayRef<DiagGroupID> subgroups;
   llvm::ArrayRef<DiagID> diagnostics;
+  bool defaultIgnoreWarnings : 1;
+
+  constexpr DiagGroupInfo(DiagGroupID groupID, std::string_view name,
+                          std::string_view documentationFile,
+                          llvm::ArrayRef<DiagGroupID> supergroups,
+                          llvm::ArrayRef<DiagGroupID> subgroups,
+                          llvm::ArrayRef<DiagID> diagnostics,
+                          bool defaultIgnoreWarnings)
+  : id(groupID), name(name), supergroups(supergroups), subgroups(subgroups),
+    diagnostics(diagnostics), defaultIgnoreWarnings(defaultIgnoreWarnings) {}
+
+  constexpr DiagGroupInfo(DiagGroupID groupID, std::string_view name,
+                          std::string_view documentationFile,
+                          DiagnosticGroupOptions opts,
+                          llvm::ArrayRef<DiagGroupID> supergroups,
+                          llvm::ArrayRef<DiagGroupID> subgroups,
+                          llvm::ArrayRef<DiagID> diagnostics)
+  : DiagGroupInfo(groupID, name, documentationFile, supergroups,
+                  subgroups, diagnostics,
+                  opts == DiagnosticGroupOptions::DefaultIgnoreWarnings) {}
 
   void traverseDepthFirst(
-      llvm::function_ref<void(const DiagGroupInfo &)> func) const;
+      llvm::function_ref<void(const DiagGroupInfo &)> func) const;  
 };
 
 extern const std::array<DiagGroupInfo, DiagGroupsCount> diagnosticGroupsInfo;

include/swift/AST/DiagnosticsFrontend.def

@@ -40,12 +40,12 @@ WARNING(warning_upcoming_feature_on_by_default, none,
         "upcoming feature '%0' is already enabled as of Swift version %1",
         (StringRef, unsigned))
 
-GROUPED_WARNING(unrecognized_feature, StrictLanguageFeatures, DefaultIgnore,
+GROUPED_WARNING(unrecognized_feature, UnrecognizedStrictLanguageFeatures, none,
                 "'%0' is not a recognized "
                 "%select{experimental|upcoming}1 feature",
                 (StringRef, bool))
 
-GROUPED_WARNING(feature_not_experimental, StrictLanguageFeatures, DefaultIgnore,
+GROUPED_WARNING(feature_not_experimental, UnrecognizedStrictLanguageFeatures, none,
                 "'%0' is not an experimental feature, "
                 "use -%select{disable|enable}1-upcoming-feature instead",
                 (StringRef, bool))

include/swift/AST/DiagnosticsSema.def

@@ -2842,7 +2842,7 @@ WARNING(add_predates_concurrency_import,none,
      "'Sendable'-related %select{warnings|errors}0 from module %1"
      "%select{| as warnings}0", (bool, Identifier))
 GROUPED_WARNING(remove_predates_concurrency_import,PreconcurrencyImport,
-                DefaultIgnore,
+                none,
                 "'@preconcurrency' on module %0 has no effect", (Identifier))
 WARNING(remove_public_import,none,
         "public import of %0 was not used in public declarations or inlinable code",
@@ -8645,18 +8645,18 @@ GROUPED_ERROR(weak_unowned_in_embedded_swift, EmbeddedRestrictions, none,
               (ReferenceOwnership))
 
 GROUPED_WARNING(untyped_throws_in_embedded_swift, EmbeddedRestrictions,
-                DefaultIgnore,
+                none,
                 "untyped throws is not available in Embedded Swift; add a thrown error type with '(type)'", ())
 GROUPED_WARNING(generic_nonfinal_in_embedded_swift, EmbeddedRestrictions,
-                DefaultIgnore,
+                none,
                 "generic %kind0 in a class %select{must be 'final'|cannot be 'required'}1 in Embedded Swift",
                 (const Decl *, bool))
 GROUPED_WARNING(use_generic_member_of_existential_in_embedded_swift,
-                EmbeddedRestrictions, DefaultIgnore,
+                EmbeddedRestrictions, none,
                 "cannot use generic %kind0 on a value of type %1 in Embedded Swift",
                 (const Decl *, Type))
 GROUPED_WARNING(dynamic_cast_involving_protocol_in_embedded_swift,
-                EmbeddedRestrictions, DefaultIgnore,
+                EmbeddedRestrictions, none,
                 "cannot perform a dynamic cast to a type involving %kind0 in Embedded Swift",
                 (const Decl *))
 
@@ -8975,33 +8975,33 @@ ERROR(conformance_repression_only_on_struct_class_enum,none,
 // MARK: Swift Performance hints
 //===----------------------------------------------------------------------===//
 
-GROUPED_WARNING(perf_hint_function_returns_array,ReturnTypeImplicitCopy,DefaultIgnore,
+GROUPED_WARNING(perf_hint_function_returns_array,ReturnTypeImplicitCopy,none,
                 "Performance: %0 returns a%select{ dictionary|n array}1, leading to implicit copies. "
                 "Consider using an 'inout' parameter instead.", (const FuncDecl *, bool))
-GROUPED_WARNING(perf_hint_closure_returns_array,ReturnTypeImplicitCopy,DefaultIgnore,
+GROUPED_WARNING(perf_hint_closure_returns_array,ReturnTypeImplicitCopy,none,
                 "Performance: closure returns a%select{ dictionary|n array}0, leading to implicit copies. "
                 "Consider using an 'inout' parameter instead.", (bool))
 
-GROUPED_WARNING(perf_hint_param_expects_existential,ExistentialType,DefaultIgnore,
+GROUPED_WARNING(perf_hint_param_expects_existential,ExistentialType,none,
                 "Performance: %0 expects an existential, leading to heap allocation, reference counting, "
                 "and dynamic dispatch. Consider using generic constraints or concrete types instead.",
                 (const ParamDecl*))
-GROUPED_WARNING(perf_hint_func_returns_existential,ExistentialType,DefaultIgnore,
+GROUPED_WARNING(perf_hint_func_returns_existential,ExistentialType,none,
                 "Performance: %0 returns an existential, leading to heap allocation, reference counting, "
                 "and dynamic dispatch. Consider using generic constraints or concrete types instead.",
                 (const FuncDecl*))
-GROUPED_WARNING(perf_hint_closure_returns_existential,ExistentialType,DefaultIgnore,
+GROUPED_WARNING(perf_hint_closure_returns_existential,ExistentialType,none,
                 "Performance: closure returns an existential, leading to heap allocation, reference counting, "
                 "and dynamic dispatch. Consider using generic constraints or concrete types instead.", ())
-GROUPED_WARNING(perf_hint_var_uses_existential,ExistentialType,DefaultIgnore,
+GROUPED_WARNING(perf_hint_var_uses_existential,ExistentialType,none,
                 "Performance: %0 uses an existential, leading to heap allocation, reference counting, "
                 "and dynamic dispatch. Consider using generic constraints or concrete types instead.",
                 (const VarDecl *))
-GROUPED_WARNING(perf_hint_any_pattern_uses_existential,ExistentialType,DefaultIgnore,
+GROUPED_WARNING(perf_hint_any_pattern_uses_existential,ExistentialType,none,
                 "Performance: declaration uses an existential, leading to heap allocation, reference counting, "
                 "and dynamic dispatch. Consider using generic constraints or concrete types instead.",
                 ())
-GROUPED_WARNING(perf_hint_typealias_uses_existential,ExistentialType,DefaultIgnore,
+GROUPED_WARNING(perf_hint_typealias_uses_existential,ExistentialType,none,
                 "Performance: %0 aliases an existential type, leading to heap allocation, reference counting, "
                 "and dynamic dispatch. Consider using generic constraints or concrete types instead.",
                 (const TypeAliasDecl *))