Fine. Make ClassItem subtype lists nullable.

Class subtype metadata is now optional rather than always present. `ClassItem.allSubtypes` and `ClassItem.directSubtypesOfSealed` are changed to `ManifestItemIdList?` so we can distinguish “not recorded / not applicable” from “recorded but empty”. This reduces bundle size and prevents spurious requirement mismatches when these values weren’t requested. Key changes: - Switch `ClassItem.allSubtypes` and `directSubtypesOfSealed` to nullable; update binary read/write to use optional encodings. - Only populate `allSubtypes` when `ClassElementImpl.allSubtypes` is non-null; only populate `directSubtypesOfSealed` for sealed classes. - Extend requirement tracking with `allSubtypesRequested`/`directSubtypesOfSealedRequested` flags and compare values only when requested. Mismatch types now carry nullable expected/actual lists. - Update hash computation to include optional lists via `addOptionalIdList`. - Adjust printers to emit these fields only when meaningful; print `<null>` when a requested value is absent. - Bump `AnalysisDriver.DATA_VERSION` to 577 to reflect the format change. - Refresh tests and expected outputs to the new semantics. This clarifies intent (requested vs. empty), avoids false positives in requirements checking, and slightly shrinks stored manifests. Change-Id: I21ba890d63575e7bc5498d08e894580b662283f6 Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/455340 Reviewed-by: Johnni Winther <johnniwinther@google.com> Commit-Queue: Konstantin Shcheglov <scheglov@google.com>

Author: scheglov

pkg/analyzer/lib/src/dart/analysis/driver.dart

@@ -107,7 +107,7 @@ testFineAfterLibraryAnalyzerHook;
 // TODO(scheglov): Clean up the list of implicitly analyzed files.
 class AnalysisDriver {
  /// The version of data format, should be incremented on every format change.
- static const int DATA_VERSION = 575;
+ static const int DATA_VERSION = 577;
 
  /// The number of exception contexts allowed to write. Once this field is
  /// zero, we stop writing any new exception contexts in this process.

pkg/analyzer/lib/src/fine/library_manifest.dart

@@ -1016,6 +1016,15 @@ class LibraryManifestBuilder {
  builder.addList(idList.ids, addId);
  }
 
+ void addOptionalIdList(ManifestItemIdList? idList) {
+ if (idList != null) {
+ builder.addBool(true);
+ addIdList(idList);
+ } else {
+ builder.addBool(false);
+ }
+ }
+
  void addVersion(Version? version) {
  if (version != null) {
  builder.addBool(true);
@@ -1079,8 +1088,8 @@ class LibraryManifestBuilder {
  builder.addBool(item.hasNonFinalField);
  addId(item.interface.id);
  if (item is ClassItem) {
- addIdList(item.allSubtypes);
- addIdList(item.directSubtypesOfSealed);
+ addOptionalIdList(item.allSubtypes);
+ addOptionalIdList(item.directSubtypesOfSealed);
  }
  }
  }
@@ -1112,12 +1121,14 @@ class LibraryManifestBuilder {
  var classItem = declaredItems[classElement];
  if (classItem != null) {
  classItem as ClassItem;
- var ids = (classElement.allSubtypes ?? [])
- .map((type) => declaredItems[type.element])
- .whereType<InterfaceItem>()
- .map((item) => item.id)
- .sorted();
- classItem.allSubtypes = ManifestItemIdList(ids);
+ if (classElement.allSubtypes case var allSubtypes?) {
+ var ids = allSubtypes
+ .map((type) => declaredItems[type.element])
+ .whereType<InterfaceItem>()
+ .map((item) => item.id)
+ .sorted();
+ classItem.allSubtypes = ManifestItemIdList(ids);
+ }
  }
  }
  }

pkg/analyzer/lib/src/fine/manifest_item.dart

@@ -20,11 +20,11 @@ import 'package:pub_semver/pub_semver.dart';
 
 class ClassItem extends InterfaceItem<ClassElementImpl> {
  /// See [ClassElementImpl.allSubtypes] for details.
- ManifestItemIdList allSubtypes;
+ ManifestItemIdList? allSubtypes;
 
  /// See [ClassElementImpl.directSubtypesOfSealed] for details.
- /// If the class is not sealed, then empty.
- ManifestItemIdList directSubtypesOfSealed;
+ /// If the class is not sealed, then `null`.
+ ManifestItemIdList? directSubtypesOfSealed;
 
  ClassItem({
  required super.id,
@@ -70,8 +70,8 @@ class ClassItem extends InterfaceItem<ClassElementImpl> {
  mixins: element.mixins.encode(context),
  interfaces: element.interfaces.encode(context),
  interface: ManifestInterface.empty(),
- allSubtypes: ManifestItemIdList([]),
- directSubtypesOfSealed: ManifestItemIdList([]),
+ allSubtypes: null,
+ directSubtypesOfSealed: null,
  );
  });
  }
@@ -94,8 +94,8 @@ class ClassItem extends InterfaceItem<ClassElementImpl> {
  mixins: ManifestType.readList(reader),
  interfaces: ManifestType.readList(reader),
  interface: ManifestInterface.read(reader),
- allSubtypes: ManifestItemIdList.read(reader),
- directSubtypesOfSealed: ManifestItemIdList.read(reader),
+ allSubtypes: ManifestItemIdList.readOptional(reader),
+ directSubtypesOfSealed: ManifestItemIdList.readOptional(reader),
  );
  }
 
@@ -117,8 +117,8 @@ class ClassItem extends InterfaceItem<ClassElementImpl> {
  @override
  void write(BinaryWriter writer) {
  super.write(writer);
- allSubtypes.write(writer);
- directSubtypesOfSealed.write(writer);
+ allSubtypes.writeOptional(writer);
+ directSubtypesOfSealed.writeOptional(writer);
  }
 }
 

pkg/analyzer/lib/src/fine/requirement_failure.dart

@@ -188,8 +188,8 @@ class InterfaceChildrenIdsMismatch extends RequirementFailure {
  final Uri libraryUri;
  final LookupName interfaceName;
  final String childrenPropertyName;
- final ManifestItemIdList expectedIds;
- final ManifestItemIdList actualIds;
+ final ManifestItemIdList? expectedIds;
+ final ManifestItemIdList? actualIds;
 
  InterfaceChildrenIdsMismatch({
  required this.libraryUri,

pkg/analyzer/lib/src/fine/requirements.dart

@@ -318,10 +318,16 @@ class InterfaceItemRequirements {
  final Map<LookupName, ManifestItemId?> implementedMethods;
  final Map<int, Map<LookupName, ManifestItemId?>> superMethods;
 
- /// Set if [ClassElementImpl.allSubtypes] was invoked.
+ /// Whether [ClassElementImpl.allSubtypes] was requested.
+ bool allSubtypesRequested;
+
+ /// The recorded value of [ClassItem.allSubtypes].
  ManifestItemIdList? allSubtypes;
 
- /// Set if [ClassElementImpl.directSubtypesOfSealed] was invoked.
+ /// Whether [ClassElementImpl.directSubtypesOfSealed] was requested.
+ bool directSubtypesOfSealedRequested;
+
+ /// The recorded value of [ClassItem.directSubtypesOfSealed].
  ManifestItemIdList? directSubtypesOfSealed;
 
  InterfaceItemRequirements({
@@ -332,7 +338,9 @@ class InterfaceItemRequirements {
  required this.methods,
  required this.implementedMethods,
  required this.superMethods,
+ required this.allSubtypesRequested,
  required this.allSubtypes,
+ required this.directSubtypesOfSealedRequested,
  required this.directSubtypesOfSealed,
  });
 
@@ -345,7 +353,9 @@ class InterfaceItemRequirements {
  methods: {},
  implementedMethods: {},
  superMethods: {},
+ allSubtypesRequested: false,
  allSubtypes: null,
+ directSubtypesOfSealedRequested: false,
  directSubtypesOfSealed: null,
  );
  }
@@ -362,7 +372,9 @@ class InterfaceItemRequirements {
  readKey: () => reader.readInt64(),
  readValue: () => reader.readNameToOptionalIdMap(),
  ),
+ allSubtypesRequested: reader.readBool(),
  allSubtypes: ManifestItemIdList.readOptional(reader),
+ directSubtypesOfSealedRequested: reader.readBool(),
  directSubtypesOfSealed: ManifestItemIdList.readOptional(reader),
  );
  }
@@ -379,7 +391,9 @@ class InterfaceItemRequirements {
  writeKey: (index) => writer.writeInt64(index),
  writeValue: (map) => writer.writeNameToIdMap(map),
  );
+ writer.writeBool(allSubtypesRequested);
  allSubtypes.writeOptional(writer);
+ writer.writeBool(directSubtypesOfSealedRequested);
  directSubtypesOfSealed.writeOptional(writer);
  }
 }
@@ -1566,8 +1580,9 @@ class RequirementsManifest {
  }
  }
 
- if (interfaceRequirements.allSubtypes case var required?) {
+ if (interfaceRequirements.allSubtypesRequested) {
  interfaceItem as ClassItem;
+ var required = interfaceRequirements.allSubtypes;
  var actualIds = interfaceItem.allSubtypes;
  if (required != actualIds) {
  return InterfaceChildrenIdsMismatch(
@@ -1580,8 +1595,9 @@ class RequirementsManifest {
  }
  }
 
- if (interfaceRequirements.directSubtypesOfSealed case var required?) {
+ if (interfaceRequirements.directSubtypesOfSealedRequested) {
  interfaceItem as ClassItem;
+ var required = interfaceRequirements.directSubtypesOfSealed;
  var actualIds = interfaceItem.directSubtypesOfSealed;
  if (required != actualIds) {
  return InterfaceChildrenIdsMismatch(
@@ -1643,7 +1659,8 @@ class RequirementsManifest {
  var item = itemRequirements.item as ClassItem;
  var requirements = itemRequirements.requirements;
 
- requirements.allSubtypes ??= item.allSubtypes;
+ requirements.allSubtypesRequested = true;
+ requirements.allSubtypes = item.allSubtypes;
  }
 
  void record_classElement_directSubtypesOfSealed({
@@ -1661,7 +1678,8 @@ class RequirementsManifest {
  var item = itemRequirements.item as ClassItem;
  var requirements = itemRequirements.requirements;
 
- requirements.directSubtypesOfSealed ??= item.directSubtypesOfSealed;
+ requirements.directSubtypesOfSealedRequested = true;
+ requirements.directSubtypesOfSealed = item.directSubtypesOfSealed;
  }
 
  void record_fieldElement_getter({

pkg/analyzer/test/src/dart/analysis/driver_test.dart

@@ -6163,10 +6163,10 @@ void f(A a) {
  B: false
  interfaces
  A
- allSubtypes: []
+ allSubtypes: <null>
  directSubtypesOfSealed: #M2
  B
- allSubtypes: []
+ allSubtypes: <null>
 [status] idle
 [future] getErrors T1
  ErrorsResult #0
@@ -6227,10 +6227,10 @@ class C extends A {}
  B: false
  interfaces
  A
- allSubtypes: []
+ allSubtypes: <null>
  directSubtypesOfSealed: #M2 #M8
  B
- allSubtypes: []
+ allSubtypes: <null>
 [status] idle
 [future] getErrors T2
  ErrorsResult #1
@@ -56054,6 +56054,7 @@ class extends A {}
  A: #M0
  flags: isFinal
  supertype: Object @ dart:core
+ allSubtypes: []
  interface: #M1
  exportMapId: #M2
  exportMap
@@ -56216,6 +56217,7 @@ class C {}
  B: #M1
  flags: isFinal
  supertype: A @ package:test/test.dart
+ allSubtypes: []
  interface: #M3
  C: #M4
  supertype: Object @ dart:core
@@ -56254,6 +56256,7 @@ final class D extends B {}
  D: #M7
  flags: isFinal
  supertype: B @ package:test/test.dart
+ allSubtypes: []
  interface: #M8
  exportMapId: #M9
  exportMap
@@ -68326,6 +68329,7 @@ class D {}
  }
 
  test_manifest_class_modifier_isFinal() async {
+ configuration.withElementManifests = true;
  await _runLibraryManifestScenario(
  initialCode: r'''
 class A {}
@@ -68340,12 +68344,20 @@ final class D {}
  hashForRequirements: #H0
  declaredClasses
  A: #M0
+ supertype: Object @ dart:core
  interface: #M1
  B: #M2
+ flags: isFinal
+ supertype: Object @ dart:core
+ allSubtypes: []
  interface: #M3
  C: #M4
+ supertype: Object @ dart:core
  interface: #M5
  D: #M6
+ flags: isFinal
+ supertype: Object @ dart:core
+ allSubtypes: []
  interface: #M7
  exportMapId: #M8
  exportMap
@@ -68366,12 +68378,20 @@ class D {}
  hashForRequirements: #H1
  declaredClasses
  A: #M0
+ supertype: Object @ dart:core
  interface: #M1
  B: #M2
+ flags: isFinal
+ supertype: Object @ dart:core
+ allSubtypes: []
  interface: #M3
  C: #M9
+ flags: isFinal
+ supertype: Object @ dart:core
+ allSubtypes: []
  interface: #M10
  D: #M11
+ supertype: Object @ dart:core
  interface: #M12
  exportMapId: #M13
  exportMap
@@ -68568,6 +68588,7 @@ class D {}
  }
 
  test_manifest_class_modifier_isSealed() async {
+ configuration.withElementManifests = true;
  await _runLibraryManifestScenario(
  initialCode: r'''
 class A {}
@@ -68582,12 +68603,22 @@ sealed class D {}
  hashForRequirements: #H0
  declaredClasses
  A: #M0
+ supertype: Object @ dart:core
  interface: #M1
  B: #M2
+ flags: isAbstract isSealed
+ supertype: Object @ dart:core
+ allSubtypes: []
+ directSubtypesOfSealed: []
  interface: #M3
  C: #M4
+ supertype: Object @ dart:core
  interface: #M5
  D: #M6
+ flags: isAbstract isSealed
+ supertype: Object @ dart:core
+ allSubtypes: []
+ directSubtypesOfSealed: []
  interface: #M7
  exportMapId: #M8
  exportMap
@@ -68608,12 +68639,22 @@ class D {}
  hashForRequirements: #H1
  declaredClasses
  A: #M0
+ supertype: Object @ dart:core
  interface: #M1
  B: #M2
+ flags: isAbstract isSealed
+ supertype: Object @ dart:core
+ allSubtypes: []
+ directSubtypesOfSealed: []
  interface: #M3
  C: #M9
+ flags: isAbstract isSealed
+ supertype: Object @ dart:core
+ allSubtypes: []
+ directSubtypesOfSealed: []
  interface: #M10
  D: #M11
+ supertype: Object @ dart:core
  interface: #M12
  exportMapId: #M13
  exportMap