Elements. Move aliasedType into TypeAliasElementImpl.

Change-Id: Ic4882ff7cf0960b09b68f6a062acacd0e9e7c061
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/440062
Reviewed-by: Samuel Rawlins <[email protected]>
Commit-Queue: Konstantin Shcheglov <[email protected]>

Author: scheglov

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

@@ -109,7 +109,7 @@ 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 = 504;
+  static const int DATA_VERSION = 505;
 
   /// 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/dart/element/display_string_builder.dart

@@ -371,7 +371,7 @@ class ElementDisplayStringBuilder {
     if (aliasedElement != null) {
       aliasedElement.appendTo(this);
     } else {
-      _writeType(element.aliasedType);
+      _writeType(element.element.aliasedType);
     }
   }
 

pkg/analyzer/lib/src/dart/element/element.dart

@@ -9648,6 +9648,8 @@ class TypeAliasElementImpl extends TypeDefiningElementImpl
   @override
   final TypeAliasFragmentImpl firstFragment;
 
+  TypeImpl? _aliasedType;
+
   TypeAliasElementImpl(this.reference, this.firstFragment) {
     reference.element = this;
     firstFragment.element = this;
@@ -9671,14 +9673,19 @@ class TypeAliasElementImpl extends TypeDefiningElementImpl
   }
 
   @override
-  TypeImpl get aliasedType => firstFragment.aliasedType;
+  TypeImpl get aliasedType {
+    _ensureReadResolution();
+    return _aliasedType!;
+  }
 
-  set aliasedType(TypeImpl value) {
-    firstFragment.aliasedType = value;
+  set aliasedType(DartType rawType) {
+    // TODO(paulberry): eliminate this cast by changing the type of the
+    // `rawType` parameter.
+    _aliasedType = rawType as TypeImpl;
   }
 
   /// The aliased type, might be `null` if not yet linked.
-  TypeImpl? get aliasedTypeRaw => firstFragment.aliasedTypeRaw;
+  TypeImpl? get aliasedTypeRaw => _aliasedType;
 
   @override
   TypeAliasElementImpl get baseElement => this;
@@ -9889,7 +9896,6 @@ class TypeAliasFragmentImpl extends _ExistingFragmentImpl
   bool isFunctionTypeAliasBased = false;
 
   FragmentImpl? _aliasedElement;
-  TypeImpl? _aliasedType;
 
   @override
   late TypeAliasElementImpl element;
@@ -9914,25 +9920,6 @@ class TypeAliasFragmentImpl extends _ExistingFragmentImpl
     return _aliasedElement;
   }
 
-  /// The aliased type.
-  ///
-  /// If non-function type aliases feature is enabled for the enclosing library,
-  /// this type might be just anything. If the feature is disabled, return
-  /// a [FunctionType].
-  TypeImpl get aliasedType {
-    _ensureReadResolution();
-    return _aliasedType!;
-  }
-
-  set aliasedType(DartType rawType) {
-    // TODO(paulberry): eliminate this cast by changing the type of the
-    // `rawType` parameter.
-    _aliasedType = rawType as TypeImpl;
-  }
-
-  /// The aliased type, might be `null` if not yet linked.
-  TypeImpl? get aliasedTypeRaw => _aliasedType;
-
   @override
   List<Fragment> get children => const [];
 

pkg/analyzer/lib/src/summary2/bundle_reader.dart

@@ -1301,8 +1301,16 @@ class LibraryReader {
     _libraryElement.typeAliases = _reader.readTypedList(() {
       var reference = _readReference();
       var fragments = _readFragmentsById<TypeAliasFragmentImpl>();
-      // TODO(scheglov): link fragments.
       var element = TypeAliasElementImpl(reference, fragments.first);
+
+      element.deferReadResolution(
+        _createDeferredReadResolutionCallback((reader) {
+          // TODO(scheglov): remove cast
+          reader._addTypeParameters2(element.typeParameters.cast());
+          element.aliasedType = reader.readRequiredType();
+        }),
+      );
+
       return element;
     });
   }
@@ -1331,7 +1339,6 @@ class LibraryReader {
           );
           _readFragmentMetadata(fragment, reader);
           fragment.aliasedElement = reader._readAliasedElement(unitElement);
-          fragment.aliasedType = reader.readRequiredType();
         },
       );
     });

pkg/analyzer/lib/src/summary2/bundle_writer.dart

@@ -744,7 +744,12 @@ class BundleWriter {
     _sink.writeList(elements, (element) {
       _writeReference(element.reference);
       _sink.writeList(element.fragments, _writeFragmentId);
-      // TODO(scheglov): resolution too?
+
+      _writeElementResolution(() {
+        _resolutionSink.withTypeParameters(element.typeParameters.cast(), () {
+          _resolutionSink.writeType(element.aliasedType);
+        });
+      });
     });
   }
 
@@ -754,7 +759,6 @@ class BundleWriter {
       _writeTypeParameters(fragment.typeParameters, () {
         _resolutionSink._writeMetadata(fragment.metadata);
         _resolutionSink._writeAliasedElement(fragment.aliasedElement);
-        _resolutionSink.writeType(fragment.aliasedType);
       });
     });
   }

pkg/analyzer/lib/src/summary2/types_builder.dart

@@ -343,7 +343,7 @@ class TypesBuilder {
     var fragment = node.declaredFragment!;
     var function = fragment.aliasedElement as GenericFunctionTypeFragmentImpl;
     function.returnType = node.returnType?.type ?? _dynamicType;
-    fragment.aliasedType = function.type;
+    fragment.element.aliasedType = function.type;
   }
 
   void _functionTypedFormalParameter(FunctionTypedFormalParameterImpl node) {
@@ -364,15 +364,16 @@ class TypesBuilder {
 
   void _genericTypeAlias(GenericTypeAliasImpl node) {
     var fragment = node.declaredFragment!;
-    var featureSet = fragment.library.featureSet;
+    var element = fragment.element;
+    var featureSet = element.library.featureSet;
 
     var typeNode = node.type;
     if (featureSet.isEnabled(Feature.nonfunction_type_aliases)) {
-      fragment.aliasedType = typeNode.typeOrThrow;
+      element.aliasedType = typeNode.typeOrThrow;
     } else if (typeNode is GenericFunctionType) {
-      fragment.aliasedType = typeNode.typeOrThrow;
+      element.aliasedType = typeNode.typeOrThrow;
     } else {
-      fragment.aliasedType = _errorFunctionType();
+      element.aliasedType = _errorFunctionType();
     }
   }
 

pkg/analyzer/test/generated/elements_types_mixin.dart

@@ -659,9 +659,10 @@ mixin ElementsTypesMixin {
     var fragment = TypeAliasFragmentImpl(name: name, firstTokenOffset: null);
     fragment.enclosingElement = testLibrary.definingCompilationUnit;
     fragment.typeParameters = typeParameters.map((e) => e.asElement).toList();
-    fragment.aliasedType = aliasedType;
 
-    return TypeAliasElementImpl(Reference.root(), fragment);
+    var element = TypeAliasElementImpl(Reference.root(), fragment);
+    element.aliasedType = aliasedType;
+    return element;
   }
 
   TypeImpl typeAliasTypeNone(