Add API to AST nodes and session result objects to access the new ele…

…ment APIs

There will undoubtedly be other places where we need hooks, but I thought
that these would provide a good starting point for attempts to start
converting existing code to the new API.

Change-Id: If04aea4244efaca5a81553fbd88066b24c169290
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/385303
Reviewed-by: Konstantin Shcheglov <[email protected]>
Commit-Queue: Brian Wilkerson <[email protected]>

pkg/analyzer/lib/dart/analysis/results.dart

@@ -6,11 +6,13 @@ import 'package:analyzer/dart/analysis/analysis_options.dart';
 import 'package:analyzer/dart/analysis/session.dart';
 import 'package:analyzer/dart/ast/ast.dart';
 import 'package:analyzer/dart/element/element.dart';
+import 'package:analyzer/dart/element/element2.dart';
 import 'package:analyzer/dart/element/type_provider.dart';
 import 'package:analyzer/dart/element/type_system.dart';
 import 'package:analyzer/error/error.dart';
 import 'package:analyzer/file_system/file_system.dart';
 import 'package:analyzer/source/line_info.dart';
+import 'package:meta/meta.dart';
 
 /// The result of performing some kind of analysis on a single file. Every
 /// result that implements this interface will also implement a sub-interface.
@@ -59,6 +61,10 @@ abstract class ElementDeclarationResult {
   /// The [Element] that this object describes.
   Element get element;
 
+  /// The element that this object describes.
+  @experimental
+  Element2 get element2;
+
   /// The node that declares the [element]. Depending on whether it is returned
   /// from [ResolvedLibraryResult] or [ParsedLibraryResult] it might be resolved
   /// or just parsed.
@@ -152,6 +158,10 @@ abstract class InvalidResult {}
 abstract class LibraryElementResult implements SomeLibraryElementResult {
   /// The element of the library.
   LibraryElement get element;
+
+  /// The element representing the library.
+  @experimental
+  LibraryElement2 get element2;
 }
 
 /// The type of [InvalidResult] returned when the given element was not
@@ -204,6 +214,14 @@ abstract class ParsedLibraryResult
   /// is synthetic. Throw [ArgumentError] if the [element] is not defined in
   /// this library.
   ElementDeclarationResult? getElementDeclaration(Element element);
+
+  /// Returns the declaration of the [fragment].
+  ///
+  /// Returns `null` if the [fragment] is synthetic.
+  ///
+  /// Throws [ArgumentError] if the [fragment] is not defined in this library.
+  @experimental
+  ElementDeclarationResult? getElementDeclaration2(Fragment fragment);
 }
 
 /// The result of parsing of a single file. The errors returned include only
@@ -245,6 +263,10 @@ abstract class ResolvedLibraryResult
   /// The element representing this library.
   LibraryElement get element;
 
+  /// The element representing this library.
+  @experimental
+  LibraryElement2 get element2;
+
   /// The type provider used when resolving the library.
   TypeProvider get typeProvider;
 
@@ -269,6 +291,10 @@ abstract class ResolvedUnitResult
   /// The element representing the library containing the compilation [unit].
   LibraryElement get libraryElement;
 
+  /// The element representing the library containing the compilation [unit].
+  @experimental
+  LibraryElement2 get libraryElement2;
+
   /// The type provider used when resolving the compilation [unit].
   TypeProvider get typeProvider;
 
@@ -352,6 +378,10 @@ abstract class SomeUnitElementResult {}
 abstract class UnitElementResult implements SomeUnitElementResult, FileResult {
   /// The element of the file.
   CompilationUnitElement get element;
+
+  /// The fragment representing the content of the file.
+  @experimental
+  LibraryFragment get fragment;
 }
 
 /// The type of [InvalidResult] returned when something is wrong, but we

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

@@ -8,6 +8,7 @@ import 'package:analyzer/dart/ast/ast.dart';
 import 'package:analyzer/dart/ast/token.dart';
 import 'package:analyzer/dart/ast/visitor.dart';
 import 'package:analyzer/dart/element/element.dart';
+import 'package:analyzer/dart/element/element2.dart';
 import 'package:analyzer/dart/element/type_provider.dart';
 import 'package:analyzer/error/error.dart';
 import 'package:analyzer/file_system/file_system.dart';
@@ -162,6 +163,16 @@ class ElementDeclarationResultImpl implements ElementDeclarationResult {
 
   ElementDeclarationResultImpl(
       this.element, this.node, this.parsedUnit, this.resolvedUnit);
+
+  @override
+  Element2 get element2 {
+    if (element case Fragment fragment) {
+      return fragment.element;
+    } else if (element case Element2 element) {
+      return element;
+    }
+    throw UnimplementedError('Could not compute and element');
+  }
 }
 
 class ErrorsResultImpl implements ErrorsResult {
@@ -258,6 +269,9 @@ class LibraryElementResultImpl implements LibraryElementResult {
   final LibraryElement element;
 
   LibraryElementResultImpl(this.element);
+
+  @override
+  LibraryElement2 get element2 => element as LibraryElement2;
 }
 
 class ParsedLibraryResultImpl extends AnalysisResultImpl
@@ -299,6 +313,14 @@ class ParsedLibraryResultImpl extends AnalysisResultImpl
 
     return ElementDeclarationResultImpl(element, declaration, unitResult, null);
   }
+
+  @override
+  ElementDeclarationResult? getElementDeclaration2(Fragment fragment) {
+    if (fragment case Element element) {
+      return getElementDeclaration(element);
+    }
+    throw UnimplementedError();
+  }
 }
 
 class ParsedUnitResultImpl extends FileResultImpl implements ParsedUnitResult {
@@ -392,6 +414,9 @@ class ResolvedLibraryResultImpl extends AnalysisResultImpl
     required this.units,
   });
 
+  @override
+  LibraryElement2 get element2 => element as LibraryElement2;
+
   @override
   TypeProvider get typeProvider => element.typeProvider;
 
@@ -425,6 +450,14 @@ class ResolvedLibraryResultImpl extends AnalysisResultImpl
     return ElementDeclarationResultImpl(element, declaration, null, unitResult);
   }
 
+  @override
+  ElementDeclarationResult? getElementDeclaration2(Fragment fragment) {
+    if (fragment case Element element) {
+      return getElementDeclaration(element);
+    }
+    throw UnimplementedError();
+  }
+
   @override
   ResolvedUnitResult? unitWithPath(String path) {
     for (var unit in units) {
@@ -459,6 +492,9 @@ class ResolvedUnitResultImpl extends FileResultImpl
     return unit.declaredElement!.library;
   }
 
+  @override
+  LibraryElement2 get libraryElement2 => libraryElement as LibraryElement2;
+
   @override
   TypeProvider get typeProvider => libraryElement.typeProvider;
 
@@ -476,4 +512,7 @@ class UnitElementResultImpl extends FileResultImpl
     required super.fileState,
     required this.element,
   });
+
+  @override
+  LibraryFragment get fragment => element as LibraryFragment;
 }