[analysis_server] Migrate LSP Go-To handlers to new element model

Change-Id: Ie517dcbba87c34d12a42707c3beea141d3fd509a
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/393880
Reviewed-by: Konstantin Shcheglov <[email protected]>
Reviewed-by: Brian Wilkerson <[email protected]>
Commit-Queue: Brian Wilkerson <[email protected]>

Author: DanTup

pkg/analysis_server/analyzer_use_new_elements.txt

@@ -23,9 +23,6 @@ lib/src/lsp/handlers/code_actions/dart.dart
 lib/src/lsp/handlers/commands/abstract_refactor.dart
 lib/src/lsp/handlers/custom/abstract_go_to.dart
 lib/src/lsp/handlers/custom/handler_imports.dart
-lib/src/lsp/handlers/custom/handler_augmentation.dart
-lib/src/lsp/handlers/custom/handler_augmented.dart
-lib/src/lsp/handlers/custom/handler_super.dart
 lib/src/lsp/handlers/handler_completion.dart
 lib/src/lsp/handlers/handler_completion_resolve.dart
 lib/src/lsp/handlers/handler_definition.dart

pkg/analysis_server/lib/src/lsp/handlers/custom/abstract_go_to.dart

@@ -18,11 +18,10 @@ import 'package:meta/meta.dart';
 /// a location to navigate to a particular kind of related element, such as
 /// Super, Augmentation Target or Augmentation.
 abstract class AbstractGoToHandler
-    extends
-        SharedMessageHandler<
-          TextDocumentPositionParams,
-          Either2<Location, List<Location>>?
-        > {
+        // TODO(dantup): Remove this class after https://dart-review.googlesource.com/c/sdk/+/393861
+        //  lands.
+        extends
+        SharedMessageHandler<TextDocumentPositionParams, Either2<Location, List<Location>>?> {
   AbstractGoToHandler(super.server);
 
   @override

pkg/analysis_server/lib/src/lsp/handlers/custom/handler_augmentation.dart

@@ -4,30 +4,54 @@
 
 import 'package:analysis_server/lsp_protocol/protocol.dart' hide Element;
 import 'package:analysis_server/src/lsp/constants.dart';
-import 'package:analysis_server/src/lsp/handlers/custom/abstract_go_to.dart';
-import 'package:analyzer/dart/analysis/results.dart';
-import 'package:analyzer/dart/element/element.dart';
-import 'package:analyzer/src/utilities/extensions/element.dart';
+import 'package:analysis_server/src/lsp/error_or.dart';
+import 'package:analysis_server/src/lsp/handlers/handlers.dart';
+import 'package:analysis_server/src/lsp/mapping.dart';
+import 'package:analyzer/src/dart/ast/ast.dart';
+import 'package:analyzer/src/utilities/extensions/ast.dart';
 
-class AugmentationHandler extends AbstractGoToHandler {
+class AugmentationHandler
+    extends SharedMessageHandler<TextDocumentPositionParams, Location?> {
   AugmentationHandler(super.server);
 
   @override
   Method get handlesMessage => CustomMethods.augmentation;
 
+  @override
+  LspJsonHandler<TextDocumentPositionParams> get jsonHandler =>
+      TextDocumentPositionParams.jsonHandler;
+
   @override
   bool get requiresTrustedCaller => false;
 
   @override
-  Either2<Location?, List<Location>> findRelatedLocations(
-      Element element,
-      ResolvedLibraryResult libraryResult,
-      ResolvedUnitResult unit,
-      String? prefix) {
-    // Although the base class supports returning multiple elements, this
-    // handler is documented to only return a single element.
-    // Changing this to return a list could be a breaking change for
-    // clients.
-    return Either2.t1(elementToLocation(element.augmentation));
+  Future<ErrorOr<Location?>> handle(
+    TextDocumentPositionParams params,
+    MessageInfo message,
+    CancellationToken token,
+  ) async {
+    if (!isDartDocument(params.textDocument)) {
+      return success(null);
+    }
+
+    var pos = params.position;
+    var path = pathOfDoc(params.textDocument);
+    var unit = await path.mapResult(requireResolvedUnit);
+    var offset = unit.mapResultSync((unit) => toOffset(unit.lineInfo, pos));
+
+    return (unit, offset).mapResultsSync((unit, offset) {
+      // Find the nearest node that could have fragments.
+      var node =
+          unit.unit
+              .nodeCovering(offset: offset)
+              ?.thisOrAncestorOfType<FragmentDeclaration>();
+
+      var location = fragmentToLocation(
+        uriConverter,
+        // Augmentation = next fragment.
+        node?.declaredFragment?.nextFragment,
+      );
+      return success(location);
+    });
   }
 }

pkg/analysis_server/lib/src/lsp/handlers/custom/handler_augmented.dart

@@ -4,34 +4,54 @@
 
 import 'package:analysis_server/lsp_protocol/protocol.dart' hide Element;
 import 'package:analysis_server/src/lsp/constants.dart';
-import 'package:analysis_server/src/lsp/handlers/custom/abstract_go_to.dart';
-import 'package:analyzer/dart/analysis/results.dart';
-import 'package:analyzer/dart/element/element.dart';
+import 'package:analysis_server/src/lsp/error_or.dart';
+import 'package:analysis_server/src/lsp/handlers/handlers.dart';
+import 'package:analysis_server/src/lsp/mapping.dart';
+import 'package:analyzer/src/dart/ast/ast.dart';
+import 'package:analyzer/src/utilities/extensions/ast.dart';
 
-class AugmentedHandler extends AbstractGoToHandler {
+class AugmentedHandler
+    extends SharedMessageHandler<TextDocumentPositionParams, Location?> {
   AugmentedHandler(super.server);
 
   @override
   Method get handlesMessage => CustomMethods.augmented;
 
+  @override
+  LspJsonHandler<TextDocumentPositionParams> get jsonHandler =>
+      TextDocumentPositionParams.jsonHandler;
+
   @override
   bool get requiresTrustedCaller => false;
 
   @override
-  Either2<Location?, List<Location>> findRelatedLocations(
-      Element element,
-      ResolvedLibraryResult libraryResult,
-      ResolvedUnitResult unit,
-      String? prefix) {
-    // Although the base class supports returning multiple elements, this
-    // handler is documented to only return a single element.
-    // Changing this to return a list could be a breaking change for
-    // clients.
-    return Either2.t1(elementToLocation(switch (element) {
-      ExecutableElement element => element.augmentationTarget,
-      InstanceElement element => element.augmentationTarget,
-      PropertyInducingElement element => element.augmentationTarget,
-      _ => null,
-    }));
+  Future<ErrorOr<Location?>> handle(
+    TextDocumentPositionParams params,
+    MessageInfo message,
+    CancellationToken token,
+  ) async {
+    if (!isDartDocument(params.textDocument)) {
+      return success(null);
+    }
+
+    var pos = params.position;
+    var path = pathOfDoc(params.textDocument);
+    var unit = await path.mapResult(requireResolvedUnit);
+    var offset = unit.mapResultSync((unit) => toOffset(unit.lineInfo, pos));
+
+    return (unit, offset).mapResultsSync((unit, offset) {
+      // Find the nearest node that could have fragments.
+      var node =
+          unit.unit
+              .nodeCovering(offset: offset)
+              ?.thisOrAncestorOfType<FragmentDeclaration>();
+
+      var location = fragmentToLocation(
+        uriConverter,
+        // Augmented = previous fragment.
+        node?.declaredFragment?.previousFragment,
+      );
+      return success(location);
+    });
   }
 }

pkg/analysis_server/lib/src/lsp/handlers/custom/handler_super.dart

@@ -4,71 +4,119 @@
 
 import 'package:analysis_server/lsp_protocol/protocol.dart' hide Element;
 import 'package:analysis_server/src/lsp/constants.dart';
-import 'package:analysis_server/src/lsp/handlers/custom/abstract_go_to.dart';
-import 'package:analyzer/dart/analysis/results.dart';
-import 'package:analyzer/dart/element/element.dart';
+import 'package:analysis_server/src/lsp/error_or.dart';
+import 'package:analysis_server/src/lsp/handlers/handlers.dart';
+import 'package:analysis_server/src/lsp/mapping.dart';
+import 'package:analyzer/dart/ast/ast.dart';
+import 'package:analyzer/dart/element/element2.dart';
 import 'package:analyzer/src/dart/analysis/session.dart';
+import 'package:analyzer/src/dart/ast/element_locator.dart';
 import 'package:analyzer/src/dart/element/inheritance_manager3.dart';
-import 'package:analyzer/src/utilities/extensions/element.dart';
+import 'package:analyzer/src/utilities/extensions/ast.dart';
 
-class SuperHandler extends AbstractGoToHandler {
+class SuperHandler
+    extends SharedMessageHandler<TextDocumentPositionParams, Location?> {
   SuperHandler(super.server);
 
   @override
   Method get handlesMessage => CustomMethods.super_;
 
+  @override
+  LspJsonHandler<TextDocumentPositionParams> get jsonHandler =>
+      TextDocumentPositionParams.jsonHandler;
+
   @override
   bool get requiresTrustedCaller => false;
 
   @override
-  Either2<Location?, List<Location>> findRelatedLocations(
-      Element element,
-      ResolvedLibraryResult libraryResult,
-      ResolvedUnitResult unit,
-      String? prefix) {
-    // Although the base class supports returning multiple elements, this
-    // handler is documented to only return a single element.
-    // Changing this to return a list could be a breaking change for
-    // clients.
-    return Either2.t1(
-        elementToLocation(_SuperComputer().computeSuper(element)));
+  Future<ErrorOr<Location?>> handle(
+    TextDocumentPositionParams params,
+    MessageInfo message,
+    CancellationToken token,
+  ) async {
+    if (!isDartDocument(params.textDocument)) {
+      return success(null);
+    }
+
+    var pos = params.position;
+    var path = pathOfDoc(params.textDocument);
+    var unit = await path.mapResult(requireResolvedUnit);
+    var offset = unit.mapResultSync((unit) => toOffset(unit.lineInfo, pos));
+
+    return (unit, offset).mapResultsSync((unit, offset) {
+      // Find the nearest node that could have a super.
+      var node = unit.unit
+          .nodeCovering(offset: offset)
+          ?.thisOrAncestorMatching(_canHaveSuper);
+      if (node == null) {
+        return success(null);
+      }
+
+      var element = ElementLocator.locate2(node);
+      if (element == null) {
+        return success(null);
+      }
+
+      var targetFragment = _SuperComputer().computeSuper(element);
+      var location = fragmentToLocation(uriConverter, targetFragment);
+      return success(location);
+    });
   }
+
+  /// Returns whether [node] is something that can be considered to have a
+  /// "super" (a class or a class member).
+  bool _canHaveSuper(AstNode node) =>
+      node is ClassDeclaration || node is ClassMember;
 }
 
 class _SuperComputer {
-  Element? computeSuper(Element element) {
+  Fragment? computeSuper(Element2 element) {
     return switch (element) {
-      ConstructorElement element => _findSuperConstructor(element),
-      InterfaceElement element => _findSuperClass(element),
+      ConstructorElement2 element => _findSuperConstructor(element),
+      InterfaceElement2 element => _findSuperClass(element),
       _ => _findSuperMember(element),
     };
   }
 
-  Element? _findSuperClass(InterfaceElement element) {
-    return element.supertype?.element;
+  Fragment? _findSuperClass(InterfaceElement2 element) {
+    // For super classes, we use the first fragment (the original declaration).
+    // This differs from methods/getters because we jump to the end of the
+    // augmentation chain for those.
+    return element.supertype?.element3.firstFragment;
   }
 
-  Element? _findSuperConstructor(ConstructorElement element) {
-    return element.superConstructor?.withAugmentations.last;
+  Fragment? _findSuperConstructor(ConstructorElement2 element) {
+    return _lastFragment(element.superConstructor2);
   }
 
-  Element? _findSuperMember(Element element) {
+  Fragment? _findSuperMember(Element2 element) {
     var session = element.session;
     if (session is! AnalysisSessionImpl) {
       return null;
     }
 
     var inheritanceManager = session.inheritanceManager;
-    var elementName = element.name;
-    var interfaceElement = element.thisOrAncestorOfType<InterfaceElement>();
+    var elementName = element.name3;
+    var interfaceElement = element.thisOrAncestorOfType2<InterfaceElement2>();
 
     if (elementName == null || interfaceElement == null) {
       return null;
     }
 
-    var name = Name(interfaceElement.library.source.uri, elementName);
-    var member = inheritanceManager.getInherited2(interfaceElement, name);
+    var name = Name(
+      interfaceElement.library2.firstFragment.source.uri,
+      elementName,
+    );
+    var member = inheritanceManager.getInherited4(interfaceElement, name);
 
-    return member;
+    return _lastFragment(member);
+  }
+
+  Fragment? _lastFragment(FragmentedElement? element) {
+    Fragment? fragment = element?.firstFragment;
+    while (fragment?.nextFragment != null) {
+      fragment = fragment?.nextFragment;
+    }
+    return fragment;
   }
 }

pkg/analysis_server/lib/src/lsp/mapping.dart

@@ -23,6 +23,7 @@ import 'package:analysis_server/src/services/completion/dart/feature_computer.da
 import 'package:analysis_server/src/services/snippets/snippet.dart';
 import 'package:analysis_server/src/utilities/extensions/string.dart';
 import 'package:analyzer/dart/analysis/results.dart' as server;
+import 'package:analyzer/dart/element/element2.dart';
 import 'package:analyzer/error/error.dart' as server;
 import 'package:analyzer/source/line_info.dart' as server;
 import 'package:analyzer/source/line_info.dart';
@@ -497,6 +498,41 @@ lsp.SymbolKind elementKindToSymbolKind(
   );
 }
 
+lsp.Location? fragmentToLocation(
+  ClientUriConverter uriConverter,
+  Fragment? fragment,
+) {
+  if (fragment == null) {
+    return null;
+  }
+
+  var libraryFragment = fragment.libraryFragment;
+  var sourcePath = libraryFragment.source.fullName;
+
+  var nameOffset = fragment.nameOffset2;
+  var nameLength = fragment.name2?.length;
+
+  // For unnamed constructors, use the type name as the target location.
+  if (nameOffset == null && fragment is ConstructorFragment) {
+    nameOffset = fragment.typeNameOffset;
+    nameLength = fragment.typeName?.length;
+  }
+
+  if (nameOffset == null || nameLength == null) {
+    // This is some kind of synthetic fragment we can't navigate to.
+    return null;
+  }
+
+  return lsp.Location(
+    uri: uriConverter.toClientUri(sourcePath),
+    range: toRange(
+      libraryFragment.lineInfo,
+      nameOffset,
+      nameLength,
+    ),
+  );
+}
+
 /// Returns additional details to be shown against a completion.
 CompletionDetail getCompletionDetail(
   server.CompletionSuggestion suggestion, {