| // Copyright (c) 2018, the Dart project authors. Please see the AUTHORS file |
| // for details. All rights reserved. Use of this source code is governed by a |
| // BSD-style license that can be found in the LICENSE file. |
| |
| import 'package:analysis_server/src/computer/computer_hover.dart'; |
| import 'package:analysis_server/src/protocol_server.dart'; |
| import 'package:analysis_server/src/utilities/extensions/ast.dart'; |
| import 'package:analyzer/dart/ast/ast.dart'; |
| import 'package:analyzer/dart/element/element.dart'; |
| import 'package:analyzer/src/dart/ast/element_locator.dart'; |
| import 'package:analyzer/src/dart/ast/utilities.dart'; |
| import 'package:analyzer/src/dartdoc/dartdoc_directive_info.dart'; |
| |
| /// A computer for the signature at the specified offset of a Dart |
| /// [CompilationUnit]. |
| class DartUnitSignatureComputer { |
| final DartdocDirectiveInfo _dartdocInfo; |
| final AstNode? _node; |
| late ArgumentList _argumentList; |
| final bool _isNonNullableByDefault; |
| DartUnitSignatureComputer(this._dartdocInfo, CompilationUnit unit, int offset) |
| : _node = NodeLocator(offset).searchWithin(unit), |
| _isNonNullableByDefault = unit.isNonNullableByDefault; |
| |
| /// The [ArgumentList] node located by [compute]. |
| ArgumentList get argumentList => _argumentList; |
| |
| bool get offsetIsValid => _node != null; |
| |
| /// Returns the computed signature information, maybe `null`. |
| AnalysisGetSignatureResult? compute() { |
| var argumentList = _findArgumentList(); |
| if (argumentList == null) { |
| return null; |
| } |
| String? name; |
| ExecutableElement? execElement; |
| final parent = argumentList.parent; |
| if (parent is MethodInvocation) { |
| name = parent.methodName.name; |
| var element = ElementLocator.locate(parent); |
| execElement = element is ExecutableElement ? element : null; |
| } else if (parent is InstanceCreationExpression) { |
| name = parent.constructorName.type.name.name; |
| var constructorName = parent.constructorName.name; |
| if (constructorName != null) { |
| name += '.${constructorName.name}'; |
| } |
| execElement = ElementLocator.locate(parent) as ExecutableElement?; |
| } |
| |
| if (name == null || execElement == null) { |
| return null; |
| } |
| |
| _argumentList = argumentList; |
| |
| final parameters = |
| execElement.parameters.map((p) => _convertParam(p)).toList(); |
| |
| return AnalysisGetSignatureResult(name, parameters, |
| dartdoc: DartUnitHoverComputer.computeDocumentation( |
| _dartdocInfo, execElement) |
| ?.full); |
| } |
| |
| ParameterInfo _convertParam(ParameterElement param) { |
| return ParameterInfo( |
| param.isOptionalNamed |
| ? ParameterKind.OPTIONAL_NAMED |
| : param.isOptionalPositional |
| ? ParameterKind.OPTIONAL_POSITIONAL |
| : param.isRequiredNamed |
| ? ParameterKind.REQUIRED_NAMED |
| : ParameterKind.REQUIRED_POSITIONAL, |
| param.displayName, |
| param.type.getDisplayString(withNullability: _isNonNullableByDefault), |
| defaultValue: param.defaultValueCode); |
| } |
| |
| /// Return the closest argument list surrounding the [_node]. |
| ArgumentList? _findArgumentList() { |
| var node = _node; |
| while (node != null && node is! ArgumentList) { |
| // Certain nodes don't make sense to search above for an argument list |
| // (for example when inside a function expression). |
| if (node is FunctionExpression) { |
| return null; |
| } |
| node = node.parent; |
| } |
| return node as ArgumentList?; |
| } |
| } |