pkg/analysis_server/lib/src/services/completion/dart/suggestion_builder.dart - sdk.git - Git at Google

 // Copyright (c) 2015, 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 'dart:collection';

 import 'package:analysis_server/src/protocol_server.dart' as protocol;
 import 'package:analysis_server/src/protocol_server.dart'
     hide Element, ElementKind;
 import 'package:analysis_server/src/provisional/completion/dart/completion_dart.dart';
 import 'package:analysis_server/src/services/completion/dart/utilities.dart';
 import 'package:analyzer/dart/element/element.dart';
 import 'package:analyzer/dart/element/type.dart';
 import 'package:analyzer/dart/element/visitor.dart';
 import 'package:analyzer/src/util/comment.dart';

 import '../../../protocol_server.dart' show CompletionSuggestion;

 /**
  * Return a suggestion based upon the given element or `null` if a suggestion
  * is not appropriate for the given element.
  */
 CompletionSuggestion createSuggestion(Element element,
     {String completion,
     CompletionSuggestionKind kind = CompletionSuggestionKind.INVOCATION,
     int relevance = DART_RELEVANCE_DEFAULT}) {
   if (element == null) {
     return null;
   }
   if (element is ExecutableElement && element.isOperator) {
     // Do not include operators in suggestions
     return null;
   }
   if (completion == null) {
     completion = element.displayName;
   }
   bool isDeprecated = element.hasDeprecated;
   CompletionSuggestion suggestion = new CompletionSuggestion(
       kind,
       isDeprecated ? DART_RELEVANCE_LOW : relevance,
       completion,
       completion.length,
       0,
       isDeprecated,
       false);

   // Attach docs.
   String doc = getDartDocPlainText(element.documentationComment);
   suggestion.docComplete = doc;
   suggestion.docSummary = getDartDocSummary(doc);

   suggestion.element = protocol.convertElement(element);
   Element enclosingElement = element.enclosingElement;
   if (enclosingElement is ClassElement) {
     suggestion.declaringType = enclosingElement.displayName;
   }
   suggestion.returnType = getReturnTypeString(element);
   if (element is ExecutableElement && element is! PropertyAccessorElement) {
     suggestion.parameterNames = element.parameters
         .map((ParameterElement parameter) => parameter.name)
         .toList();
     suggestion.parameterTypes =
         element.parameters.map((ParameterElement parameter) {
       DartType paramType = parameter.type;
       // Gracefully degrade if type not resolved yet
       return paramType != null ? paramType.displayName : 'var';
     }).toList();

     Iterable<ParameterElement> requiredParameters = element.parameters
         .where((ParameterElement param) => param.isRequiredPositional);
     suggestion.requiredParameterCount = requiredParameters.length;

     Iterable<ParameterElement> namedParameters =
         element.parameters.where((ParameterElement param) => param.isNamed);
     suggestion.hasNamedParameters = namedParameters.isNotEmpty;

     addDefaultArgDetails(
         suggestion, element, requiredParameters, namedParameters);
   }
   return suggestion;
 }

 /**
  * Common mixin for sharing behavior.
  */
 mixin ElementSuggestionBuilder {
   /**
    * A collection of completion suggestions.
    */
   final List<CompletionSuggestion> suggestions = <CompletionSuggestion>[];

   /**
    * A set of existing completions used to prevent duplicate suggestions.
    */
   final Set<String> _completions = new Set<String>();

   /**
    * A map of element names to suggestions for synthetic getters and setters.
    */
   final Map<String, CompletionSuggestion> _syntheticMap =
       <String, CompletionSuggestion>{};

   /**
    * Return the library in which the completion is requested.
    */
   LibraryElement get containingLibrary;

   /**
    * Return the kind of suggestions that should be built.
    */
   CompletionSuggestionKind get kind;

   /**
    * Add a suggestion based upon the given element.
    */
   CompletionSuggestion addSuggestion(Element element,
       {String prefix,
       int relevance = DART_RELEVANCE_DEFAULT,
       String elementCompletion}) {
     if (element.isPrivate) {
       if (element.library != containingLibrary) {
         return null;
       }
     }
     String completion = elementCompletion ?? element.displayName;
     if (prefix != null && prefix.isNotEmpty) {
       if (completion == null || completion.isEmpty) {
         completion = prefix;
       } else {
         completion = '$prefix.$completion';
       }
     }
     if (completion == null || completion.isEmpty) {
       return null;
     }
     CompletionSuggestion suggestion = createSuggestion(element,
         completion: completion, kind: kind, relevance: relevance);
     if (suggestion != null) {
       if (element.isSynthetic && element is PropertyAccessorElement) {
         String cacheKey;
         if (element.isGetter) {
           cacheKey = element.name;
         }
         if (element.isSetter) {
           cacheKey = element.name;
           cacheKey = cacheKey.substring(0, cacheKey.length - 1);
         }
         if (cacheKey != null) {
           CompletionSuggestion existingSuggestion = _syntheticMap[cacheKey];

           // Pair getter/setter by updating the existing suggestion
           if (existingSuggestion != null) {
             CompletionSuggestion getter =
                 element.isGetter ? suggestion : existingSuggestion;
             protocol.ElementKind elemKind =
                 element.enclosingElement is ClassElement
                     ? protocol.ElementKind.FIELD
                     : protocol.ElementKind.TOP_LEVEL_VARIABLE;
             existingSuggestion.element = new protocol.Element(
                 elemKind,
                 existingSuggestion.element.name,
                 existingSuggestion.element.flags,
                 location: getter.element.location,
                 typeParameters: getter.element.typeParameters,
                 parameters: null,
                 returnType: getter.returnType);
             return existingSuggestion;
           }

           // Cache lone getter/setter so that it can be paired
           _syntheticMap[cacheKey] = suggestion;
         }
       }
       if (_completions.add(suggestion.completion)) {
         suggestions.add(suggestion);
       }
     }
     return suggestion;
   }
 }

 /**
  * This class creates suggestions based upon top-level elements.
  */
 class LibraryElementSuggestionBuilder extends SimpleElementVisitor
     with ElementSuggestionBuilder {
   final LibraryElement containingLibrary;
   final CompletionSuggestionKind kind;
   final bool typesOnly;
   final bool instCreation;

   LibraryElementSuggestionBuilder(
       this.containingLibrary, this.kind, this.typesOnly, this.instCreation);

   @override
   visitClassElement(ClassElement element) {
     if (instCreation) {
       element.visitChildren(this);
     } else {
       addSuggestion(element);
     }
   }

   @override
   visitConstructorElement(ConstructorElement element) {
     if (instCreation) {
       ClassElement classElem = element.enclosingElement;
       if (classElem != null) {
         String prefix = classElem.name;
         if (prefix != null && prefix.isNotEmpty) {
           addSuggestion(element, prefix: prefix);
         }
       }
     }
   }

   @override
   visitExtensionElement(ExtensionElement element) {
     if (!instCreation) {
       addSuggestion(element);
     }
   }

   @override
   visitFunctionElement(FunctionElement element) {
     if (!typesOnly) {
       int relevance = element.library == containingLibrary
           ? DART_RELEVANCE_LOCAL_FUNCTION
           : DART_RELEVANCE_DEFAULT;
       addSuggestion(element, relevance: relevance);
     }
   }

   @override
   visitFunctionTypeAliasElement(FunctionTypeAliasElement element) {
     if (!instCreation) {
       addSuggestion(element);
     }
   }

   @override
   visitPropertyAccessorElement(PropertyAccessorElement element) {
     if (!typesOnly) {
       PropertyInducingElement variable = element.variable;
       int relevance = variable.library == containingLibrary
           ? DART_RELEVANCE_LOCAL_TOP_LEVEL_VARIABLE
           : DART_RELEVANCE_DEFAULT;
       addSuggestion(variable, relevance: relevance);
     }
   }
 }

 /**
  * This class provides suggestions based upon the visible instance members in
  * an interface type.
  */
 class MemberSuggestionBuilder {
   /**
    * Enumerated value indicating that we have not generated any completions for
    * a given identifier yet.
    */
   static const int _COMPLETION_TYPE_NONE = 0;

   /**
    * Enumerated value indicating that we have generated a completion for a
    * getter.
    */
   static const int _COMPLETION_TYPE_GETTER = 1;

   /**
    * Enumerated value indicating that we have generated a completion for a
    * setter.
    */
   static const int _COMPLETION_TYPE_SETTER = 2;

   /**
    * Enumerated value indicating that we have generated a completion for a
    * field, a method, or a getter/setter pair.
    */
   static const int _COMPLETION_TYPE_FIELD_OR_METHOD_OR_GETSET = 3;

   /**
    * The library containing the unit in which the completion is requested.
    */
   final LibraryElement containingLibrary;

   /**
    * Map indicating, for each possible completion identifier, whether we have
    * already generated completions for a getter, setter, or both.  The "both"
    * case also handles the case where have generated a completion for a method
    * or a field.
    *
    * Note: the enumerated values stored in this map are intended to be bitwise
    * compared.
    */
   final Map<String, int> _completionTypesGenerated = new HashMap<String, int>();

   /**
    * Map from completion identifier to completion suggestion
    */
   final Map<String, CompletionSuggestion> _suggestionMap =
       <String, CompletionSuggestion>{};

   MemberSuggestionBuilder(this.containingLibrary);

   Iterable<CompletionSuggestion> get suggestions => _suggestionMap.values;

   /**
    * Add a suggestion based upon the given element, provided that it is not
    * shadowed by a previously added suggestion.
    */
   void addSuggestion(Element element,
       {int relevance = DART_RELEVANCE_DEFAULT}) {
     if (element.isPrivate) {
       if (element.library != containingLibrary) {
         // Do not suggest private members for imported libraries
         return;
       }
     }
     String identifier = element.displayName;

     if (relevance == DART_RELEVANCE_DEFAULT && identifier != null) {
       // Decrease relevance of suggestions starting with $
       // https://github.com/dart-lang/sdk/issues/27303
       if (identifier.startsWith(r'$')) {
         relevance = DART_RELEVANCE_LOW;
       }
     }

     int alreadyGenerated = _completionTypesGenerated.putIfAbsent(
         identifier, () => _COMPLETION_TYPE_NONE);
     if (element is MethodElement) {
       // Anything shadows a method.
       if (alreadyGenerated != _COMPLETION_TYPE_NONE) {
         return;
       }
       _completionTypesGenerated[identifier] =
           _COMPLETION_TYPE_FIELD_OR_METHOD_OR_GETSET;
     } else if (element is PropertyAccessorElement) {
       if (element.isGetter) {
         // Getters, fields, and methods shadow a getter.
         if ((alreadyGenerated & _COMPLETION_TYPE_GETTER) != 0) {
           return;
         }
         _completionTypesGenerated[identifier] |= _COMPLETION_TYPE_GETTER;
       } else {
         // Setters, fields, and methods shadow a setter.
         if ((alreadyGenerated & _COMPLETION_TYPE_SETTER) != 0) {
           return;
         }
         _completionTypesGenerated[identifier] |= _COMPLETION_TYPE_SETTER;
       }
     } else if (element is FieldElement) {
       // Fields and methods shadow a field.  A getter/setter pair shadows a
       // field, but a getter or setter by itself doesn't.
       if (alreadyGenerated == _COMPLETION_TYPE_FIELD_OR_METHOD_OR_GETSET) {
         return;
       }
       _completionTypesGenerated[identifier] =
           _COMPLETION_TYPE_FIELD_OR_METHOD_OR_GETSET;
     } else {
       // Unexpected element type; skip it.
       assert(false);
       return;
     }
     CompletionSuggestion suggestion =
         createSuggestion(element, relevance: relevance);
     if (suggestion != null) {
       _suggestionMap[suggestion.completion] = suggestion;
     }
   }
 }
	// Copyright (c) 2015, 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 'dart:collection';

	import 'package:analysis_server/src/protocol_server.dart' as protocol;
	import 'package:analysis_server/src/protocol_server.dart'
	hide Element, ElementKind;
	import 'package:analysis_server/src/provisional/completion/dart/completion_dart.dart';
	import 'package:analysis_server/src/services/completion/dart/utilities.dart';
	import 'package:analyzer/dart/element/element.dart';
	import 'package:analyzer/dart/element/type.dart';
	import 'package:analyzer/dart/element/visitor.dart';
	import 'package:analyzer/src/util/comment.dart';

	import '../../../protocol_server.dart' show CompletionSuggestion;

	/**
	* Return a suggestion based upon the given element or `null` if a suggestion
	* is not appropriate for the given element.
	*/
	CompletionSuggestion createSuggestion(Element element,
	{String completion,
	CompletionSuggestionKind kind = CompletionSuggestionKind.INVOCATION,
	int relevance = DART_RELEVANCE_DEFAULT}) {
	if (element == null) {
	return null;
	}
	if (element is ExecutableElement && element.isOperator) {
	// Do not include operators in suggestions
	return null;
	}
	if (completion == null) {
	completion = element.displayName;
	}
	bool isDeprecated = element.hasDeprecated;
	CompletionSuggestion suggestion = new CompletionSuggestion(
	kind,
	isDeprecated ? DART_RELEVANCE_LOW : relevance,
	completion,
	completion.length,
	0,
	isDeprecated,
	false);

	// Attach docs.
	String doc = getDartDocPlainText(element.documentationComment);
	suggestion.docComplete = doc;
	suggestion.docSummary = getDartDocSummary(doc);

	suggestion.element = protocol.convertElement(element);
	Element enclosingElement = element.enclosingElement;
	if (enclosingElement is ClassElement) {
	suggestion.declaringType = enclosingElement.displayName;
	}
	suggestion.returnType = getReturnTypeString(element);
	if (element is ExecutableElement && element is! PropertyAccessorElement) {
	suggestion.parameterNames = element.parameters
	.map((ParameterElement parameter) => parameter.name)
	.toList();
	suggestion.parameterTypes =
	element.parameters.map((ParameterElement parameter) {
	DartType paramType = parameter.type;
	// Gracefully degrade if type not resolved yet
	return paramType != null ? paramType.displayName : 'var';
	}).toList();

	Iterable<ParameterElement> requiredParameters = element.parameters
	.where((ParameterElement param) => param.isRequiredPositional);
	suggestion.requiredParameterCount = requiredParameters.length;

	Iterable<ParameterElement> namedParameters =
	element.parameters.where((ParameterElement param) => param.isNamed);
	suggestion.hasNamedParameters = namedParameters.isNotEmpty;

	addDefaultArgDetails(
	suggestion, element, requiredParameters, namedParameters);
	}
	return suggestion;
	}

	/**
	* Common mixin for sharing behavior.
	*/
	mixin ElementSuggestionBuilder {
	/**
	* A collection of completion suggestions.
	*/
	final List<CompletionSuggestion> suggestions = <CompletionSuggestion>[];

	/**
	* A set of existing completions used to prevent duplicate suggestions.
	*/
	final Set<String> _completions = new Set<String>();

	/**
	* A map of element names to suggestions for synthetic getters and setters.
	*/
	final Map<String, CompletionSuggestion> _syntheticMap =
	<String, CompletionSuggestion>{};

	/**
	* Return the library in which the completion is requested.
	*/
	LibraryElement get containingLibrary;

	/**
	* Return the kind of suggestions that should be built.
	*/
	CompletionSuggestionKind get kind;

	/**
	* Add a suggestion based upon the given element.
	*/
	CompletionSuggestion addSuggestion(Element element,
	{String prefix,
	int relevance = DART_RELEVANCE_DEFAULT,
	String elementCompletion}) {
	if (element.isPrivate) {
	if (element.library != containingLibrary) {
	return null;
	}
	}
	String completion = elementCompletion ?? element.displayName;
	if (prefix != null && prefix.isNotEmpty) {
	if (completion == null \|\| completion.isEmpty) {
	completion = prefix;
	} else {
	completion = '$prefix.$completion';
	}
	}
	if (completion == null \|\| completion.isEmpty) {
	return null;
	}
	CompletionSuggestion suggestion = createSuggestion(element,
	completion: completion, kind: kind, relevance: relevance);
	if (suggestion != null) {
	if (element.isSynthetic && element is PropertyAccessorElement) {
	String cacheKey;
	if (element.isGetter) {
	cacheKey = element.name;
	}
	if (element.isSetter) {
	cacheKey = element.name;
	cacheKey = cacheKey.substring(0, cacheKey.length - 1);
	}
	if (cacheKey != null) {
	CompletionSuggestion existingSuggestion = _syntheticMap[cacheKey];

	// Pair getter/setter by updating the existing suggestion
	if (existingSuggestion != null) {
	CompletionSuggestion getter =
	element.isGetter ? suggestion : existingSuggestion;
	protocol.ElementKind elemKind =
	element.enclosingElement is ClassElement
	? protocol.ElementKind.FIELD
	: protocol.ElementKind.TOP_LEVEL_VARIABLE;
	existingSuggestion.element = new protocol.Element(
	elemKind,
	existingSuggestion.element.name,
	existingSuggestion.element.flags,
	location: getter.element.location,
	typeParameters: getter.element.typeParameters,
	parameters: null,
	returnType: getter.returnType);
	return existingSuggestion;
	}

	// Cache lone getter/setter so that it can be paired
	_syntheticMap[cacheKey] = suggestion;
	}
	}
	if (_completions.add(suggestion.completion)) {
	suggestions.add(suggestion);
	}
	}
	return suggestion;
	}
	}

	/**
	* This class creates suggestions based upon top-level elements.
	*/
	class LibraryElementSuggestionBuilder extends SimpleElementVisitor
	with ElementSuggestionBuilder {
	final LibraryElement containingLibrary;
	final CompletionSuggestionKind kind;
	final bool typesOnly;
	final bool instCreation;

	LibraryElementSuggestionBuilder(
	this.containingLibrary, this.kind, this.typesOnly, this.instCreation);

	@override
	visitClassElement(ClassElement element) {
	if (instCreation) {
	element.visitChildren(this);
	} else {
	addSuggestion(element);
	}
	}

	@override
	visitConstructorElement(ConstructorElement element) {
	if (instCreation) {
	ClassElement classElem = element.enclosingElement;
	if (classElem != null) {
	String prefix = classElem.name;
	if (prefix != null && prefix.isNotEmpty) {
	addSuggestion(element, prefix: prefix);
	}
	}
	}
	}

	@override
	visitExtensionElement(ExtensionElement element) {
	if (!instCreation) {
	addSuggestion(element);
	}
	}

	@override
	visitFunctionElement(FunctionElement element) {
	if (!typesOnly) {
	int relevance = element.library == containingLibrary
	? DART_RELEVANCE_LOCAL_FUNCTION
	: DART_RELEVANCE_DEFAULT;
	addSuggestion(element, relevance: relevance);
	}
	}

	@override
	visitFunctionTypeAliasElement(FunctionTypeAliasElement element) {
	if (!instCreation) {
	addSuggestion(element);
	}
	}

	@override
	visitPropertyAccessorElement(PropertyAccessorElement element) {
	if (!typesOnly) {
	PropertyInducingElement variable = element.variable;
	int relevance = variable.library == containingLibrary
	? DART_RELEVANCE_LOCAL_TOP_LEVEL_VARIABLE
	: DART_RELEVANCE_DEFAULT;
	addSuggestion(variable, relevance: relevance);
	}
	}
	}

	/**
	* This class provides suggestions based upon the visible instance members in
	* an interface type.
	*/
	class MemberSuggestionBuilder {
	/**
	* Enumerated value indicating that we have not generated any completions for
	* a given identifier yet.
	*/
	static const int _COMPLETION_TYPE_NONE = 0;

	/**
	* Enumerated value indicating that we have generated a completion for a
	* getter.
	*/
	static const int _COMPLETION_TYPE_GETTER = 1;

	/**
	* Enumerated value indicating that we have generated a completion for a
	* setter.
	*/
	static const int _COMPLETION_TYPE_SETTER = 2;

	/**
	* Enumerated value indicating that we have generated a completion for a
	* field, a method, or a getter/setter pair.
	*/
	static const int _COMPLETION_TYPE_FIELD_OR_METHOD_OR_GETSET = 3;

	/**
	* The library containing the unit in which the completion is requested.
	*/
	final LibraryElement containingLibrary;

	/**
	* Map indicating, for each possible completion identifier, whether we have
	* already generated completions for a getter, setter, or both. The "both"
	* case also handles the case where have generated a completion for a method
	* or a field.
	*
	* Note: the enumerated values stored in this map are intended to be bitwise
	* compared.
	*/
	final Map<String, int> _completionTypesGenerated = new HashMap<String, int>();

	/**
	* Map from completion identifier to completion suggestion
	*/
	final Map<String, CompletionSuggestion> _suggestionMap =
	<String, CompletionSuggestion>{};

	MemberSuggestionBuilder(this.containingLibrary);

	Iterable<CompletionSuggestion> get suggestions => _suggestionMap.values;

	/**
	* Add a suggestion based upon the given element, provided that it is not
	* shadowed by a previously added suggestion.
	*/
	void addSuggestion(Element element,
	{int relevance = DART_RELEVANCE_DEFAULT}) {
	if (element.isPrivate) {
	if (element.library != containingLibrary) {
	// Do not suggest private members for imported libraries
	return;
	}
	}
	String identifier = element.displayName;

	if (relevance == DART_RELEVANCE_DEFAULT && identifier != null) {
	// Decrease relevance of suggestions starting with $
	// https://github.com/dart-lang/sdk/issues/27303
	if (identifier.startsWith(r'$')) {
	relevance = DART_RELEVANCE_LOW;
	}
	}

	int alreadyGenerated = _completionTypesGenerated.putIfAbsent(
	identifier, () => _COMPLETION_TYPE_NONE);
	if (element is MethodElement) {
	// Anything shadows a method.
	if (alreadyGenerated != _COMPLETION_TYPE_NONE) {
	return;
	}
	_completionTypesGenerated[identifier] =
	_COMPLETION_TYPE_FIELD_OR_METHOD_OR_GETSET;
	} else if (element is PropertyAccessorElement) {
	if (element.isGetter) {
	// Getters, fields, and methods shadow a getter.
	if ((alreadyGenerated & _COMPLETION_TYPE_GETTER) != 0) {
	return;
	}
	_completionTypesGenerated[identifier] \|= _COMPLETION_TYPE_GETTER;
	} else {
	// Setters, fields, and methods shadow a setter.
	if ((alreadyGenerated & _COMPLETION_TYPE_SETTER) != 0) {
	return;
	}
	_completionTypesGenerated[identifier] \|= _COMPLETION_TYPE_SETTER;
	}
	} else if (element is FieldElement) {
	// Fields and methods shadow a field. A getter/setter pair shadows a
	// field, but a getter or setter by itself doesn't.
	if (alreadyGenerated == _COMPLETION_TYPE_FIELD_OR_METHOD_OR_GETSET) {
	return;
	}
	_completionTypesGenerated[identifier] =
	_COMPLETION_TYPE_FIELD_OR_METHOD_OR_GETSET;
	} else {
	// Unexpected element type; skip it.
	assert(false);
	return;
	}
	CompletionSuggestion suggestion =
	createSuggestion(element, relevance: relevance);
	if (suggestion != null) {
	_suggestionMap[suggestion.completion] = suggestion;
	}
	}
	}