Elements. Remove V1 PrefixElement.

Change-Id: Ic4987ada9be6b44b2602a90998f29bee43c7f352
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/423440
Reviewed-by: Brian Wilkerson <[email protected]>
Commit-Queue: Konstantin Shcheglov <[email protected]>

Author: scheglov

pkg/analysis_server/lib/src/services/refactoring/legacy/rename.dart

@@ -169,7 +169,7 @@ abstract class RenameRefactoringImpl extends RefactoringImpl
       }
       return name;
     } else if (element is MockLibraryImportElement) {
-      var prefix = element.import.prefix?.element;
+      var prefix = element.import.prefix2?.element;
       if (prefix != null) {
         return prefix.displayName;
       }

pkg/analyzer/api.txt

@@ -2967,8 +2967,6 @@ package:analyzer/dart/constant/value.dart:
     toSymbolValue (method: String? Function())
     toTypeValue (method: DartType? Function())
 package:analyzer/dart/element/element.dart:
-  DeferredImportElementPrefix (class extends Object implements ImportElementPrefix, deprecated):
-    new (constructor: DeferredImportElementPrefix Function())
   DirectiveUri (class extends Object):
     new (constructor: DirectiveUri Function())
   DirectiveUriWithLibrary (class extends DirectiveUriWithSource):
@@ -3129,9 +3127,6 @@ package:analyzer/dart/element/element.dart:
   HideElementCombinator (class extends Object implements NamespaceCombinator):
     new (constructor: HideElementCombinator Function())
     hiddenNames (getter: List<String>)
-  ImportElementPrefix (class extends Object, deprecated):
-    new (constructor: ImportElementPrefix Function())
-    element (getter: PrefixElement)
   LibraryElement (class extends Object implements _ExistingElement, deprecated):
     new (constructor: LibraryElement Function())
     enclosingElement3 (getter: Null)
@@ -3163,7 +3158,6 @@ package:analyzer/dart/element/element.dart:
     importKeywordOffset (getter: int)
     importedLibrary (getter: LibraryElement?)
     namespace (getter: Namespace)
-    prefix (getter: ImportElementPrefix?, deprecated)
     uri (getter: DirectiveUri)
   LibraryLanguageVersion (class extends Object):
     new (constructor: LibraryLanguageVersion Function({required Version? override, required Version package}))
@@ -3203,11 +3197,6 @@ package:analyzer/dart/element/element.dart:
   PartElement (class extends Object implements _ExistingElement, deprecated):
     new (constructor: PartElement Function())
     uri (getter: DirectiveUri)
-  PrefixElement (class extends Object implements _ExistingElement, deprecated):
-    new (constructor: PrefixElement Function())
-    imports (getter: List<LibraryImportElement>)
-    name (getter: String)
-    scope (getter: Scope)
   PromotableElement (class extends Object implements LocalElement, VariableElement, deprecated):
     new (constructor: PromotableElement Function())
     name (getter: String)

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

@@ -42,7 +42,6 @@ import 'package:analyzer/dart/analysis/session.dart';
 import 'package:analyzer/dart/constant/value.dart';
 import 'package:analyzer/dart/element/element2.dart';
 import 'package:analyzer/dart/element/nullability_suffix.dart';
-import 'package:analyzer/dart/element/scope.dart';
 import 'package:analyzer/dart/element/type.dart';
 import 'package:analyzer/dart/element/type_provider.dart';
 import 'package:analyzer/dart/element/type_system.dart';
@@ -59,12 +58,6 @@ import 'package:analyzer/src/task/api/model.dart' show AnalysisTarget;
 import 'package:meta/meta.dart';
 import 'package:pub_semver/pub_semver.dart';
 
-/// [ImportElementPrefix] that is used together with `deferred`.
-///
-/// Clients may not extend, implement or mix-in this class.
-@Deprecated('Use PrefixElement2 instead')
-abstract class DeferredImportElementPrefix implements ImportElementPrefix {}
-
 /// Meaning of a URI referenced in a directive.
 ///
 /// Clients may not extend, implement or mix-in this class.
@@ -735,16 +728,6 @@ abstract class HideElementCombinator implements NamespaceCombinator {
   List<String> get hiddenNames;
 }
 
-/// Usage of a [PrefixElement] in an `import` directive.
-///
-/// Clients may not extend, implement or mix-in this class.
-@Deprecated('Use PrefixElement2 instead')
-abstract class ImportElementPrefix {
-  /// The prefix that was specified as part of the import directive, or `null`
-  /// if there was no prefix specified.
-  PrefixElement get element;
-}
-
 /// A library.
 ///
 /// Clients may not extend, implement or mix-in this class.
@@ -852,11 +835,6 @@ abstract class LibraryImportElement implements _ExistingElement {
   /// The [Namespace] that this directive contributes to the containing library.
   Namespace get namespace;
 
-  /// The prefix that was specified as part of the import directive, or `null`
-  /// if there was no prefix specified.
-  @Deprecated(elementModelDeprecationMsg)
-  ImportElementPrefix? get prefix;
-
   /// The interpretation of the URI specified in the directive.
   DirectiveUri get uri;
 }
@@ -1019,25 +997,6 @@ abstract class PartElement implements _ExistingElement {
   DirectiveUri get uri;
 }
 
-/// A prefix used to import one or more libraries into another library.
-///
-/// Clients may not extend, implement or mix-in this class.
-@Deprecated('Use PrefixElement2 instead')
-abstract class PrefixElement implements _ExistingElement {
-  /// The imports that share this prefix.
-  List<LibraryImportElement> get imports;
-
-  @override
-  String get name;
-
-  /// The name lookup scope for this import prefix.
-  ///
-  /// It consists of elements imported into the enclosing library with this
-  /// prefix. The namespace combinators of the import directives are taken
-  /// into account.
-  Scope get scope;
-}
-
 /// A variable that might be subject to type promotion.  This might be a local
 /// variable or a parameter.
 ///

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

@@ -100,7 +100,7 @@ import 'package:meta/meta.dart';
 // 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 = 453;
+  static const int DATA_VERSION = 454;
 
   /// 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/analysis/library_analyzer.dart

@@ -51,7 +51,6 @@ import 'package:analyzer/src/lint/analysis_rule_timers.dart';
 import 'package:analyzer/src/lint/linter.dart';
 import 'package:analyzer/src/lint/linter_visitor.dart';
 import 'package:analyzer/src/util/performance/operation_performance.dart';
-import 'package:analyzer/src/utilities/extensions/element.dart';
 import 'package:analyzer/src/utilities/extensions/version.dart';
 import 'package:analyzer/src/workspace/pub.dart';
 import 'package:analyzer/src/workspace/workspace.dart';
@@ -974,7 +973,7 @@ class LibraryAnalyzer {
     required ErrorReporter errorReporter,
   }) {
     directive.element = element;
-    directive.prefix?.element = element.prefix?.element.asElement2;
+    directive.prefix?.element = element.prefix2?.element;
     _resolveUriConfigurations(
       configurationNodes: directive.configurations,
       configurationUris: state.uris.configurations,

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

@@ -256,24 +256,6 @@ class ElementDisplayStringBuilder {
     _writeDirectiveUri(element.uri);
   }
 
-  void writePrefixElement(PrefixElementImpl element) {
-    var libraryImports = element.imports;
-    var displayName = element.displayName;
-    if (libraryImports.isEmpty) {
-      _write('as ');
-      _write(displayName);
-      return;
-    }
-    var first = libraryImports.first;
-    _write("import '${first.libraryName}' as $displayName;");
-    if (libraryImports.length == 1) {
-      return;
-    }
-    for (var libraryImport in libraryImports.sublist(1)) {
-      _write("\nimport '${libraryImport.libraryName}' as $displayName;");
-    }
-  }
-
   void writePrefixElement2(PrefixElementImpl2 element) {
     var libraryImports = element.imports;
     var displayName = element.displayName;