Support analyzer 6.x in analyzer plugin

Author: greglittlefield-wf

tools/analyzer_plugin/lib/src/diagnostic/exhaustive_deps.dart

@@ -680,7 +680,7 @@ class ExhaustiveDeps extends DiagnosticContributor {
         // NamedType case. This is for references to generic type parameters
         // (references to other types will get filtered out by the isDeclaredInPureScope check above).
         (reference) {
-          dependency = reference.name.name;
+          dependency = reference.nameLexeme;
           // These aren't possible for type annotations.
           isStable = false;
           isUsedAsCascadeTarget = false;
@@ -1980,7 +1980,7 @@ _Recommendations collectRecommendations({
 String? getConstructionExpressionType(Expression node) {
   if (node is InstanceCreationExpression) {
     if (node.isConst) return null;
-    return node.constructorName.type.name.name;
+    return node.constructorName.type.nameLexeme;
   } else if (node is ListLiteral) {
     return _DepType.list;
   } else if (node is SetOrMapLiteral) {
@@ -2365,3 +2365,20 @@ extension<E extends Comparable<dynamic>> on Iterable<E> {
     return true;
   }
 }
+
+extension TypeNameHelper on NamedType {
+  // Backwards compatibility for various analyzer versions that remove name/name2.
+  // ignore: unnecessary_this
+  dynamic get name => this.name2; // Use `this.` to point to real impl if it exists, not extension.
+  // ignore: unnecessary_this
+  dynamic get name2 => this.name; // Use `this.` to point to real impl if it exists, not extension.
+  dynamic get _name => name;
+
+  String get nameLexeme {
+    final name = _name;
+    if (name is Identifier) return name.name;
+    if (name is Token) return name.lexeme;
+    if (name is String) return name;
+    throw UnimplementedError('Unexpected type for name: ${name.runtimeType}');
+  }
+}

tools/analyzer_plugin/lib/src/diagnostic/visitors/non_static_reference_visitor.dart

@@ -70,7 +70,7 @@ bool referencesImplicitThis(SimpleIdentifier identifier) {
   }
   // not a class member
   final Element? enclosingElement = element.enclosingElement;
-  if (enclosingElement is! InterfaceOrAugmentationElement) {
+  if (enclosingElement is! InterfaceElement) {
     return false;
   }
   // comment

tools/analyzer_plugin/pubspec.yaml

@@ -6,7 +6,7 @@ repository: https://github.com/Workiva/over_react/tree/master/tools/analyzer_plu
 environment:
   sdk: '>=2.19.0 <3.0.0'
 dependencies:
-  analyzer: ^5.11.0
+  analyzer: '>=5.11.0 <7.0.0'
   analyzer_plugin: ^0.11.0
   collection: ^1.15.0-nullsafety.4
   meta: ^1.16.0

tools/analyzer_plugin/test/integration/stubs.dart

@@ -101,6 +101,7 @@ class StubServerPlugin implements ServerPlugin {
   handleEditGetRefactoring(parameters) => throw UnimplementedError();
 
   @override
+  // ignore: override_on_non_overriding_member
   handleKytheGetKytheEntries(parameters) => throw UnimplementedError();
 
   @override