[analyzer] Combine ElementUsageFrontierDetectors

Originally attempted to stab away at the cost of
https://dart-review.googlesource.com/c/sdk/+/478701 - and while it did
get better it was still much more expensive than before.

With https://dart-review.googlesource.com/c/sdk/+/478701 having been
reverted I've rebased and this is the new numbers:

Parent CL:

    42,517,120,185      instructions:u
    42,517,237,423      instructions:u
    42,514,559,436      instructions:u

This CL:

    41,687,688,230      instructions:u
    41,687,684,807      instructions:u
    41,687,673,825      instructions:u

Saves ~827 mio instructions

Change-Id: I752163a27dd779f27fafecce219cdc15e0f73d29
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/482241
Commit-Queue: Jens Johansen <jensj@google.com>
Reviewed-by: Paul Berry <paulberry@google.com>
Reviewed-by: Samuel Rawlins <srawlins@google.com>

pkg/analyzer/lib/src/error/best_practices_verifier.dart

@@ -26,6 +26,7 @@ import 'package:analyzer/src/error/deprecated_functionality_verifier.dart';
 import 'package:analyzer/src/error/deprecated_member_use_verifier.dart';
 import 'package:analyzer/src/error/do_not_submit_member_use_verifier.dart';
 import 'package:analyzer/src/error/doc_comment_verifier.dart';
+import 'package:analyzer/src/error/element_usage_detector.dart';
 import 'package:analyzer/src/error/element_usage_frontier_detector.dart';
 import 'package:analyzer/src/error/error_handler_verifier.dart';
 import 'package:analyzer/src/error/experimental_member_use_verifier.dart';
@@ -66,7 +67,7 @@ class BestPracticesVerifier extends RecursiveAstVisitor<void> {
 
   final DeprecatedFunctionalityVerifier _deprecatedFunctionalityVerifier;
 
-  final List<ElementUsageFrontierDetector> _elementUsageFrontierDetectors;
+  final ElementUsageFrontierDetector _elementUsageFrontierDetector;
 
   final ErrorHandlerVerifier _errorHandlerVerifier;
 
@@ -117,29 +118,29 @@ class BestPracticesVerifier extends RecursiveAstVisitor<void> {
          _diagnosticReporter,
          _currentLibrary,
        ),
-       _elementUsageFrontierDetectors = [
-         ElementUsageFrontierDetector(
-           workspacePackage: workspacePackage,
-           elementUsageSet: const DeprecatedElementUsageSet(),
-           elementUsageReporter: DeprecatedElementUsageReporter(
-             diagnosticReporter: _diagnosticReporter,
+       _elementUsageFrontierDetector = ElementUsageFrontierDetector(
+         workspacePackage: workspacePackage,
+         usagesAndReporters: [
+           UsageSetAndReporter(
+             const DeprecatedElementUsageSet(),
+             DeprecatedElementUsageReporter(
+               diagnosticReporter: _diagnosticReporter,
+             ),
            ),
-         ),
-         ElementUsageFrontierDetector(
-           workspacePackage: workspacePackage,
-           elementUsageSet: const ExperimentalElementUsageSet(),
-           elementUsageReporter: ExperimentalElementUsageReporter(
-             diagnosticReporter: _diagnosticReporter,
+           UsageSetAndReporter(
+             const ExperimentalElementUsageSet(),
+             ExperimentalElementUsageReporter(
+               diagnosticReporter: _diagnosticReporter,
+             ),
            ),
-         ),
-         ElementUsageFrontierDetector(
-           workspacePackage: workspacePackage,
-           elementUsageSet: const DoNotSubmitElementUsageSet(),
-           elementUsageReporter: DoNotSubmitElementUsageReporter(
-             diagnosticReporter: _diagnosticReporter,
+           UsageSetAndReporter(
+             const DoNotSubmitElementUsageSet(),
+             DoNotSubmitElementUsageReporter(
+               diagnosticReporter: _diagnosticReporter,
+             ),
            ),
-         ),
-       ],
+         ],
+       ),
        _errorHandlerVerifier = ErrorHandlerVerifier(
          _diagnosticReporter,
          typeProvider,
@@ -159,9 +160,7 @@ class BestPracticesVerifier extends RecursiveAstVisitor<void> {
        ),
        _widgetPreviewVerifier = WidgetPreviewVerifier(_diagnosticReporter),
        _workspacePackage = workspacePackage {
-    for (var v in _elementUsageFrontierDetectors) {
-      v.pushElement(_currentLibrary);
-    }
+    _elementUsageFrontierDetector.pushElement(_currentLibrary);
     _inDoNotStoreMember = _currentLibrary.metadata.hasDoNotStore;
   }
 
@@ -188,17 +187,13 @@ class BestPracticesVerifier extends RecursiveAstVisitor<void> {
 
   @override
   void visitAssignmentExpression(AssignmentExpression node) {
-    for (var v in _elementUsageFrontierDetectors) {
-      v.assignmentExpression(node);
-    }
+    _elementUsageFrontierDetector.assignmentExpression(node);
     super.visitAssignmentExpression(node);
   }
 
   @override
   void visitBinaryExpression(BinaryExpression node) {
-    for (var v in _elementUsageFrontierDetectors) {
-      v.binaryExpression(node);
-    }
+    _elementUsageFrontierDetector.binaryExpression(node);
     _checkForInvariantNanComparison(node);
     _checkForInvariantNullComparison(node);
     _invalidAccessVerifier.verifyBinary(node);
@@ -233,9 +228,7 @@ class BestPracticesVerifier extends RecursiveAstVisitor<void> {
 
     bool wasInDoNotStoreMember = _inDoNotStoreMember;
     _deprecatedFunctionalityVerifier.classDeclaration(node);
-    for (var v in _elementUsageFrontierDetectors) {
-      v.pushElement(element);
-    }
+    _elementUsageFrontierDetector.pushElement(element);
     if (element.metadata.hasDoNotStore) {
       _inDoNotStoreMember = true;
     }
@@ -250,9 +243,7 @@ class BestPracticesVerifier extends RecursiveAstVisitor<void> {
     } finally {
       _enclosingClass = null;
       _invalidAccessVerifier._enclosingClass = null;
-      for (var v in _elementUsageFrontierDetectors) {
-        v.popElement();
-      }
+      _elementUsageFrontierDetector.popElement();
       _inDoNotStoreMember = wasInDoNotStoreMember;
     }
   }
@@ -262,16 +253,12 @@ class BestPracticesVerifier extends RecursiveAstVisitor<void> {
     _immutableVerifier.checkDeclaration(node, nameToken: node.name);
     _checkForInvalidSealedSuperclass(node);
     _deprecatedFunctionalityVerifier.classTypeAlias(node);
-    for (var v in _elementUsageFrontierDetectors) {
-      v.pushElement(node.declaredFragment!.element);
-    }
+    _elementUsageFrontierDetector.pushElement(node.declaredFragment!.element);
 
     try {
       super.visitClassTypeAlias(node);
     } finally {
-      for (var v in _elementUsageFrontierDetectors) {
-        v.popElement();
-      }
+      _elementUsageFrontierDetector.popElement();
     }
   }
 
@@ -314,29 +301,21 @@ class BestPracticesVerifier extends RecursiveAstVisitor<void> {
       initializers: node.initializers,
     );
     var element = node.declaredFragment!.element;
-    for (var v in _elementUsageFrontierDetectors) {
-      v.pushElement(element);
-    }
-    for (var v in _elementUsageFrontierDetectors) {
-      v.constructorDeclaration(node);
-    }
+    _elementUsageFrontierDetector.pushElement(element);
+    _elementUsageFrontierDetector.constructorDeclaration(node);
 
     _deprecatedFunctionalityVerifier.constructorDeclaration(node);
 
     try {
       super.visitConstructorDeclaration(node);
     } finally {
-      for (var v in _elementUsageFrontierDetectors) {
-        v.popElement();
-      }
+      _elementUsageFrontierDetector.popElement();
     }
   }
 
   @override
   void visitConstructorName(ConstructorName node) {
-    for (var v in _elementUsageFrontierDetectors) {
-      v.constructorName(node);
-    }
+    _elementUsageFrontierDetector.constructorName(node);
     _deprecatedFunctionalityVerifier.constructorName(node);
     super.visitConstructorName(node);
   }
@@ -359,20 +338,13 @@ class BestPracticesVerifier extends RecursiveAstVisitor<void> {
         );
       }
     }
-    for (var v in _elementUsageFrontierDetectors) {
-      v.pushElement(node.declaredFragment!.element);
-    }
-
-    for (var v in _elementUsageFrontierDetectors) {
-      v.formalParameter(node);
-    }
+    _elementUsageFrontierDetector.pushElement(node.declaredFragment!.element);
+    _elementUsageFrontierDetector.formalParameter(node);
 
     try {
       super.visitDefaultFormalParameter(node);
     } finally {
-      for (var v in _elementUsageFrontierDetectors) {
-        v.popElement();
-      }
+      _elementUsageFrontierDetector.popElement();
     }
   }
 
@@ -381,9 +353,7 @@ class BestPracticesVerifier extends RecursiveAstVisitor<void> {
     DotShorthandConstructorInvocation node,
   ) {
     _deprecatedFunctionalityVerifier.dotShorthandConstructorInvocation(node);
-    for (var v in _elementUsageFrontierDetectors) {
-      v.dotShorthandConstructorInvocation(node);
-    }
+    _elementUsageFrontierDetector.dotShorthandConstructorInvocation(node);
     _checkForLiteralConstructorUseInDotShorthand(node);
     super.visitDotShorthandConstructorInvocation(node);
   }
@@ -391,41 +361,31 @@ class BestPracticesVerifier extends RecursiveAstVisitor<void> {
   @override
   void visitDotShorthandInvocation(DotShorthandInvocation node) {
     _deprecatedFunctionalityVerifier.dotShorthandInvocation(node);
-    for (var v in _elementUsageFrontierDetectors) {
-      v.dotShorthandInvocation(node);
-    }
+    _elementUsageFrontierDetector.dotShorthandInvocation(node);
     super.visitDotShorthandInvocation(node);
   }
 
   @override
   void visitDotShorthandPropertyAccess(DotShorthandPropertyAccess node) {
-    for (var v in _elementUsageFrontierDetectors) {
-      v.dotShorthandPropertyAccess(node);
-    }
+    _elementUsageFrontierDetector.dotShorthandPropertyAccess(node);
     super.visitDotShorthandPropertyAccess(node);
   }
 
   @override
   void visitEnumDeclaration(EnumDeclaration node) {
-    for (var v in _elementUsageFrontierDetectors) {
-      v.pushElement(node.declaredFragment!.element);
-    }
+    _elementUsageFrontierDetector.pushElement(node.declaredFragment!.element);
     _deprecatedFunctionalityVerifier.enumDeclaration(node);
 
     try {
       super.visitEnumDeclaration(node);
     } finally {
-      for (var v in _elementUsageFrontierDetectors) {
-        v.popElement();
-      }
+      _elementUsageFrontierDetector.popElement();
     }
   }
 
   @override
   void visitExportDirective(covariant ExportDirectiveImpl node) {
-    for (var v in _elementUsageFrontierDetectors) {
-      v.exportDirective(node);
-    }
+    _elementUsageFrontierDetector.exportDirective(node);
     _checkForInternalExport(node);
     super.visitExportDirective(node);
   }
@@ -440,47 +400,35 @@ class BestPracticesVerifier extends RecursiveAstVisitor<void> {
 
   @override
   void visitExtensionDeclaration(ExtensionDeclaration node) {
-    for (var v in _elementUsageFrontierDetectors) {
-      v.pushElement(node.declaredFragment!.element);
-    }
+    _elementUsageFrontierDetector.pushElement(node.declaredFragment!.element);
 
     try {
       super.visitExtensionDeclaration(node);
     } finally {
-      for (var v in _elementUsageFrontierDetectors) {
-        v.popElement();
-      }
+      _elementUsageFrontierDetector.popElement();
     }
   }
 
   @override
   void visitExtensionOverride(ExtensionOverride node) {
-    for (var v in _elementUsageFrontierDetectors) {
-      v.extensionOverride(node);
-    }
+    _elementUsageFrontierDetector.extensionOverride(node);
     super.visitExtensionOverride(node);
   }
 
   @override
   void visitExtensionTypeDeclaration(ExtensionTypeDeclaration node) {
-    for (var v in _elementUsageFrontierDetectors) {
-      v.pushElement(node.declaredFragment!.element);
-    }
+    _elementUsageFrontierDetector.pushElement(node.declaredFragment!.element);
 
     try {
       super.visitExtensionTypeDeclaration(node);
     } finally {
-      for (var v in _elementUsageFrontierDetectors) {
-        v.popElement();
-      }
+      _elementUsageFrontierDetector.popElement();
     }
   }
 
   @override
   void visitFieldDeclaration(FieldDeclaration node) {
-    for (var v in _elementUsageFrontierDetectors) {
-      v.pushElement(node.firstVariableElement);
-    }
+    _elementUsageFrontierDetector.pushElement(node.firstVariableElement);
 
     try {
       super.visitFieldDeclaration(node);
@@ -522,9 +470,7 @@ class BestPracticesVerifier extends RecursiveAstVisitor<void> {
         }
       }
     } finally {
-      for (var v in _elementUsageFrontierDetectors) {
-        v.popElement();
-      }
+      _elementUsageFrontierDetector.popElement();
     }
   }
 
@@ -538,9 +484,7 @@ class BestPracticesVerifier extends RecursiveAstVisitor<void> {
   void visitFunctionDeclaration(FunctionDeclaration node) {
     bool wasInDoNotStoreMember = _inDoNotStoreMember;
     var element = node.declaredFragment!.element;
-    for (var v in _elementUsageFrontierDetectors) {
-      v.pushElement(element);
-    }
+    _elementUsageFrontierDetector.pushElement(element);
     if (element.metadata.hasDoNotStore) {
       _inDoNotStoreMember = true;
     }
@@ -559,9 +503,7 @@ class BestPracticesVerifier extends RecursiveAstVisitor<void> {
       );
       super.visitFunctionDeclaration(node);
     } finally {
-      for (var v in _elementUsageFrontierDetectors) {
-        v.popElement();
-      }
+      _elementUsageFrontierDetector.popElement();
       _inDoNotStoreMember = wasInDoNotStoreMember;
     }
   }
@@ -585,9 +527,7 @@ class BestPracticesVerifier extends RecursiveAstVisitor<void> {
 
   @override
   void visitFunctionExpressionInvocation(FunctionExpressionInvocation node) {
-    for (var v in _elementUsageFrontierDetectors) {
-      v.functionExpressionInvocation(node);
-    }
+    _elementUsageFrontierDetector.functionExpressionInvocation(node);
     super.visitFunctionExpressionInvocation(node);
   }
 
@@ -595,16 +535,12 @@ class BestPracticesVerifier extends RecursiveAstVisitor<void> {
   void visitFunctionTypeAlias(FunctionTypeAlias node) {
     _checkStrictInferenceReturnType(node.returnType, node, node.name.lexeme);
     _checkStrictInferenceInParameters(node.parameters);
-    for (var v in _elementUsageFrontierDetectors) {
-      v.pushElement(node.declaredFragment!.element);
-    }
+    _elementUsageFrontierDetector.pushElement(node.declaredFragment!.element);
 
     try {
       super.visitFunctionTypeAlias(node);
     } finally {
-      for (var v in _elementUsageFrontierDetectors) {
-        v.popElement();
-      }
+      _elementUsageFrontierDetector.popElement();
     }
   }
 
@@ -634,24 +570,18 @@ class BestPracticesVerifier extends RecursiveAstVisitor<void> {
         node.name.lexeme,
       );
     }
-    for (var v in _elementUsageFrontierDetectors) {
-      v.pushElement(node.declaredFragment!.element);
-    }
+    _elementUsageFrontierDetector.pushElement(node.declaredFragment!.element);
 
     try {
       super.visitGenericTypeAlias(node);
     } finally {
-      for (var v in _elementUsageFrontierDetectors) {
-        v.popElement();
-      }
+      _elementUsageFrontierDetector.popElement();
     }
   }
 
   @override
   void visitImportDirective(ImportDirective node) {
-    for (var v in _elementUsageFrontierDetectors) {
-      v.importDirective(node);
-    }
+    _elementUsageFrontierDetector.importDirective(node);
     var import = node.libraryImport;
     if (import != null && import.prefix?.isDeferred == true) {
       _checkForLoadLibraryFunction(node, import);
@@ -662,9 +592,7 @@ class BestPracticesVerifier extends RecursiveAstVisitor<void> {
 
   @override
   void visitIndexExpression(IndexExpression node) {
-    for (var v in _elementUsageFrontierDetectors) {
-      v.indexExpression(node);
-    }
+    _elementUsageFrontierDetector.indexExpression(node);
     super.visitIndexExpression(node);
   }
 
@@ -672,9 +600,7 @@ class BestPracticesVerifier extends RecursiveAstVisitor<void> {
   void visitInstanceCreationExpression(
     covariant InstanceCreationExpressionImpl node,
   ) {
-    for (var v in _elementUsageFrontierDetectors) {
-      v.instanceCreationExpression(node);
-    }
+    _elementUsageFrontierDetector.instanceCreationExpression(node);
     _deprecatedFunctionalityVerifier.instanceCreationExpression(node);
     _nullSafeApiVerifier.instanceCreation(node);
     _checkForLiteralConstructorUse(node);
@@ -694,9 +620,7 @@ class BestPracticesVerifier extends RecursiveAstVisitor<void> {
     var element = node.declaredFragment!.element;
     var enclosingElement = element.enclosingElement;
 
-    for (var v in _elementUsageFrontierDetectors) {
-      v.pushElement(element);
-    }
+    _elementUsageFrontierDetector.pushElement(element);
     if (element.metadata.hasDoNotStore) {
       _inDoNotStoreMember = true;
     }
@@ -776,18 +700,14 @@ class BestPracticesVerifier extends RecursiveAstVisitor<void> {
 
       super.visitMethodDeclaration(node);
     } finally {
-      for (var v in _elementUsageFrontierDetectors) {
-        v.popElement();
-      }
+      _elementUsageFrontierDetector.popElement();
       _inDoNotStoreMember = wasInDoNotStoreMember;
     }
   }
 
   @override
   void visitMethodInvocation(covariant MethodInvocationImpl node) {
-    for (var v in _elementUsageFrontierDetectors) {
-      v.methodInvocation(node);
-    }
+    _elementUsageFrontierDetector.methodInvocation(node);
     _deprecatedFunctionalityVerifier.methodInvocation(node);
     _errorHandlerVerifier.verifyMethodInvocation(node);
     _nullSafeApiVerifier.methodInvocation(node);
@@ -802,9 +722,7 @@ class BestPracticesVerifier extends RecursiveAstVisitor<void> {
     _invalidAccessVerifier._enclosingClass = _enclosingClass;
 
     _deprecatedFunctionalityVerifier.mixinDeclaration(node);
-    for (var v in _elementUsageFrontierDetectors) {
-      v.pushElement(element);
-    }
+    _elementUsageFrontierDetector.pushElement(element);
 
     try {
       _immutableVerifier.checkDeclaration(node, nameToken: node.name);
@@ -813,17 +731,13 @@ class BestPracticesVerifier extends RecursiveAstVisitor<void> {
     } finally {
       _enclosingClass = null;
       _invalidAccessVerifier._enclosingClass = null;
-      for (var v in _elementUsageFrontierDetectors) {
-        v.popElement();
-      }
+      _elementUsageFrontierDetector.popElement();
     }
   }
 
   @override
   void visitNamedType(NamedType node) {
-    for (var v in _elementUsageFrontierDetectors) {
-      v.namedType(node);
-    }
+    _elementUsageFrontierDetector.namedType(node);
     _invalidAccessVerifier.verifyNamedType(node);
     var question = node.question;
     if (question != null) {
@@ -845,18 +759,14 @@ class BestPracticesVerifier extends RecursiveAstVisitor<void> {
 
   @override
   void visitPatternField(PatternField node) {
-    for (var v in _elementUsageFrontierDetectors) {
-      v.patternField(node);
-    }
+    _elementUsageFrontierDetector.patternField(node);
     _invalidAccessVerifier.verifyPatternField(node as PatternFieldImpl);
     super.visitPatternField(node);
   }
 
   @override
   void visitPostfixExpression(PostfixExpression node) {
-    for (var v in _elementUsageFrontierDetectors) {
-      v.postfixExpression(node);
-    }
+    _elementUsageFrontierDetector.postfixExpression(node);
     if (node.operator.type == TokenType.BANG &&
         node.operand.typeOrThrow.isDartCoreNull) {
       _diagnosticReporter.report(diag.nullCheckAlwaysFails.at(node));
@@ -866,23 +776,17 @@ class BestPracticesVerifier extends RecursiveAstVisitor<void> {
 
   @override
   void visitPrefixExpression(PrefixExpression node) {
-    for (var v in _elementUsageFrontierDetectors) {
-      v.prefixExpression(node);
-    }
+    _elementUsageFrontierDetector.prefixExpression(node);
     super.visitPrefixExpression(node);
   }
 
   @override
   void visitPrimaryConstructorBody(PrimaryConstructorBody node) {
     var element = node.declaration?.declaredFragment!.element;
-    for (var v in _elementUsageFrontierDetectors) {
-      v.pushElement(element);
-    }
+    _elementUsageFrontierDetector.pushElement(element);
     // TODO(srawlins): Account for @doNotStore, as in `visitFunctionDeclaration`.
     super.visitPrimaryConstructorBody(node);
-    for (var v in _elementUsageFrontierDetectors) {
-      v.popElement();
-    }
+    _elementUsageFrontierDetector.popElement();
   }
 
   @override
@@ -896,9 +800,7 @@ class BestPracticesVerifier extends RecursiveAstVisitor<void> {
   void visitRedirectingConstructorInvocation(
     RedirectingConstructorInvocation node,
   ) {
-    for (var v in _elementUsageFrontierDetectors) {
-      v.redirectingConstructorInvocation(node);
-    }
+    _elementUsageFrontierDetector.redirectingConstructorInvocation(node);
     super.visitRedirectingConstructorInvocation(node);
   }
 
@@ -918,55 +820,40 @@ class BestPracticesVerifier extends RecursiveAstVisitor<void> {
 
   @override
   void visitSimpleFormalParameter(SimpleFormalParameter node) {
-    for (var v in _elementUsageFrontierDetectors) {
-      v.pushElement(node.declaredFragment!.element);
-    }
-
-    for (var v in _elementUsageFrontierDetectors) {
-      v.formalParameter(node);
-    }
+    _elementUsageFrontierDetector.pushElement(node.declaredFragment!.element);
+    _elementUsageFrontierDetector.formalParameter(node);
 
     try {
       super.visitSimpleFormalParameter(node);
     } finally {
-      for (var v in _elementUsageFrontierDetectors) {
-        v.popElement();
-      }
+      _elementUsageFrontierDetector.popElement();
     }
   }
 
   @override
   void visitSimpleIdentifier(SimpleIdentifier node) {
-    for (var v in _elementUsageFrontierDetectors) {
-      v.simpleIdentifier(node);
-    }
+    _elementUsageFrontierDetector.simpleIdentifier(node);
     _invalidAccessVerifier.verify(node);
     super.visitSimpleIdentifier(node);
   }
 
   @override
   void visitSuperConstructorInvocation(SuperConstructorInvocation node) {
-    for (var v in _elementUsageFrontierDetectors) {
-      v.superConstructorInvocation(node);
-    }
+    _elementUsageFrontierDetector.superConstructorInvocation(node);
     _invalidAccessVerifier.verifySuperConstructorInvocation(node);
     super.visitSuperConstructorInvocation(node);
   }
 
   @override
   void visitSuperFormalParameter(SuperFormalParameter node) {
-    for (var v in _elementUsageFrontierDetectors) {
-      v.superFormalParameter(node);
-    }
+    _elementUsageFrontierDetector.superFormalParameter(node);
     _checkFinalParameter(node, node.keyword);
     super.visitSuperFormalParameter(node);
   }
 
   @override
   void visitTopLevelVariableDeclaration(TopLevelVariableDeclaration node) {
-    for (var v in _elementUsageFrontierDetectors) {
-      v.pushElement(node.firstVariableElement);
-    }
+    _elementUsageFrontierDetector.pushElement(node.firstVariableElement);
 
     if (!_invalidAccessVerifier._inTestDirectory) {
       for (var decl in node.variables.variables) {
@@ -977,9 +864,7 @@ class BestPracticesVerifier extends RecursiveAstVisitor<void> {
     try {
       super.visitTopLevelVariableDeclaration(node);
     } finally {
-      for (var v in _elementUsageFrontierDetectors) {
-        v.popElement();
-      }
+      _elementUsageFrontierDetector.popElement();
     }
   }
 

pkg/analyzer/lib/src/error/deprecated_member_use_verifier.dart

@@ -63,12 +63,15 @@ class DeprecatedElementUsageReporter implements ElementUsageReporter<String> {
 class DeprecatedElementUsageSet implements ElementUsageSet<String> {
   const DeprecatedElementUsageSet();
 
-  /// The message in the deprecated annotation on the given [element], or
+  @override
+  bool get reliesOnlyOnElementMetadata => true;
+
+  /// The message in the deprecated annotation in [elementMetadata], or
   /// the empty string if the annotation does not have a message, or `null` if
   /// the element doesn't have a deprecated annotation.
   @override
-  String? getTagInfo(Element element) {
-    for (var annotation in element.metadata.annotations) {
+  String? getTagInfo(Element _, Metadata elementMetadata) {
+    for (var annotation in elementMetadata.annotations) {
       if (!annotation.isDeprecated) continue;
       var value = annotation.computeConstantValue();
       if (value == null) continue;

pkg/analyzer/lib/src/error/do_not_submit_member_use_verifier.dart

@@ -37,6 +37,9 @@ class DoNotSubmitElementUsageSet implements ElementUsageSet<()> {
   const DoNotSubmitElementUsageSet();
 
   @override
-  ()? getTagInfo(Element element) =>
-      element.metadata.hasDoNotSubmit ? () : null;
+  bool get reliesOnlyOnElementMetadata => true;
+
+  @override
+  ()? getTagInfo(Element _, Metadata elementMetadata) =>
+      elementMetadata.hasDoNotSubmit ? () : null;
 }

pkg/analyzer/lib/src/error/element_usage_detector.dart

@@ -24,17 +24,21 @@ class ElementUsageDetector<TagInfo extends Object> {
   /// parameter of [ElementUsageReporter.report].
   final WorkspacePackage? _workspacePackage;
 
-  /// The set of elements to detect usages of.
-  final ElementUsageSet<TagInfo> elementUsageSet;
-
-  /// What to do when a usage of an element in [elementUsageSet] is detected.
-  final ElementUsageReporter<TagInfo> elementUsageReporter;
+  final List<UsageSetAndReporter> usagesArbitrary = [];
+  final List<UsageSetAndReporter> usagesMetadataOnly = [];
 
   ElementUsageDetector({
     required WorkspacePackage? workspacePackage,
-    required this.elementUsageSet,
-    required this.elementUsageReporter,
-  }) : _workspacePackage = workspacePackage;
+    required List<UsageSetAndReporter> usagesAndReporters,
+  }) : _workspacePackage = workspacePackage {
+    for (var usageSetAndReporter in usagesAndReporters) {
+      if (usageSetAndReporter.elementUsageSet.reliesOnlyOnElementMetadata) {
+        usagesMetadataOnly.add(usageSetAndReporter);
+      } else {
+        usagesArbitrary.add(usageSetAndReporter);
+      }
+    }
+  }
 
   void assignmentExpression(AssignmentExpression node) {
     checkUsage(node.readElement, node.leftHandSide);
@@ -47,7 +51,7 @@ class ElementUsageDetector<TagInfo extends Object> {
   }
 
   /// Reports the usage of [element] at [node] if [element] is in
-  /// [elementUsageSet].
+  /// any of [usagesMetadataOnly] or [usagesArbitrary].
   void checkUsage(Element? element, AstNode node) {
     if (element == null) {
       return;
@@ -61,8 +65,33 @@ class ElementUsageDetector<TagInfo extends Object> {
       return;
     }
 
-    var tagInfo = elementUsageSet.getTagInfo(element);
-    if (tagInfo == null) return;
+    List<UsageSetAndReporter>? givesNonNullResults;
+    var elementMetadata = element.metadata;
+    if (elementMetadata.annotations.isNotEmpty) {
+      for (int i = 0; i < usagesMetadataOnly.length; i++) {
+        if (!shouldCheckMetadataOnlyForIndex(i)) continue;
+        var usagesAndReporter = usagesMetadataOnly[i];
+        var tagInfo = usagesAndReporter.elementUsageSet.getTagInfo(
+          element,
+          elementMetadata,
+        );
+        if (tagInfo != null) {
+          (givesNonNullResults ??= []).add(usagesAndReporter);
+        }
+      }
+    }
+    for (int i = 0; i < usagesArbitrary.length; i++) {
+      if (!shouldCheckArbitraryForIndex(i)) continue;
+      var usagesAndReporter = usagesArbitrary[i];
+      var tagInfo = usagesAndReporter.elementUsageSet.getTagInfo(
+        element,
+        elementMetadata,
+      );
+      if (tagInfo != null) {
+        (givesNonNullResults ??= []).add(usagesAndReporter);
+      }
+    }
+    if (givesNonNullResults == null) return;
 
     if (_isLocalParameter(element, node)) {
       return;
@@ -120,12 +149,15 @@ class ElementUsageDetector<TagInfo extends Object> {
     // `ConstructorDeclaration.errorRange` here. This would stray from the API
     // of passing a SyntacticEntity here.
 
-    elementUsageReporter.report(
-      errorEntity,
-      displayName,
-      tagInfo,
-      isInSamePackage: _isLibraryInWorkspacePackage(element.library),
-    );
+    for (var reportThis in givesNonNullResults) {
+      reportThis.elementUsageReporter.report(
+        errorEntity,
+        displayName,
+        // Getting it again might not be ideal...
+        reportThis.elementUsageSet.getTagInfo(element, elementMetadata)!,
+        isInSamePackage: _isLibraryInWorkspacePackage(element.library),
+      );
+    }
   }
 
   void constructorDeclaration(ConstructorDeclaration node) {
@@ -266,6 +298,18 @@ class ElementUsageDetector<TagInfo extends Object> {
     _invocationArguments(node.element, node.argumentList);
   }
 
+  /// If false [checkUsage] may skip the call to `getTagInfo` on the [i]th
+  /// entry of [usagesArbitrary].
+  bool shouldCheckArbitraryForIndex(int i) {
+    return true;
+  }
+
+  /// If false [checkUsage] may skip the call to `getTagInfo` on the [i]th
+  /// entry of [usagesMetadataOnly].
+  bool shouldCheckMetadataOnlyForIndex(int i) {
+    return true;
+  }
+
   void simpleIdentifier(SimpleIdentifier node) {
     // Don't report declared identifiers.
     if (node.inDeclarationContext()) {
@@ -426,12 +470,28 @@ abstract class ElementUsageReporter<TagInfo extends Object> {
 /// string). If there is no auxiliary information, supply `()` for this type
 /// parameter.
 abstract class ElementUsageSet<TagInfo extends Object> {
+  /// If [getTagInfo] only relies on the element metadata and can only return
+  /// non-null if the metadata is not empty.
+  ///
+  /// Used to skip calls to [getTagInfo] is there is no metadata.
+  bool get reliesOnlyOnElementMetadata;
+
   /// If [element] is in the set of elements that [ElementUsageDetector] should
   /// detect usages of, returns auxiliary information associated with [element].
   ///
+  /// [elementMetadata] is the result of [element].metadata, but should be used
+  /// to avoid the overhead of asking again.
+  ///
   /// Otherwise returns `null`.
   ///
   /// For example, [DeprecatedElementUsageSet]'s implementation of this method
   /// returns the deprecation message if [element] is deprecated.
-  TagInfo? getTagInfo(Element element);
+  TagInfo? getTagInfo(Element element, Metadata elementMetadata);
+}
+
+class UsageSetAndReporter<TagInfo extends Object> {
+  final ElementUsageSet<TagInfo> elementUsageSet;
+  final ElementUsageReporter<TagInfo> elementUsageReporter;
+
+  UsageSetAndReporter(this.elementUsageSet, this.elementUsageReporter);
 }

pkg/analyzer/lib/src/error/element_usage_frontier_detector.dart

@@ -13,35 +13,96 @@ import 'package:analyzer/src/error/element_usage_detector.dart';
 /// that _are_ in the set.
 class ElementUsageFrontierDetector<TagInfo extends Object>
     extends ElementUsageDetector<TagInfo> {
-  /// Stack corresponding to elements being visited that might be in
-  /// [elementUsageSet].
+  /// Stack corresponding to elements being visited that might be in ith
+  /// [usagesArbitrary], i.e. the first index corresponds to [usagesArbitrary]
+  /// and the second index to the stack depth.
   ///
-  /// Each element indicates whether the corresponding element is in
-  /// [elementUsageSet] or not.
-  final List<bool> _inElementStack = [false];
+  /// Each element indicates whether the corresponding element is in ith
+  /// [usagesArbitrary] or not.
+  final List<List<bool>> _inElementStacksArbitrary = [];
+
+  /// Stack corresponding to elements being visited that might be in ith
+  /// [usagesMetadataOnly], i.e. the first index corresponds to
+  /// [usagesMetadataOnly] and the second index to the stack depth.
+  ///
+  /// Each element indicates whether the corresponding element is in ith
+  /// [usagesMetadataOnly] or not.
+  final List<List<bool>> _inElementStacksMetadataOnly = [];
 
   ElementUsageFrontierDetector({
     required super.workspacePackage,
-    required super.elementUsageSet,
-    required super.elementUsageReporter,
-  });
+    required super.usagesAndReporters,
+  }) {
+    for (int i = 0; i < usagesArbitrary.length; i++) {
+      _inElementStacksArbitrary.add([false]);
+    }
+    for (int i = 0; i < usagesMetadataOnly.length; i++) {
+      _inElementStacksMetadataOnly.add([false]);
+    }
+  }
 
   @override
   void checkUsage(Element? element, AstNode node) {
-    if (_inElementStack.last) {
-      return;
+    bool allTrue = true;
+    for (var inElementStack in _inElementStacksArbitrary) {
+      if (!inElementStack.last) {
+        allTrue = false;
+        break;
+      }
     }
+    if (allTrue) {
+      for (var inElementStack in _inElementStacksMetadataOnly) {
+        if (!inElementStack.last) {
+          allTrue = false;
+          break;
+        }
+      }
+    }
+    if (allTrue) return;
 
     super.checkUsage(element, node);
   }
 
   void popElement() {
-    _inElementStack.removeLast();
+    for (var inElementStack in _inElementStacksArbitrary) {
+      inElementStack.removeLast();
+    }
+    for (var inElementStack in _inElementStacksMetadataOnly) {
+      inElementStack.removeLast();
+    }
   }
 
   void pushElement(Element? element) {
-    var value = element != null && elementUsageSet.getTagInfo(element) != null;
-    var newValue = _inElementStack.last || value;
-    _inElementStack.add(newValue);
+    var elementMetadata = element?.metadata;
+    for (int i = 0; i < _inElementStacksArbitrary.length; i++) {
+      var inElementStack = _inElementStacksArbitrary[i];
+      var newValue = inElementStack.last;
+      if (!newValue && element != null) {
+        var elementUsageSet = usagesArbitrary[i].elementUsageSet;
+        newValue =
+            elementUsageSet.getTagInfo(element, elementMetadata!) != null;
+      }
+      inElementStack.add(newValue);
+    }
+    for (int i = 0; i < _inElementStacksMetadataOnly.length; i++) {
+      var inElementStack = _inElementStacksMetadataOnly[i];
+      var newValue = inElementStack.last;
+      if (!newValue && element != null) {
+        var elementUsageSet = usagesMetadataOnly[i].elementUsageSet;
+        newValue =
+            elementUsageSet.getTagInfo(element, elementMetadata!) != null;
+      }
+      inElementStack.add(newValue);
+    }
+  }
+
+  @override
+  bool shouldCheckArbitraryForIndex(int i) {
+    return !_inElementStacksArbitrary[i].last;
+  }
+
+  @override
+  bool shouldCheckMetadataOnlyForIndex(int i) {
+    return !_inElementStacksMetadataOnly[i].last;
   }
 }

pkg/analyzer/lib/src/error/experimental_member_use_verifier.dart

@@ -40,6 +40,9 @@ class ExperimentalElementUsageSet implements ElementUsageSet<()> {
   const ExperimentalElementUsageSet();
 
   @override
-  ()? getTagInfo(Element element) =>
-      element.metadata.annotations.any((e) => e.isExperimental) ? () : null;
+  bool get reliesOnlyOnElementMetadata => true;
+
+  @override
+  ()? getTagInfo(Element _, Metadata elementMetadata) =>
+      elementMetadata.annotations.any((e) => e.isExperimental) ? () : null;
 }

pkg/linter/lib/src/rules/deprecated_member_use_from_same_package.dart

@@ -16,7 +16,7 @@ import 'package:analyzer/error/error.dart';
 import 'package:analyzer/src/error/deprecated_member_use_verifier.dart' // ignore: implementation_imports
     show DeprecatedElementUsageSet, normalizeDeprecationMessage;
 import 'package:analyzer/src/error/element_usage_detector.dart' // ignore: implementation_imports
-    show ElementUsageReporter;
+    show ElementUsageReporter, UsageSetAndReporter;
 import 'package:analyzer/src/error/element_usage_frontier_detector.dart' // ignore: implementation_imports
     show ElementUsageFrontierDetector;
 import 'package:analyzer/src/utilities/extensions/ast.dart'; // ignore: implementation_imports
@@ -95,8 +95,12 @@ class _RecursiveVisitor extends RecursiveAstVisitor<void> {
   _RecursiveVisitor(MultiAnalysisRule rule, WorkspacePackage package)
     : _deprecatedVerifier = ElementUsageFrontierDetector(
         workspacePackage: package,
-        elementUsageSet: const DeprecatedElementUsageSet(),
-        elementUsageReporter: _DeprecatedElementUsageReporter(rule: rule),
+        usagesAndReporters: [
+          UsageSetAndReporter(
+            const DeprecatedElementUsageSet(),
+            _DeprecatedElementUsageReporter(rule: rule),
+          ),
+        ],
       );
 
   @override