PreferSuperKeyRule class

Prefer super.key over Key? key with super(key: key) on Flutter widgets.

Since: v9.11.0 | Rule version: v1

Matches the Flutter framework style from Flutter 3.24 (PR #147621): forward the widget key with Dart super-parameter syntax instead of an explicit super constructor call.

Narrower than the stylistic rule prefer_super_parameters: only applies to classes that extend StatelessWidget, StatefulWidget, or a type whose name ends with Widget, and only for a Key-typed parameter named key. If you already enable prefer_super_parameters, you may get duplicate diagnostics on the same key: key forwarding; prefer one or the other for widget keys.

Detection logic lives in PreferSuperKeyDetection so the quick fix stays in lockstep with the rule.

Limitations: Only the unqualified type name Key is accepted (not import-prefix forms like widgets.Key). super(key: key) combined with other super arguments is not reported—only a sole key forward matches.

BAD:

class MyPage extends StatelessWidget {
  const MyPage({Key? key}) : super(key: key);
  // ...
}

GOOD:

class MyPage extends StatelessWidget {
  const MyPage({super.key});
  // ...
}

See: https://github.com/flutter/flutter/pull/147621

Inheritance

Constructors

PreferSuperKeyRule()

Properties

accuracyTarget → AccuracyTarget?
Optional accuracy target for this rule (for documentation and tooling). Does not enforce; used by reports and rule-audit scripts.
no setterinherited
applicableFileTypes → Set<FileType>?
The file types this rule applies to.
no setteroverride
canUseParsedResult → bool
Indicates whether this analysis rule can work with just the parsed information or if it requires a resolved unit.
no setterinherited
certIds → List<String>
CERT coding standard identifiers (e.g. STR02-C). Populate only where there is a clear mapping; leave empty for most rules initially.
no setterinherited
code → LintCode
The lint code for this rule.
no setterinherited
configAliases → List<String>
Alternate config keys that can be used to reference this rule.
no setterinherited
conflictingRules → List<String>
Curated opposite/competing rule names.
no setterinherited
cost → RuleCost
The estimated execution cost of this rule.
no setteroverride
cweIds → List<int>
CWE identifiers this rule helps prevent or detect. https://cwe.mitre.org/ — e.g. CWE-798 (Hardcoded Credentials).
no setterinherited
description → String
Short description suitable for display in console output and IDEs.
finalinherited
diagnosticCode → DiagnosticCode
The code to report for a violation.
no setterinherited
diagnosticCodes → List<DiagnosticCode>
The diagnostic codes associated with this analysis rule.
no setterinherited
documentationUrl → String
Returns the documentation URL for this rule.
no setterinherited
effectiveSeverity → DiagnosticSeverity?
Get the effective severity for this rule, considering overrides.
no setterinherited
exampleBad → String?
Short code example that VIOLATES this rule (shown in CLI walkthrough).
no setterinherited
exampleGood → String?
Short code example of COMPLIANT code (shown in CLI walkthrough).
no setterinherited
fixGenerators → List<SaropaFixGenerator>
Fix producer generators for this rule.
no setteroverride
hashCode → int
The hash code for this object.
no setterinherited
hyphenatedName → String
Returns the rule name in hyphenated format for display.
no setterinherited
impact → LintImpact
The business impact of this rule's violations.
no setteroverride
incompatibleRules → List<String>
A list of incompatible rule names.
no setterinherited
isDisabled → bool
Check if this rule is disabled via configuration.
no setterinherited
maximumLineCount → int
Maximum line count for this rule to run.
no setterinherited
minimumLineCount → int
Minimum line count for this rule to run.
no setterinherited
name → String
The rule name.
finalinherited
owasp → OwaspMapping?
OWASP categories this rule helps prevent.
no setterinherited
pubspecVisitor → PubspecVisitor?
A visitor that visits a Pubspec to perform analysis.
no setterinherited
relatedRules → List<String>
Curated "see also" rule names for discoverability in docs/IDE tooling.
no setterinherited
reporter ← DiagnosticReporter
Sets the DiagnosticReporter for the CompilationUnit currently being visited.
no getterinherited
requiredPatterns → Set<String>?
String patterns that must be present in the file for this rule to run.
no setterinherited
requiresAsync → bool
Whether this rule only applies to async code.
no setterinherited
requiresBlocImport → bool
Whether this rule only applies to files that import Bloc.
no setterinherited
requiresClassDeclaration → bool
Whether this rule only applies to files with class declarations.
no setterinherited
requiresFlutterImport → bool
Whether this rule only applies to files that import Flutter.
no setteroverride
requiresImports → bool
Whether this rule only applies to files with imports.
no setterinherited
requiresMainFunction → bool
Whether this rule only applies to files with a main() function.
no setterinherited
requiresProviderImport → bool
Whether this rule only applies to files that import Provider.
no setterinherited
requiresRiverpodImport → bool
Whether this rule only applies to files that import Riverpod.
no setterinherited
requiresWidgets → bool
Whether this rule only applies to Flutter widget code.
no setterinherited
ruleStatus → RuleStatus
Lifecycle status. Default RuleStatus.ready. Use RuleStatus.beta for new or heuristic-heavy rules; RuleStatus.deprecated for sunset.
no setterinherited
ruleType → RuleType?
Semantic type of this rule. Default null = unspecified (legacy). When set, used for quality gates, accuracy targets, and reporting.
no setteroverride
runtimeType → Type
A representation of the runtime type of the object.
no setterinherited
skipExampleFiles → bool
Whether to skip example files (example/**).
no setterinherited
skipFixtureFiles → bool
Whether to skip fixture files (fixture/, fixtures/).
no setterinherited
skipGeneratedCode → bool
Whether to skip generated files (*.g.dart, *.freezed.dart, *.gen.dart).
no setterinherited
skipTestFiles → bool
Whether to skip test files (*_test.dart, test/**).
no setterinherited
state → RuleState
The state of this analysis rule.
finalinherited
supersedesRules → List<String>
Rule names this rule supersedes/replaces.
no setterinherited
tags → Set<String>
Tags for filtering and discovery (e.g. in docs, IDE, or CI). Examples: 'performance', 'accessibility', 'suspicious', 'convention'.
no setteroverride
testRelevance → TestRelevance
How this rule relates to test files.
no setterinherited
usesTypeResolution → bool
Whether this rule triggers lazy cross-library type resolution in the analyzer (e.g. .staticType, .library, .allSupertypes, .enclosingElement).
no setterinherited

Methods

noSuchMethod(Invocation invocation) → dynamic
Invoked when a nonexistent method or property is accessed.
inherited
registerNodeProcessors(RuleVisitorRegistry registry, RuleContext context) → void
Registers node processors in the given registry.
inherited
reportAtNode(AstNode? node, {List<Object> arguments = const [], List<DiagnosticMessage>? contextMessages}) → Diagnostic?
Reports a diagnostic at node with message arguments and contextMessages.
inherited
reportAtOffset(int offset, int length, {List<Object> arguments = const [], List<DiagnosticMessage>? contextMessages}) → Diagnostic
Reports a diagnostic at offset, with length, with message arguments and contextMessages.
inherited
reportAtPubNode(PubspecNode node, {List<Object> arguments = const [], List<DiagnosticMessage> contextMessages = const []}) → Diagnostic
Reports a diagnostic at Pubspec node, with message arguments and contextMessages.
inherited
reportAtSourceRange(SourceRange sourceRange, {List<Object> arguments = const [], List<DiagnosticMessage>? contextMessages}) → Diagnostic
Reports a diagnostic at sourceRange, with message arguments and contextMessages.
inherited
reportAtToken(Token token, {List<Object> arguments = const [], List<DiagnosticMessage>? contextMessages}) → Diagnostic?
Reports a diagnostic at token, with message arguments and contextMessages.
inherited
runWithReporter(SaropaDiagnosticReporter reporter, SaropaContext context) → void
Override this method to implement your lint rule.
override
shouldSkipFile(String path) → bool
Check if a file path should be skipped based on context settings.
inherited
toString() → String
A string representation of this object.
inherited

Operators

operator ==(Object other) → bool
The equality operator.
inherited