ALWAYS_DECLARE_RETURN_TYPES
Code style
High
Method should have return type
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Dart rules
Codiga provides multiple set of rules for 12+ languages. Below we provide a link and a description for all the rules supported by our platform. Note that not all the rules are being listed and described below.
always_specify_types
Code style
Minor
Always specify types
ARGUMENT_TYPE_NOT_ASSIGNABLE
Code style
Medium
Invalid assignments
ASSET_DOES_NOT_EXIST
Code style
Medium
Asset does not exists
AVOID_BOOL_LITERALS_IN_CONDITIONAL_EXPRESSIONS
Code style
Minor
Avoid bool literals in condition
AVOID_CLASSES_WITH_ONLY_STATIC_MEMBERS
Code style
Minor
Avoid defining a class that contains only static members.
AVOID_ESCAPING_INNER_QUOTES
Code style
Minor
Avoid escaping inner quotes by converting surrounding quotes.
AVOID_FUNCTION_LITERALS_IN_FOREACH_CALLS
Code style
Minor
Avoid using `forEach` with a function literal.
avoid_init_to_null
Code style
Minor
Don't explicitly initialize variables to null.
AVOID_POSITIONAL_BOOLEAN_PARAMETERS
Code style
Minor
Avoid positional boolean parameters.
AVOID_PRINT
Code style
High
Avoid `print` calls in production code.
AVOID_REDUNDANT_ARGUMENT_VALUES
Code style
Minor
Avoid redundant argument values.
AVOID_RETURN_TYPES_ON_SETTERS
Code style
Minor
Avoid return types on setters.
AVOID_UNNECESSARY_CONTAINERS
Code style
Minor
Avoid unnecessary containers.
AVOID_VOID_ASYNC
Code style
Minor
Avoid async functions that return void.
AVOID_WEB_LIBRARIES_IN_FLUTTER
Code style
Minor
Avoid using web-only libraries outside Flutter web plugin packages.
AWAIT_ONLY_FUTURES
Code style
Minor
await' should only apply to futures
BODY_MIGHT_COMPLETE_NORMALLY
Code style
Medium
The body might complete normally
CAMEL_CASE_TYPES
Code style
Minor
Name types using UpperCamelCase.
CAST_NULLABLE_TO_NON_NULLABLE
Code style
Minor
Don't cast a nullable value to a non nullable type.
CAST_TO_NON_TYPE
Code style
Medium
The name isn't a type
close_sinks
Code style
Minor
Close instances of `dart.core.Sink`.\n
CONST_INITIALIZED_WITH_NON_CONSTANT_VALUE
Code style
Medium
Const variables must be initialized with a constant value.
CONST_WITH_NON_CONSTANT_ARGUMENT
Code style
Medium
Arguments of a constant creation must be constant expressions.
COULD_NOT_INFER
Code style
Medium
Cannot infer type
CREATION_WITH_NON_TYPE
Code style
Medium
The name 'BubbleStyle' isn't a class.\n
DEAD_CODE
Code style
Minor
Dead code.
DEAD_CODE_ON_CATCH_SUBTYPE
Code style
Minor
Dead code on catch subtype.
DEAD_NULL_AWARE_EXPRESSION
Code style
Minor
The left operand can't be null.
DEFAULT_LIST_CONSTRUCTOR
Code style
Medium
The default 'List' constructor isn't available when null safety is enabled.
DEPEND_ON_REFERENCED_PACKAGES
Code style
Minor
Depend on referenced packages.
DEPRECATED_MEMBER_USE
Code style
Minor
Member is deprecated and shouldn't be used. This property is no longer used
DIRECTIVES_ORDERING
Code style
Minor
Import ordering
DUPLICATE_IMPORT
Code style
Minor
Duplicate import.
EMPTY_CATCHES
Code style
Minor
Avoid empty catch blocks.
empty_constructor_bodies
Code style
Minor
Use `;` instead of `{}` for empty constructor bodies.
empty_statements
Code style
Minor
Detect empty statements (dead code)
EOL_AT_END_OF_FILE
Code style
Minor
Put a single newline at end of file.
EXPECTED_TOKEN
Code style
Medium
Expected to find '['.
EXTENDS_NON_CLASS
Code style
Medium
Classes can only extend other classes.
EXTRA_POSITIONAL_ARGUMENTS
Code style
Medium
Too many positional arguments.
FILE_NAMES
Code style
Minor
Name source files using `lowercase\_with\_underscores`.
GETTER_NOT_SUBTYPE_SETTER_TYPES
Code style
Medium
Invalid return type
HASH_AND_EQUALS
Code style
Minor
Override `hashCode` if overriding `==`
ILLEGAL_ASSIGNMENT_TO_NON_ASSIGNABLE
Code style
High
Illegal assignment to non-assignable expression.
implementation_imports
Code style
Minor
Don't import implementation files from another package.
IMPLEMENTS_NON_CLASS
Code style
Medium
Classes and mixins can only implement other classes and mixins.
IMPORT_OF_LEGACY_LIBRARY_INTO_NULL_SAFE
Code style
Minor
Legacy library
INCLUDE_FILE_NOT_FOUND
Code style
Medium
Include file not found
INVALID_ANNOTATION_TARGET
Code style
Minor
Invalid annotation target
INVALID_ASSIGNMENT
Code style
Medium
Invalid assignments
INVALID_CONSTANT
Code style
Medium
Invalid constant value
INVALID_NULL_AWARE_OPERATOR
Code style
Minor
The receiver can't be null because of short-circuiting
INVALID_OVERRIDE
Code style
Medium
Invalid override
INVALID_USE_OF_PROTECTED_MEMBER
Code style
Minor
Invalid use of protected members
INVARIANT_BOOLEANS
Code style
Minor
Conditions should not unconditionally evaluate to `true` or to `false`.
JOIN_RETURN_WITH_ASSIGNMENT
Code style
Minor
Join return statement with assignment when possible.
LIBRARY_PREFIXES
Code style
Minor
Use `lowercase\_with\_underscores` when specifying a library prefix.
LIST_ELEMENT_TYPE_NOT_ASSIGNABLE
Code style
Medium
List element type not assignable
MISSING_ASSIGNABLE_SELECTOR
Code style
High
Missing selector
MISSING_DEFAULT_VALUE_FOR_PARAMETER
Code style
Medium
Missing default value for parameter
MISSING_ENUM_CONSTANT_IN_SWITCH
Code style
Minor
Missing case clause for 'null'.
MISSING_IDENTIFIER
Code style
Medium
Expected an identifier.
MISSING_REQUIRED_ARGUMENT
Code style
High
Missing required argument
MISSING_REQUIRED_PARAM
Code style
Medium
Missing required parameters
MISSING_RETURN
Code style
Minor
Missing return value
MIXIN_OF_NON_CLASS
Code style
Medium
Classes can only mix in mixins and classes.
MIXIN_WITH_NON_CLASS_SUPERCLASS
Code style
Medium
Mixin can only be applied to class.
MUST_BE_IMMUTABLE
Code style
Minor
Must be immutable
MUST_CALL_SUPER
Code style
Minor
This method overrides a method annotated as '@mustCallSuper' in 'State'
NEW_WITH_UNDEFINED_CONSTRUCTOR_DEFAULT
Code style
Medium
The class doesn't have a default constructor.
NO_DEFAULT_SUPER_CONSTRUCTOR
Code style
High
No default super constructor
NON_ABSTRACT_CLASS_INHERITS_ABSTRACT_MEMBER
Code style
Medium
Missing concrete implementations of methods
NON_BOOL_CONDITION
Code style
Medium
Conditions must have a static type of 'bool'
NON_CONSTANT_CASE_EXPRESSION
Code style
Medium
Case expressions must be constant
NON_CONSTANT_DEFAULT_VALUE
Code style
Medium
The default value of an optional parameter must be constant
non_constant_identifier_names
Code style
Minor
Name non-constant identifiers using lowerCamelCase
NON_CONSTANT_LIST_ELEMENT
Code style
Medium
The values in a const list literal must be constants
NON_CONSTANT_MAP_VALUE
Code style
Medium
The values in a const map literal must be constant
NON_TYPE_AS_TYPE_ARGUMENT
Code style
Medium
The name isn't a type so it can't be used as a type argument
NON_TYPE_IN_CATCH_CLAUSE
Code style
Medium
The name isn't a type and can't be used in an on-catch clause.
NOOP_PRIMITIVE_OPERATIONS
Code style
Minor
Noop primitive operations.
NOT_ASSIGNED_POTENTIALLY_NON_NULLABLE_LOCAL_VARIABLE
Code style
Medium
The non-nullable local variable must be assigned before it can be used.
NOT_INITIALIZED_NON_NULLABLE_INSTANCE_FIELD
Code style
Medium
Non-nullable instance field must be initialized.
NOT_INITIALIZED_NON_NULLABLE_VARIABLE
Code style
Medium
The non-nullable variable must be initialized.
NULLABLE_TYPE_IN_CATCH_CLAUSE
Code style
Minor
A potentially nullable type can't be used in an 'on' clause because it isn't valid to throw a nullable expression.
OVERRIDDEN_FIELDS
Code style
Minor
Don't override fields.
OVERRIDE_ON_NON_OVERRIDING_MEMBER
Code style
Minor
The field doesn't override an inherited getter or setter.
POSITIONAL_AFTER_NAMED_ARGUMENT
Code style
Medium
Positional arguments must occur before named arguments.
PREFER_CONST_CONSTRUCTORS
Code style
Minor
Prefer const with constant constructors.
PREFER_CONST_CONSTRUCTORS_IN_IMMUTABLES
Code style
Minor
Prefer declaring const constructors on `@immutable` classes
PREFER_CONST_DECLARATIONS
Code style
High
Prefer const over final for declarations
PREFER_CONST_LITERALS_TO_CREATE_IMMUTABLES
Code style
Minor
Prefer const literals as parameters of constructors on @immutable classes.
PREFER_FINAL_IN_FOR_EACH
Code style
Minor
Prefer final in for-each loop variable if reference is not reassigned.
PREFER_FINAL_LOCALS
Code style
High
Prefer final for variable declarations if they are not reassigned.
PREFER_IF_ELEMENTS_TO_CONDITIONAL_EXPRESSIONS
Code style
Minor
Prefer if elements to conditional expressions where possible.
PREFER_IF_NULL_OPERATORS
Code style
Minor
Prefer using if null operators.
PREFER_INITIALIZING_FORMALS
Code style
Minor
Use initializing formals when possible.
PREFER_INTERPOLATION_TO_COMPOSE_STRINGS
Code style
Minor
Use interpolation to compose strings and values.
PREFER_IS_EMPTY
Code style
Minor
Use isEmpty instead of length\n
PREFER_IS_NOT_EMPTY
Code style
Minor
Use `isNotEmpty` for Iterables and Maps.
PREFER_NULL_AWARE_METHOD_CALLS
Code style
Minor
Prefer null aware method calls.
PREFER_TYPING_UNINITIALIZED_VARIABLES
Code style
Minor
Prefer typing uninitialized variables and fields.
REDIRECT_TO_NON_CLASS
Code style
High
Name isn't a type and can't be used in a redirected constructor.
REQUIRE_TRAILING_COMMAS
Code style
Minor
Missing a required trailing comma.
RETURN_OF_INVALID_TYPE
Code style
Medium
Invalid return type
RETURN_OF_INVALID_TYPE_FROM_CLOSURE
Code style
Medium
Invalid return type from closure
SIZED_BOX_FOR_WHITESPACE
Code style
Minor
SizedBox for whitespace.
SORT_CHILD_PROPERTIES_LAST
Code style
High
Sort child properties last in widget instance creations.
SORT_PUB_DEPENDENCIES
Code style
Minor
Sort pub dependencies.
TYPE_ANNOTATE_PUBLIC_APIS
Code style
High
Type annotate public APIs.
TYPE_ARGUMENT_NOT_MATCHING_BOUNDS
Code style
High
Type arguments do not match bounds
TYPE_TEST_WITH_UNDEFINED_NAME
Code style
Medium
Undefined name
UNCHECKED_USE_OF_NULLABLE_VALUE
Code style
Medium
Method can't be unconditionally invoked because the receiver can be 'null'.
UNDEFINED_CONSTRUCTOR_IN_INITIALIZER
Code style
Medium
Undefined constructor
UNDEFINED_GETTER
Code style
Medium
Undefined getter
UNDEFINED_NAMED_PARAMETER
Code style
Medium
Named parameter undefined
UNDEFINED_OPERATOR
Code style
High
Undefined operator
UNDEFINED_SETTER
Code style
Medium
Undefined setter
UNDEFINED_SUPER_MEMBER
Code style
Medium
Undefined super member
unnecessary_brace_in_string_interps
Code style
Minor
Avoid using braces in interpolation when not needed.
UNNECESSARY_CAST
Code style
Minor
Unnecessary cast.
UNNECESSARY_NEW
Code style
Minor
Unnecessary new keyword.
UNNECESSARY_NON_NULL_ASSERTION
Code style
Medium
Uneccessary non null assertion
UNNECESSARY_NULL_CHECKS
Code style
Minor
Unnecessary null checks
UNNECESSARY_NULL_COMPARISON
Code style
Minor
The operand can't be null
UNNECESSARY_PARENTHESIS
Code style
Minor
Unnecessary parenthesis
unnecessary_statements
Code style
Minor
Avoid using unnecessary statements
UNNECESSARY_STRING_INTERPOLATIONS
Code style
Minor
Unnecessary string interpolation
UNNECESSARY_THIS
Code style
High
Unecessary this
UNSUPPORTED_OPERATOR
Code style
High
The '===' operator is not supported
UNUSED_CATCH_CLAUSE
Code style
Minor
Unused catch clause
UNUSED_CATCH_STACK
Code style
Minor
Stack trace not used
UNUSED_ELEMENT
Code style
Minor
Unused element
UNUSED_FIELD
Code style
Minor
Unused fiel
UNUSED_IMPORT
Code style
Minor
Unused import
UNUSED_LABEL
Code style
Minor
Unused label
UNUSED_LOCAL_VARIABLE
Code style
Minor
Unused local variable
URI_HAS_NOT_BEEN_GENERATED
Code style
Medium
URI has not been generated
USE_BUILD_CONTEXT_SYNCHRONOUSLY
Code style
Minor
Use build context synchronuously
USE_LATE_FOR_PRIVATE_FIELDS_AND_VARIABLES
Code style
Minor
Use late for private members with non-nullable type.
USE_NAMED_CONSTANTS
Code style
Minor
Use named constants
USE_OF_VOID_RESULT
Code style
High
Use of void results
USE_STRING_BUFFERS
Code style
Minor
Use string buffers to compose strings
ALWAYS_USE_PACKAGE_IMPORTS
Best practice
High
Avoid relative imports.
ANNOTATE_OVERRIDES
Best practice
Medium
Annotate overridden members.
AVOID_DYNAMIC_CALLS
Best practice
High
Avoid method calls or property accesses on a "dynamic" target
https://dart-lang.github.io/linter/lints/avoid_returning_null_for_void.html
Best practice
Critical
Avoid returning null for void
AVOID_RETURNING_NULL_FOR_VOID
Safety
High
Avoid returning null for void
CONST_CONSTRUCTOR_PARAM_TYPE_MISMATCH
Error prone
Medium
Type mismatch in constructor parameter
CONST_EVAL_THROWS_EXCEPTION
Best practice
High
Eval throws exception.
LEADING_NEWLINES_IN_MULTILINE_STRINGS
Best practice
Medium
Start multiline strings with a newline.
UNNECESSARY_IMPORT
Best practice
Minor
Unnecessary import
NOT_ENOUGH_POSITIONAL_ARGUMENTS
Error prone
High
Incorrect number of arguments passed to function call
UNNECESSARY_TYPE_CHECK
Best practice
Medium
Unnecessary type check
BODY_MIGHT_COMPLETE_NORMALLY_NULLABLE
Best practice
Medium
The analyzer produces this diagnostic when a method or function can implicitly return null by falling off the end. While this is valid Dart code, it’s better for the return of null to be explicit.
UNNECESSARY_DEV_DEPENDENCY
Error prone
Medium
The dev dependency is unnecessary because there is also a normal dependency on that package.
NULL_ARGUMENT_TO_NON_NULL_TYPE
Safety
High
Function/method shouldn’t be called with a null argument for the non-nullable type argument.
UNNECESSARY_QUESTION_MARK
Best practice
Medium
The ‘?’ is unnecessary because the value is nullable without it.
DUPLICATE_NAMED_ARGUMENT
Error prone
High
The argument was already specified.
NO_LEADING_UNDERSCORES_FOR_LOCAL_IDENTIFIERS
Code style
Medium
Avoid leading underscores for local identifiers.
PREFER_FINAL_FIELDS
Best practice
Medium
Field could be final.
PREFER_GENERIC_FUNCTION_TYPE_ALIASES
Best practice
Medium
Prefer generic function type aliases.
VARIABLE_TYPE_MISMATCH
Error prone
Critical
Type mismatch in assignment
AVOID_IMPLEMENTING_VALUE_TYPES
Best practice
Medium
Don't implement classes that override `==`.
AVOID_SETTERS_WITHOUT_GETTERS
Design
Medium
Avoid setters without getters.
CONSTANT_IDENTIFIER_NAMES
Code style
Medium
Prefer using lowerCamelCase for constant names.
UNNECESSARY_OVERRIDES
Best practice
Medium
Don't override a method to do a super method invocation with the same parameters.
DUPLICATE_DEFINITION
Error prone
Medium
Name already defined.
DIRECTIVE_AFTER_DECLARATION
Code style
Minor
Directives must appear before any declarations.
DUPLICATE_PART
Best practice
Medium
The library already contains a part.
EXTRA_POSITIONAL_ARGUMENTS_COULD_BE_NAMED
Error prone
Medium
Too many positional arguments.
FLUTTER_STYLE_TODOS
Code style
Minor
Use Flutter TODO format.
NO_LEADING_UNDERSCORES_FOR_LIBRARY_PREFIXES
Code style
Minor
Avoid leading underscores for library prefixes.
INVALID_FACTORY_NAME_NOT_A_CLASS
Code style
Minor
The name of a factory constructor must be the same as the name of the immediately enclosing class.
INVALID_LANGUAGE_VERSION_OVERRIDE
Best practice
Medium
The language version override must be specified before any declaration or directive.
INSTANCE_ACCESS_TO_STATIC_MEMBER
Error prone
High
Static method can't be accessed through an instance.
INVALID_RETURN_TYPE_FOR_CATCH_ERROR
Design
High
Invalid return type value
LIBRARY_PRIVATE_TYPES_IN_PUBLIC_API
Design
High
Using library private types in public APIs
UNRELATED_TYPE_EQUALITY_CHECKS
Error prone
High
Equality operator `==` invocation with references of unrelated types
USE_KEY_IN_WIDGET_CONSTRUCTORS
Best practice
High
Use key in widget constructors.
PREFER_VOID_TO_NULL
Safety
High
Don't use the Null type, unless you are positive that you don't want void.
DUPLICATE_IGNORE
Error prone
Medium
Diagnostic doesn't need to be ignored here because it's already being ignored
ASSET_DIRECTORY_DOES_NOT_EXIST
Error prone
Medium
The asset directory doesn't exist.
CONST_WITH_NON_CONST
Error prone
Medium
The constructor being called isn't a const constructor.
NOT_A_TYPE
Error prone
High
Mentioned type is not a type
MUST_BE_A_NATIVE_FUNCTION_TYPE
Best practice
Medium
Type given must be a valid native function type
NON_CONSTANT_TYPE_ARGUMENT
Best practice
Medium
The type arguments to must be known at compile time, so they can’t be type parameters
SUBTYPE_OF_DISALLOWED_TYPE
Best practice
Medium
Type can’t be used as a superclass constraint.