Redundant constructs
- 'when' has only 'else' branch and can be simplified
Reports when expressions with only an else branch that can be simplified.
- Condition of 'if' expression is constant
Reports if expressions that have true or false constant literal condition and can be simplified.
- Constructor parameter is never used as a property
Reports primary constructor parameters that can have val or var removed.
- Null-checks can be replaced with safe-calls
Reports chained null-checks that can be replaced with safe-calls.
- Obvious explicit type
Reports local variables' explicitly given types which are obvious and thus redundant, like val f: Foo = Foo().
- Property is explicitly assigned to constructor parameter
Reports properties that are explicitly assigned to primary constructor parameters.
- Redundant '?: return null'
Reports redundant ?: return null.
- Redundant 'Companion' reference
Reports redundant Companion reference.
- Redundant 'Unit'
Reports redundant Unit expressions.
- Redundant 'Unit' return type
Reports a redundant Unit return type which can be omitted.
- Redundant 'constructor' keyword
Reports a redundant 'constructor' keyword on primary constructors.
- Redundant 'if' statement
Reports if statements which can be simplified to a single statement.
- Redundant 'inner' modifier
Reports the inner modifier on a class as redundant if it doesn't reference members of its outer class.
- Redundant 'requireNotNull' or 'checkNotNull' call
Reports redundant requireNotNull or checkNotNull call on non-nullable expressions.
- Redundant 'return' label
Reports redundant return labels outside of lambda expressions.
- Redundant 'suspend' modifier
Reports suspend modifier as redundant if no other suspending functions are called inside.
- Redundant 'with' call
Reports redundant with function calls that don't access anything from the receiver.
- Redundant SAM constructor
Reports SAM (Single Abstract Method) constructor usages which can be replaced with lambdas.
- Redundant argument-based 'let' call
Reports a redundant argument-based let call.
- Redundant backticks
Reports redundant backticks in references.
- Redundant call of conversion method
Reports redundant calls to conversion methods (for example, toString() on a String or toDouble() on a Double).
- Redundant call to 'toString()' in string template
Reports calls to toString() in string templates that can be safely removed.
- Redundant constructor body
Reports empty bodies of secondary constructors.
- Redundant creation of lambda or anonymous function
Reports lambdas or anonymous functions that are created and used immediately.
- Redundant curly braces in string template
Reports usages of curly braces in string templates around simple identifiers.
- Redundant diagnostic suppression
Reports usages of @Suppress annotations that can be safely removed because the compiler diagnostic they affect is no longer applicable in this context.
- Redundant double negation
Reports redundant double negations.
- Redundant empty primary constructor
Reports empty primary constructors when they are implicitly available anyway.
- Redundant enum constructor invocation
Reports redundant constructor invocation on an enum entry.
- Redundant explicit 'this'
Reports an explicit this when it can be omitted.
- Redundant lambda arrow
Reports redundant lambda arrows in lambdas without parameters.
- Redundant modality modifier
Reports the modality modifiers that match the default modality of an element (final for most elements, open for members with an override).
- Redundant nullable return type
Reports functions and variables with nullable return type which never return or become null.
- Redundant overriding method
Reports redundant overriding declarations.
- Redundant property getter
Reports redundant property getters.
- Redundant property setter
Reports redundant property setters.
- Redundant qualifier name
Reports redundant qualifiers (or their parts) on class names, functions, and properties.
- Redundant receiver-based 'let' call
Reports redundant receiver-based let calls.
- Redundant semicolon
Reports redundant semicolons (;) that can be safely removed.
- Redundant setter parameter type
Reports explicitly specified parameter types in property setters.
- Redundant spread operator
Reports the use of a redundant spread operator for a family of arrayOf function calls.
- Redundant string template
Reports single-expression string templates that can be safely removed.
- Redundant value argument
Reports arguments that are equal to the default values of the corresponding parameters.
- Redundant visibility modifier
Reports visibility modifiers that match the default visibility of an element (public for most elements, protected for members that override a protected member).
- Replace empty class body
Reports declarations of classes and objects with an empty body.
- Should be replaced with 'equals(..., ignoreCase = true)'
Reports case-insensitive comparisons that can be replaced with equals(..., ignoreCase = true).
- Simplifiable 'when'
Reports when expressions with the constant true or false branches.
- Unnecessary '@OptIn' annotation
Reports unnecessary opt-in annotations that can be safely removed.
- Unnecessary local variable
Reports local variables that are used only in the very next return statement or are exact copies of other variables.
- Unnecessary parentheses in function call with lambda
Reports redundant empty parentheses of function calls where the only parameter is a lambda that's outside the parentheses.
- Unnecessary supertype qualification
Reports super member calls with redundant supertype qualification.
- Unnecessary type argument
Reports function calls with type arguments that can be automatically inferred.
- Unused import directive
Reports redundant import statements.
- Unused loop index
Reports for loops iterating over a collection using the withIndex() function and not using the index variable.
- Unused receiver parameter
Reports receiver parameter of extension functions and properties that is not used.
- Unused symbol
Reports symbols that are not used or not reachable from entry points.