/**
 * @name Unused parameter
 * @description Parameter is defined but not used
 * @kind problem
 * @tags maintainability
 * @problem.severity recommendation
 * @sub-severity high
 * @precision medium
 * @id py/unused-parameter
 */

import python
import Definition

predicate unused_parameter(FunctionValue f, LocalVariable v) {
  v.isParameter() and
  v.getScope() = f.getScope() and
  not name_acceptable_for_unused_variable(v) and
  not exists(NameNode u | u.uses(v)) and
  not exists(Name inner, LocalVariable iv |
    inner.uses(iv) and iv.getId() = v.getId() and inner.getScope().getScope() = v.getScope()
  )
}

predicate is_abstract(FunctionValue func) {
  func.getScope().getADecorator().(Name).getId().matches("%abstract%")
}

from PythonFunctionValue f, LocalVariable v
where
  v.getId() != "self" and
  unused_parameter(f, v) and
  not f.isOverridingMethod() and
  not f.isOverriddenMethod() and
  not is_abstract(f)
select f, "The parameter '" + v.getId() + "' is never used."