DuplicateFunction.ql

/**
 * @name Duplicate function
 * @description There is another identical implementation of this function. Extract the code to a common file or superclass or delegate to improve sharing.
 * @kind problem
 * @id cpp/duplicate-function
 * @problem.severity recommendation
 * @precision medium
 * @tags testability
 *       maintainability
 *       duplicate-code
 *       non-attributable
 */
import cpp
import CodeDuplication

predicate relevant(FunctionDeclarationEntry m) {
  exists(Location loc |
    loc = m.getBlock().getLocation() and
    (
      loc.getStartLine() + 5 < loc.getEndLine() and not m.getName().matches("get%")
      or
      loc.getStartLine() + 10 < loc.getEndLine()
    )
  )
}

from FunctionDeclarationEntry m, FunctionDeclarationEntry other
where duplicateMethod(m, other)
  and relevant(m)
  and not m.getFunction().isConstructedFrom(_)
  and not other.getFunction().isConstructedFrom(_)
  and not fileLevelDuplication(m.getFile(), other.getFile())
  and not classLevelDuplication(m.getFunction().getDeclaringType(), other.getFunction().getDeclaringType())
select m, "Function " + m.getName() + " is duplicated at $@.",
   other,
   other.getFile().getBaseName() + ":" + other.getLocation().getStartLine().toString()