class Prism::CaseNode

def ===(other)

comparing the value of locations. Locations are checked only for presence.
Implements case-equality for the node. This is effectively == but without 
def ===(other)
  other.is_a?(CaseNode) &&
    (predicate === other.predicate) &&
    (conditions.length == other.conditions.length) &&
    conditions.zip(other.conditions).all? { |left, right| left === right } &&
    (else_clause === other.else_clause) &&
    (case_keyword_loc.nil? == other.case_keyword_loc.nil?) &&
    (end_keyword_loc.nil? == other.end_keyword_loc.nil?)
end