Scalactic's === will consistently either allow or not allow both A === B and B === A

gistfile1.scala

scala> import CheckedEquality._
import CheckedEquality._

scala> 1 === "one"
<console>:20: error: types Int and String do not adhere to the type constraint selected for the === and !== operators; the missing implicit parameter is of type org.scalactic.EqualityConstraint[Int,String]
              1 === "one"
                ^

scala> "one" === 1
<console>:20: error: types String and Int do not adhere to the type constraint selected for the === and !== operators; the missing implicit parameter is of type org.scalactic.EqualityConstraint[String,Int]
              "one" === 1
                    ^

scala> 1 === 1L
res2: Boolean = true

scala> 1L === 1
res3: Boolean = true

scala> import StrictCheckedEquality._
import StrictCheckedEquality._

scala> 1 === "one"
<console>:23: error: types Int and String do not adhere to the type constraint selected for the === and !== operators; the missing implicit parameter is of type org.scalactic.EqualityConstraint[Int,String]
              1 === "one"
                ^

scala> "one" === 1
<console>:23: error: types String and Int do not adhere to the type constraint selected for the === and !== operators; the missing implicit parameter is of type org.scalactic.EqualityConstraint[String,Int]
              "one" === 1
                    ^

scala> 1 === 1L
<console>:23: error: types Int and Long do not adhere to the type constraint selected for the === and !== operators; the missing implicit parameter is of type org.scalactic.EqualityConstraint[Int,Long]
              1 === 1L
                ^

scala> 1L === 1
<console>:23: error: types Long and Int do not adhere to the type constraint selected for the === and !== operators; the missing implicit parameter is of type org.scalactic.EqualityConstraint[Long,Int]
              1L === 1
                 ^