Fix condition for breaking loop on EPSILON check

Author: MammarDr

src/sets-generator.js

@@ -120,7 +120,7 @@ export default class SetsGenerator {
       // And if there was no EPSILON, we're done (otherwise, we
       // don't break the loop, and proceed to the next symbol of the RHS.
       if (
-        !firstOfCurrent.hasOwnProperty(EPSILON) ||
+        !firstOfCurrent.hasOwnProperty(EPSILON) &&
         (nonTerminal && !nonTerminal.hasDirectEpsilon)
       ) {
         break;