The migration to antlr4 should not be an issue, we are not having a big change in antlr.
I checked the java generation for antlr2, and I could not find change we made there.
To test this, we just need to use Antlr4 to generate the lexer and parser from the two .g files in the oal.als project
My exceptation we will have same output
If that happens, that means the only change in antlr is the SQL conversion (parsing the AST to generate SQL instead of Java)
I know this while ago, but I could not test it out. So I thought to say it, until I do