perses

Sophisticated reducers like C-Reduce do know things like that parens go in pairs. C-Reduce has many transformation operations, and while some are syntax agnostic (delete a few characters or tokens), others use Clang to try to parse the input as C++ and transform the AST. Perses is a reducer that works on an AST and claims to only try syntactically valid candidate inputs. It also claims to be language agnostic, and I don't know how these two things go together. But it does work nicely for Java for me. https://github.com/uw-pluverse/perses / https://faculty.cc.gatech.edu/~qzhang414/papers/icse18_cheng...