tests/forth.rs


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use automathon::forth::{
    compiler::Compiler,
    vm::{WordList, VM},
};

fn compiler_for(text: &str) -> Compiler {
    let mut p = Compiler::new(text);
    p.compile().expect("badparse");
    p
}

fn eprintwordlist(wordlist: &WordList) {
    for i in 0..wordlist.0.len() {
        eprintln!("wordlist[{}]: {:?}", i, wordlist.0[i]);
    }
}

#[test]
fn factorial() {
    let prog = ": fac dup 1 > if dup 1 - fac * then ; 5 fac\n";
    let comp = compiler_for(prog);
    eprintwordlist(&comp.wordlist);
    let mut vm = VM::new(comp.wordlist);
    vm.run().expect("should run to completion");
    eprintln!("stack: {:?}", vm.stack);
    assert_eq!(vm.stack.0.len(), 1, "factorial result stack len");
    assert_eq!(vm.stack.0[0], 120, "factorial result value");
}