@ ProgramNode (location: (1,0)-(1,14))
├── locals: []
└── statements:
    @ StatementsNode (location: (1,0)-(1,14))
    └── body: (length: 1)
        └── @ UntilNode (location: (1,0)-(1,14))
            ├── keyword_loc: (1,5)-(1,10) = "until"
            ├── closing_loc: ∅
            ├── predicate:
            │   @ CallNode (location: (1,11)-(1,14))
            │   ├── receiver: ∅
            │   ├── call_operator_loc: ∅
            │   ├── message_loc: (1,11)-(1,14) = "foo"
            │   ├── opening_loc: ∅
            │   ├── arguments: ∅
            │   ├── closing_loc: ∅
            │   ├── block: ∅
            │   ├── flags: variable_call
            │   └── name: :foo
            ├── statements:
            │   @ StatementsNode (location: (1,0)-(1,4))
            │   └── body: (length: 1)
            │       └── @ CallNode (location: (1,0)-(1,4))
            │           ├── receiver: ∅
            │           ├── call_operator_loc: ∅
            │           ├── message_loc: (1,0)-(1,4) = "meth"
            │           ├── opening_loc: ∅
            │           ├── arguments: ∅
            │           ├── closing_loc: ∅
            │           ├── block: ∅
            │           ├── flags: variable_call
            │           └── name: :meth
            └── flags: ∅
