@ ProgramNode (location: (1,0)-(3,19))
├── locals: []
└── statements:
    @ StatementsNode (location: (1,0)-(3,19))
    └── body: (length: 2)
        ├── @ UntilNode (location: (1,0)-(1,21))
        │   ├── keyword_loc: (1,0)-(1,5) = "until"
        │   ├── closing_loc: (1,18)-(1,21) = "end"
        │   ├── predicate:
        │   │   @ CallNode (location: (1,6)-(1,9))
        │   │   ├── receiver: ∅
        │   │   ├── call_operator_loc: ∅
        │   │   ├── message_loc: (1,6)-(1,9) = "foo"
        │   │   ├── opening_loc: ∅
        │   │   ├── arguments: ∅
        │   │   ├── closing_loc: ∅
        │   │   ├── block: ∅
        │   │   ├── flags: variable_call
        │   │   └── name: :foo
        │   ├── statements:
        │   │   @ StatementsNode (location: (1,13)-(1,17))
        │   │   └── body: (length: 1)
        │   │       └── @ CallNode (location: (1,13)-(1,17))
        │   │           ├── receiver: ∅
        │   │           ├── call_operator_loc: ∅
        │   │           ├── message_loc: (1,13)-(1,17) = "meth"
        │   │           ├── opening_loc: ∅
        │   │           ├── arguments: ∅
        │   │           ├── closing_loc: ∅
        │   │           ├── block: ∅
        │   │           ├── flags: variable_call
        │   │           └── name: :meth
        │   └── flags: ∅
        └── @ UntilNode (location: (3,0)-(3,19))
            ├── keyword_loc: (3,0)-(3,5) = "until"
            ├── closing_loc: (3,16)-(3,19) = "end"
            ├── predicate:
            │   @ CallNode (location: (3,6)-(3,9))
            │   ├── receiver: ∅
            │   ├── call_operator_loc: ∅
            │   ├── message_loc: (3,6)-(3,9) = "foo"
            │   ├── opening_loc: ∅
            │   ├── arguments: ∅
            │   ├── closing_loc: ∅
            │   ├── block: ∅
            │   ├── flags: variable_call
            │   └── name: :foo
            ├── statements:
            │   @ StatementsNode (location: (3,11)-(3,15))
            │   └── body: (length: 1)
            │       └── @ CallNode (location: (3,11)-(3,15))
            │           ├── receiver: ∅
            │           ├── call_operator_loc: ∅
            │           ├── message_loc: (3,11)-(3,15) = "meth"
            │           ├── opening_loc: ∅
            │           ├── arguments: ∅
            │           ├── closing_loc: ∅
            │           ├── block: ∅
            │           ├── flags: variable_call
            │           └── name: :meth
            └── flags: ∅
