@ ProgramNode (location: (1,0)-(1,33))
├── flags: ∅
├── locals: []
└── statements:
    @ StatementsNode (location: (1,0)-(1,33))
    ├── flags: ∅
    └── body: (length: 1)
        └── @ CaseMatchNode (location: (1,0)-(1,33))
            ├── flags: newline
            ├── predicate:
            │   @ CallNode (location: (1,5)-(1,8))
            │   ├── flags: variable_call, ignore_visibility
            │   ├── receiver: ∅
            │   ├── call_operator_loc: ∅
            │   ├── name: :foo
            │   ├── message_loc: (1,5)-(1,8) = "foo"
            │   ├── opening_loc: ∅
            │   ├── arguments: ∅
            │   ├── closing_loc: ∅
            │   ├── equal_loc: ∅
            │   └── block: ∅
            ├── conditions: (length: 1)
            │   └── @ InNode (location: (1,10)-(1,28))
            │       ├── flags: ∅
            │       ├── pattern:
            │       │   @ HashPatternNode (location: (1,13)-(1,18))
            │       │   ├── flags: ∅
            │       │   ├── constant: ∅
            │       │   ├── elements: (length: 0)
            │       │   ├── rest:
            │       │   │   @ NoKeywordsParameterNode (location: (1,13)-(1,18))
            │       │   │   ├── flags: ∅
            │       │   │   ├── operator_loc: (1,13)-(1,15) = "**"
            │       │   │   └── keyword_loc: (1,15)-(1,18) = "nil"
            │       │   ├── opening_loc: ∅
            │       │   └── closing_loc: ∅
            │       ├── statements:
            │       │   @ StatementsNode (location: (1,24)-(1,28))
            │       │   ├── flags: ∅
            │       │   └── body: (length: 1)
            │       │       └── @ TrueNode (location: (1,24)-(1,28))
            │       │           └── flags: newline, static_literal
            │       ├── in_loc: (1,10)-(1,12) = "in"
            │       └── then_loc: (1,19)-(1,23) = "then"
            ├── else_clause: ∅
            ├── case_keyword_loc: (1,0)-(1,4) = "case"
            └── end_keyword_loc: (1,30)-(1,33) = "end"
