SOURCE_FILE
  FN
    FN_KW "fn"
    WHITESPACE " "
    NAME
      IDENT "foo"
    PARAM_LIST
      L_PAREN "("
      R_PAREN ")"
    WHITESPACE " "
    BLOCK_EXPR
      STMT_LIST
        L_CURLY "{"
        WHITESPACE "\n    "
        MATCH_EXPR
          MATCH_KW "match"
          WHITESPACE " "
          TUPLE_EXPR
            L_PAREN "("
            R_PAREN ")"
          WHITESPACE " "
          MATCH_ARM_LIST
            L_CURLY "{"
            WHITESPACE "\n        "
            MATCH_ARM
              ATTR
                POUND "#"
                L_BRACK "["
                META
                  PATH
                    PATH_SEGMENT
                      NAME_REF
                        IDENT "cfg"
                  TOKEN_TREE
                    L_PAREN "("
                    IDENT "feature"
                    WHITESPACE " "
                    EQ "="
                    WHITESPACE " "
                    STRING "\"some\""
                    R_PAREN ")"
                R_BRACK "]"
              WHITESPACE "\n        "
              WILDCARD_PAT
                UNDERSCORE "_"
              WHITESPACE " "
              FAT_ARROW "=>"
              WHITESPACE " "
              TUPLE_EXPR
                L_PAREN "("
                R_PAREN ")"
              COMMA ","
            WHITESPACE "\n        "
            MATCH_ARM
              ATTR
                POUND "#"
                L_BRACK "["
                META
                  PATH
                    PATH_SEGMENT
                      NAME_REF
                        IDENT "cfg"
                  TOKEN_TREE
                    L_PAREN "("
                    IDENT "feature"
                    WHITESPACE " "
                    EQ "="
                    WHITESPACE " "
                    STRING "\"other\""
                    R_PAREN ")"
                R_BRACK "]"
              WHITESPACE "\n        "
              WILDCARD_PAT
                UNDERSCORE "_"
              WHITESPACE " "
              FAT_ARROW "=>"
              WHITESPACE " "
              TUPLE_EXPR
                L_PAREN "("
                R_PAREN ")"
              COMMA ","
            WHITESPACE "\n        "
            MATCH_ARM
              ATTR
                POUND "#"
                L_BRACK "["
                META
                  PATH
                    PATH_SEGMENT
                      NAME_REF
                        IDENT "cfg"
                  TOKEN_TREE
                    L_PAREN "("
                    IDENT "feature"
                    WHITESPACE " "
                    EQ "="
                    WHITESPACE " "
                    STRING "\"many\""
                    R_PAREN ")"
                R_BRACK "]"
              WHITESPACE "\n        "
              ATTR
                POUND "#"
                L_BRACK "["
                META
                  PATH
                    PATH_SEGMENT
                      NAME_REF
                        IDENT "cfg"
                  TOKEN_TREE
                    L_PAREN "("
                    IDENT "feature"
                    WHITESPACE " "
                    EQ "="
                    WHITESPACE " "
                    STRING "\"attributes\""
                    R_PAREN ")"
                R_BRACK "]"
              WHITESPACE "\n        "
              ATTR
                POUND "#"
                L_BRACK "["
                META
                  PATH
                    PATH_SEGMENT
                      NAME_REF
                        IDENT "cfg"
                  TOKEN_TREE
                    L_PAREN "("
                    IDENT "feature"
                    WHITESPACE " "
                    EQ "="
                    WHITESPACE " "
                    STRING "\"before\""
                    R_PAREN ")"
                R_BRACK "]"
              WHITESPACE "\n        "
              WILDCARD_PAT
                UNDERSCORE "_"
              WHITESPACE " "
              FAT_ARROW "=>"
              WHITESPACE " "
              TUPLE_EXPR
                L_PAREN "("
                R_PAREN ")"
              COMMA ","
            WHITESPACE "\n    "
            R_CURLY "}"
        WHITESPACE "\n"
        R_CURLY "}"
  WHITESPACE "\n"
