`deepest_preceding` is known to be a descendant of `node`. Repeated
calls of `Node::parent` _should_ eventually turn `deepest_preceding`
into `node`, but when the node is errored (the tree contains a syntax
error), `Node::parent` returns None.
In the typescript case:
if(true) &&true
// ^ press enter here
The tree is:
(program [0, 0] - [1, 0]
(if_statement [0, 0] - [0, 15]
condition: (parenthesized_expression [0, 2] - [0, 8]
(true [0, 3] - [0, 7]))
consequence: (expression_statement [0, 8] - [0, 15]
(binary_expression [0, 8] - [0, 15]
left: (identifier [0, 8] - [0, 8])
right: (true [0, 11] - [0, 15])))))
`node` is the `program` node and `deepest_preceding` is the
`binary_expression`. The tree is errored on the `binary_expression`
node with `(MISSING identifier [0, 8] - [0, 8])`.
In the C++ case:
; <<
// press enter after the ';'
The tree is:
(translation_unit [0, 0] - [1, 0]
(expression_statement [0, 0] - [0, 1])
(ERROR [0, 1] - [0, 4]
(identifier [0, 1] - [0, 1])))
`node` is the `translation_unit` and `deepest_preceding` is the `ERROR`
node.
In both cases, `Node::parent` on the errored node returns None.
3e84434c69