syntax_data: {"ast_node_type":"other","tokens":[{"end":64,"kind":"keyword","start":0,"text":"//"}]}
source_snippet:     // stops after it finds a node that has a next-sibling node.
context_before:     // Each loop run emits a slice - it starts by find a "childless" unvisited node, backtracking upwards, and it
context_after:     // This next-sibling node will used as the starting point of next slice.