This commit also marks `child_containing_descendant()` as deprecated
(per upstream's documentation), and uses `child_with_descendant()` in
its place. Minimum required tree-sitter version will now be `0.24`.
Problem:
Tests have lots of exec_lua calls which input blocks of code
provided as unformatted strings.
Solution:
Teach exec_lua how to handle functions.
Problem: `has-ancestor?` is O(n²) for the depth of the tree since it iterates over each of the node's ancestors (bottom-up), and each ancestor takes O(n) time.
This happens because tree-sitter's nodes don't store their parent nodes, and the tree is searched (top-down) each time a new parent is requested.
Solution: Make use of new `ts_node_child_containing_descendant()` in tree-sitter v0.22.6 (which is now the minimum required version) to rewrite the `has-ancestor?` predicate in C to become O(n).
For a sample file, decreases the time taken by `has-ancestor?` from 360ms to 6ms.
Specifically, functions that are run in the context of the test runner
are put in module `test/testutil.lua` while the functions that are run
in the context of the test session are put in
`test/functional/testnvim.lua`.
Closes https://github.com/neovim/neovim/issues/27004.
PROBLEM: `vim.treesitter.get_node()` does not recognize the `lang` in
the option table. This option was used in somewhere else, for instance,
`vim.treesitter.dev` (for `inspect_tree`) but was never implemented.
SOLUTION: Make `get_node()` correctly use `opts.lang` when getting a
treesitter parser.
Unfortunately the gc=false objects can refer to a dangling tree if the
gc=true tree was freed first. This reuses the same tree object as the
node itself is keeping alive via the uservalue of the node userdata.
(wrapped in a table due to lua 5.1 restrictions)
Problem: `push_tree`, every time its called for the same TSTree with
`do_copy=false` argument, creates a new userdata for it. Each userdata,
when garbage collected, frees the same TSTree C object.
Solution: Add flag to userdata, which indicates, should C object,
which userdata points to, be freed, when userdata is garbage collected.
