Add treesitter textobjects (#728)

* Add treesitter textobject queries

Only for Go, Python and Rust for now.

* Add tree-sitter textobjects

Only has functions and class objects as of now.

* Fix tests

* Add docs for tree-sitter textobjects

* Add guide for creating new textobject queries

* Add parameter textobject

Only parameter.inside is implemented now, parameter.around
will probably require custom predicates akin to nvim' `make-range`
since we want to select a trailing comma too (a comma will be
an anonymous node and matching against them doesn't work similar
to named nodes)

* Simplify TextObject cell init

1 files changed, 1 insertions, 0 deletions

diff --git a/helix-core/src/indent.rs b/helix-core/src/indent.rs
index d9a0155f..20f034ea 100644
--- a/helix-core/src/indent.rs
+++ b/helix-core/src/indent.rs
@@ -464,6 +464,7 @@ where
                     unit: String::from("    "),
                 }),
                 indent_query: OnceCell::new(),
+                textobject_query: OnceCell::new(),
             }],
         });