Add tree-sitter based function, class navigation

1 files changed, 51 insertions, 1 deletions

diff --git a/helix-core/src/movement.rs b/helix-core/src/movement.rs
index 47fe6827..e9cd299b 100644
--- a/helix-core/src/movement.rs
+++ b/helix-core/src/movement.rs
@@ -1,6 +1,7 @@
 use std::iter;
 
 use ropey::iter::Chars;
+use tree_sitter::{Node, QueryCursor};
 
 use crate::{
     chars::{categorize_char, char_is_line_ending, CharCategory},
@@ -9,7 +10,10 @@ use crate::{
         next_grapheme_boundary, nth_next_grapheme_boundary, nth_prev_grapheme_boundary,
         prev_grapheme_boundary,
     },
-    pos_at_coords, Position, Range, RopeSlice,
+    pos_at_coords,
+    syntax::LanguageConfiguration,
+    textobject::TextObject,
+    Position, Range, RopeSlice,
 };
 
 #[derive(Debug, Copy, Clone, PartialEq, Eq)]
@@ -305,6 +309,52 @@ fn reached_target(target: WordMotionTarget, prev_ch: char, next_ch: char) -> boo
     }
 }
 
+pub fn goto_treesitter_object(
+    slice: RopeSlice,
+    range: Range,
+    object_name: &str,
+    dir: Direction,
+    slice_tree: Node,
+    lang_config: &LanguageConfiguration,
+    _count: usize,
+) -> Range {
+    let get_range = move || -> Option<Range> {
+        let byte_pos = slice.char_to_byte(range.cursor(slice));
+
+        let capture_name = format!("{}.{}", object_name, TextObject::Around);
+        let mut cursor = QueryCursor::new();
+        let nodes = lang_config.textobject_query()?.capture_nodes(
+            &capture_name,
+            slice_tree,
+            slice,
+            &mut cursor,
+        )?;
+
+        let node = match dir {
+            Direction::Forward => nodes
+                .filter(|n| n.start_byte() > byte_pos)
+                .min_by_key(|n| n.start_byte())?,
+            Direction::Backward => nodes
+                .filter(|n| n.start_byte() < byte_pos)
+                .max_by_key(|n| n.start_byte())?,
+        };
+
+        let len = slice.len_bytes();
+        let start_byte = node.start_byte();
+        let end_byte = node.end_byte();
+        if start_byte >= len || end_byte >= len {
+            return None;
+        }
+
+        let start_char = slice.byte_to_char(start_byte);
+        let end_char = slice.byte_to_char(end_byte);
+
+        // head of range should be at beginning
+        Some(Range::new(end_char, start_char))
+    };
+    get_range().unwrap_or(range)
+}
+
 #[cfg(test)]
 mod test {
     use ropey::Rope;