Add function parameter and return commands

helix-core/src/movement.rs

@@ -558,6 +558,54 @@ fn reached_target(target: WordMotionTarget, prev_ch: char, next_ch: char) -> boo
     }
 }
 
+pub fn goto_current_function_parameters(
+    slice: RopeSlice,
+    range: Range,
+    slice_tree: Node,
+    lang_config: &LanguageConfiguration,
+) -> Option<Range> {
+    let byte_pos = slice.char_to_byte(range.cursor(slice));
+
+    let mut cursor = QueryCursor::new();
+    let current_function_range = current_node_byte_range(
+        lang_config,
+        slice_tree,
+        slice,
+        &mut cursor,
+        "function.around",
+        byte_pos,
+    )?;
+
+    cursor.set_byte_range(current_function_range);
+
+    let parameters_node = lang_config
+        .textobject_query()?
+        .capture_nodes_any(&["parameters.around"], slice_tree, slice, &mut cursor)?
+        .next()?;
+
+    Some(Range::new(
+        slice.byte_to_char(parameters_node.start_byte()),
+        slice.byte_to_char(parameters_node.end_byte()),
+    ))
+}
+
+pub fn current_node_byte_range(
+    lang_config: &LanguageConfiguration,
+    slice_tree: Node<'_>,
+    slice: RopeSlice<'_>,
+    cursor: &mut QueryCursor,
+    node: &'static str,
+    byte_pos: usize,
+) -> Option<std::ops::Range<usize>> {
+    let current_function_range = lang_config
+        .textobject_query()?
+        .capture_nodes_any(&[node], slice_tree, slice, cursor)?
+        .filter(|func| func.byte_range().contains(&byte_pos))
+        .max_by_key(|func| func.end_byte())?
+        .byte_range();
+    Some(current_function_range)
+}
+
 /// Finds the range of the next or previous textobject in the syntax sub-tree of `node`.
 /// Returns the range in the forwards direction.
 pub fn goto_treesitter_object(

helix-term/src/commands.rs

@@ -22,11 +22,11 @@ use helix_core::{
     encoding, find_workspace,
     graphemes::{self, next_grapheme_boundary, RevRopeGraphemes},
     history::UndoKind,
-    increment, indent,
+    increment,
-    indent::IndentStyle,
+    indent::{self, IndentStyle},
     line_ending::{get_line_ending_of_str, line_end_char_index},
     match_brackets,
-    movement::{self, move_vertically_visual, Direction},
+    movement::{self, current_node_byte_range, move_vertically_visual, Direction},
     object, pos_at_coords,
     regex::{self, Regex},
     search::{self, CharMatcher},
@@ -396,6 +396,7 @@ impl MappableCommand {
         goto_declaration, "Goto declaration",
         add_newline_above, "Add newline above",
         add_newline_below, "Add newline below",
+        add_function_parameter, "Add function parameter",
         goto_type_definition, "Goto type definition",
         goto_implementation, "Goto implementation",
         goto_file_start, "Goto line number <n> else file start",
@@ -426,6 +427,7 @@ impl MappableCommand {
         goto_previous_buffer, "Goto previous buffer",
         goto_line_end_newline, "Goto newline at line end",
         goto_first_nonwhitespace, "Goto first non-blank in line",
+        goto_return_type, "Goto the return type of the current function",
         trim_selections, "Trim whitespace from selections",
         extend_to_line_start, "Extend to line start",
         extend_to_first_nonwhitespace, "Extend to first non-blank in line",
@@ -5968,6 +5970,120 @@ fn add_newline_impl(cx: &mut Context, open: Open) {
     doc.apply(&transaction, view.id);
 }
 
+fn add_function_parameter(cx: &mut Context) {
+    let (view, doc) = current!(cx.editor);
+    let text = doc.text();
+    let slice = text.slice(..);
+
+    if let Some((lang_config, syntax)) = doc.language_config().zip(doc.syntax()) {
+        let root = syntax.tree().root_node();
+
+        let selection = doc.selection(view.id).clone().into_single();
+
+        let Some(new_range) = movement::goto_current_function_parameters(
+            slice,
+            selection.ranges()[0],
+            root,
+            lang_config,
+        ) else {
+            return;
+        };
+
+        let mut cursor = helix_core::tree_sitter::QueryCursor::new();
+        cursor.set_match_limit(1);
+        cursor
+            .set_byte_range(text.char_to_byte(new_range.anchor)..text.char_to_byte(new_range.head));
+
+        let has_args = lang_config
+            .textobject_query()
+            .and_then(|q| {
+                q.capture_nodes_any(&["parameter.around"], root, slice, &mut cursor)?
+                    .next()
+            })
+            .is_some();
+
+        push_jump(view, doc);
+
+        doc.set_selection(view.id, selection.transform(|_| new_range));
+        if has_args {
+            insert_char(cx, ',');
+        }
+        collapse_selection(cx);
+        insert_mode(cx);
+    }
+    // };
+}
+
+fn goto_return_type(cx: &mut Context) {
+    let (view, doc) = current!(cx.editor);
+    let text = doc.text();
+    let slice = text.slice(..);
+
+    if let Some((lang_config, syntax)) = doc.language_config().zip(doc.syntax()) {
+        let root = syntax.tree().root_node();
+
+        let selection = doc.selection(view.id).clone().into_single();
+        let range = selection.ranges()[0];
+        let mut cursor = helix_core::tree_sitter::QueryCursor::new();
+        let byte_pos = slice.char_to_byte(range.cursor(slice));
+        let Some(func_range) = current_node_byte_range(
+            lang_config,
+            root,
+            slice,
+            &mut cursor,
+            "function.around",
+            byte_pos,
+        ) else {
+            return;
+        };
+
+        cursor.set_match_limit(1);
+        cursor.set_byte_range(func_range.clone());
+
+        let new_byte_range = if let Some(return_node) =
+            lang_config.textobject_query().and_then(|q| {
+                q.capture_nodes_any(&["return_type.around"], root, slice, &mut cursor)?
+                    .next()
+            }) {
+            return_node.byte_range()
+        } else {
+            // let parameters_range =
+            let parameters_node = lang_config.textobject_query().and_then(|q| {
+                q.capture_nodes_any(&["parameters.around"], root, slice, &mut cursor)?
+                    .next()
+                    .map(|node| node.byte_range())
+            });
+
+            cursor.set_byte_range(0..func_range.end + 1);
+            let function_body_range = current_node_byte_range(
+                lang_config,
+                root,
+                slice,
+                &mut cursor,
+                "function.inside",
+                byte_pos,
+            );
+
+            match (parameters_node, function_body_range) {
+                (Some(pr), Some(br)) => pr.end..br.start,
+                (_, Some(br)) => br.start..br.start,
+                (Some(pr), _) => pr.end..pr.end,
+                _ => {
+                    return;
+                }
+            }
+        };
+
+        push_jump(view, doc);
+        let new_range = Range::new(
+            slice.byte_to_char(new_byte_range.start),
+            slice.byte_to_char(new_byte_range.end),
+        );
+        doc.set_selection(view.id, selection.transform(|_| new_range));
+    }
+    // };
+}
+
 enum IncrementDirection {
     Increase,
     Decrease,

helix-term/src/keymap/default.rs

@@ -47,6 +47,7 @@ pub fn default() -> HashMap<Mode, KeyTrie> {
             "D" => goto_declaration,
             "y" => goto_type_definition,
             "r" => goto_reference,
+            "R" => goto_return_type,
             "i" => goto_implementation,
             "t" => goto_window_top,
             "c" => goto_window_center,
@@ -285,6 +286,7 @@ pub fn default() -> HashMap<Mode, KeyTrie> {
             "c" => toggle_comments,
             "C" => toggle_block_comments,
             "A-c" => toggle_line_comments,
+            "i" => add_function_parameter,
             "?" => command_palette,
         },
         "z" => { "View"

runtime/queries/rust/textobjects.scm

@@ -1,6 +1,11 @@
 (function_item
   body: (_) @function.inside) @function.around
 
+(parameters) @parameters.around
+
+(function_item
+    return_type: (_) @return_type.around )
+
 (closure_expression
   body: (_) @function.inside) @function.around