merge helix-editor#9483 by @scdailey

Added kakoune's A-S command

Small formatting change

Updated to use grapheme helpers

Change to Range::point and fix keymap formatting

README.md

@@ -98,6 +98,7 @@ The `insert-final-newline` option now only inserts newline if the file is not em
 * [9143](https://github.com/helix-editor/helix/pull/9143) by @intarga
 * [2608](https://github.com/helix-editor/helix/pull/2608) by @Philipp-M
 * [11285](https://github.com/helix-editor/helix/pull/11285) by @drybalka
+* [9483](https://github.com/helix-editor/helix/pull/9483) by @scdailey
 
 ### Command expansions
 

book/src/keymap.md

@@ -117,6 +117,7 @@ Normal mode is the default mode when you launch helix. You can return to it from
 | `s`                   | Select all regex matches inside selections                        | `select_regex`                       |
 | `S`                   | Split selection into sub selections on regex matches              | `split_selection`                    |
 | `Alt-s`               | Split selection on newlines                                       | `split_selection_on_newline`         |
+| `Alt-S`               | Select first and last characters of each selection                | `select_first_and_last_chars`        |
 | `Alt-minus`           | Merge selections                                                  | `merge_selections`                   |
 | `Alt-_`               | Merge consecutive selections                                      | `merge_consecutive_selections`       |
 | `&`                   | Align selection in columns                                        | `align_selections`                   |

helix-term/src/commands.rs

@@ -349,6 +349,7 @@ impl MappableCommand {
         page_cursor_half_up, "Move page and cursor half up",
         page_cursor_half_down, "Move page and cursor half down",
         select_all, "Select whole document",
+        select_first_and_last_chars, "Select first and last characters of each selection",
         select_regex, "Select all regex matches inside selections",
         split_selection, "Split selections on regex matches",
         split_selection_on_newline, "Split selection on newlines",
@@ -2026,6 +2027,21 @@ fn select_all(cx: &mut Context) {
     doc.set_selection(view.id, Selection::single(0, end))
 }
 
+fn select_first_and_last_chars(cx: &mut Context) {
+    let (view, doc) = current!(cx.editor);
+    let text = doc.text().slice(..);
+
+    let selection = doc.selection(view.id).clone().transform_iter(|range| {
+        [
+            Range::point(range.from()),
+            Range::point(graphemes::prev_grapheme_boundary(text, range.to())),
+        ]
+        .into_iter()
+    });
+
+    doc.set_selection(view.id, selection);
+}
+
 fn select_regex(cx: &mut Context) {
     let reg = cx.register.unwrap_or('/');
     ui::regex_prompt(

helix-term/src/keymap/default.rs

@@ -79,6 +79,7 @@ pub fn default() -> HashMap<Mode, KeyTrie> {
 
 
         "s" => select_regex,
+        "A-S" => select_first_and_last_chars,
         "A-s" => split_selection_on_newline,
         "A-minus" => merge_selections,
         "A-_" => merge_consecutive_selections,