Add a join_ranges command

helix-core/src/selection.rs

@@ -713,6 +713,19 @@ impl Selection {
 
         Selection::new(ranges, self.primary_index)
     }
+
+    /// Creates a new selection in which all ranges are merged into one.
+    ///
+    /// The new range covers from the lowest [Range::from] to the highest
+    /// [Range::to].
+    pub fn join_ranges(&self) -> Selection {
+        // SAFETY: selections created with Selection::new are asserted to have
+        // non-empty range vectors.
+        let first = self.ranges.first().unwrap();
+        let last = self.ranges.last().unwrap();
+
+        Selection::new(smallvec![first.union(*last)], 0)
+    }
 }
 
 impl<'a> IntoIterator for &'a Selection {

helix-term/src/commands.rs

@@ -462,6 +462,7 @@ impl MappableCommand {
         select_shortest_selection_to_register, "Select shortest selection for each pair and save to register",
         select_longest_selection_from_register, "Select longest selection for each pair from register",
         select_longest_selection_to_register, "Select longest selection for each pair and save to register",
+        join_selections, "Join all selections into one",
     );
 }
 
@@ -5427,3 +5428,18 @@ pub mod range_combination {
         }
     }
 }
+
+fn join_selections(cx: &mut Context) {
+    let (view, doc) = current!(cx.editor);
+    let doc_selection = doc.selection(view.id);
+    let range_count = doc_selection.ranges().len();
+
+    let selection = doc_selection.join_ranges();
+
+    doc.set_selection(view.id, selection);
+    cx.editor.set_status(format!(
+        "Joined {} range{}",
+        range_count,
+        if range_count == 1 { "" } else { "s" }
+    ));
+}

helix-term/src/keymap/default.rs

@@ -134,7 +134,7 @@ pub fn default() -> HashMap<Mode, Keymap> {
         "^" => { "Selections"
             "s" => save_selection_to_register,
             "S" => restore_selection,
-            // "j" => join_selections,
+            "j" => join_selections,
             "c" => { "Combine selection from register"
                 "a" => append_selection_from_register,
                 "u" => union_selection_from_register,

helix-term/tests/test/commands.rs

@@ -378,3 +378,23 @@ async fn test_union_marker() -> anyhow::Result<()> {
 
     Ok(())
 }
+
+#[tokio::test(flavor = "multi_thread")]
+async fn test_join_selections() -> anyhow::Result<()> {
+    test((
+        indoc! {"\
+                #(foo|)#
+                bar
+                #[baz|]#"
+        },
+        "^j",
+        indoc! {"\
+                #[foo
+                bar
+                baz|]#"
+        },
+    ))
+    .await?;
+
+    Ok(())
+}