From 98c451069d47714da496831cc055e6e9d028eba2 Mon Sep 17 00:00:00 2001
From: Michael Davis <mcarsondavis@gmail.com>
Date: Tue, 30 Aug 2022 21:43:18 -0500
Subject: [PATCH] Add a join_ranges command

---
 helix-core/src/selection.rs       | 13 +++++++++++++
 helix-term/src/commands.rs        | 16 ++++++++++++++++
 helix-term/src/keymap/default.rs  |  2 +-
 helix-term/tests/test/commands.rs | 20 ++++++++++++++++++++
 4 files changed, 50 insertions(+), 1 deletion(-)

diff --git a/helix-core/src/selection.rs b/helix-core/src/selection.rs
index 89de87feca570..c79f0f770a5eb 100644
--- a/helix-core/src/selection.rs
+++ b/helix-core/src/selection.rs
@@ -678,6 +678,19 @@ 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 {
diff --git a/helix-term/src/commands.rs b/helix-term/src/commands.rs
index f6aa602656113..970806ee5f266 100644
--- a/helix-term/src/commands.rs
+++ b/helix-term/src/commands.rs
@@ -451,6 +451,7 @@ 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",
     );
 }
 
@@ -5117,3 +5118,18 @@ 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" }
+    ));
+}
diff --git a/helix-term/src/keymap/default.rs b/helix-term/src/keymap/default.rs
index 3b70c7ff4973d..44e63aba2c690 100644
--- a/helix-term/src/keymap/default.rs
+++ b/helix-term/src/keymap/default.rs
@@ -129,7 +129,7 @@ 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,
diff --git a/helix-term/tests/test/commands.rs b/helix-term/tests/test/commands.rs
index e1a1e77015600..793d4d14d1a5f 100644
--- a/helix-term/tests/test/commands.rs
+++ b/helix-term/tests/test/commands.rs
@@ -198,3 +198,23 @@ async fn test_union_marker() -> anyhow::Result<()> {
 
     Ok(())
 }
+
+#[tokio::test]
+async fn test_join_selections() -> anyhow::Result<()> {
+    test((
+        indoc! {"\
+                #(foo|)#
+                bar
+                #[baz|]#"
+        },
+        "^j",
+        indoc! {"\
+                #[foo
+                bar
+                baz|]#"
+        },
+    ))
+    .await?;
+
+    Ok(())
+}