From bbd7cb7bfb3af6206d27cab181d2d17508438834 Mon Sep 17 00:00:00 2001
From: Nikita Revenco <154856872+NikitaRevenco@users.noreply.github.com>
Date: Sun, 2 Feb 2025 09:31:43 +0000
Subject: [PATCH] fix: incorrect order of index additions

---
 helix-core/src/comment.rs         |  5 +--
 helix-term/tests/test/commands.rs | 58 +++++++++++++++++++++++++++++++
 lol.html                          |  4 +--
 3 files changed, 63 insertions(+), 4 deletions(-)

diff --git a/helix-core/src/comment.rs b/helix-core/src/comment.rs
index 5a458ac2d..e5a17a79d 100644
--- a/helix-core/src/comment.rs
+++ b/helix-core/src/comment.rs
@@ -251,6 +251,7 @@ pub fn create_block_comment_transaction(
                 changes.push((from + start_pos, keep_from, None));
                 let keep_until = from + end_pos - end_token.len() - end_margin as usize + 1;
                 changes.push((keep_until, from + end_pos + 1, None));
+                // The range of characters keep_from..keep_until remain in the document
                 ranges.push(Range::new(keep_from, keep_until).with_direction(range.direction()));
             }
         } else {
@@ -311,12 +312,12 @@ pub fn toggle_block_comments(
             // to 1 element in `new_ranges`
             let (from, to, _) = changes[i * 2];
             let (from2, to2, _) = changes[i * 2 + 1];
-            *added_chars -= to2 as isize - from2 as isize;
+            *added_chars -= to as isize - from as isize;
             selections.push(Range::new(
                 (range.anchor as isize + *added_chars).try_into().unwrap(),
                 (range.head as isize + *added_chars).try_into().unwrap(),
             ));
-            *added_chars -= to as isize - from as isize;
+            *added_chars -= to2 as isize - from2 as isize;
         }
 
         changes
diff --git a/helix-term/tests/test/commands.rs b/helix-term/tests/test/commands.rs
index acaf4b714..3330eb597 100644
--- a/helix-term/tests/test/commands.rs
+++ b/helix-term/tests/test/commands.rs
@@ -852,6 +852,64 @@ async fn test_injected_comment_tokens_multiple_selections() -> anyhow::Result<()
     ))
     .await?;
 
+    // Many selections on the same line
+    test((
+        indoc! {r#"\
+            <p>C#[|o]#mment t#(|o)#ggle #(|o)#n this line sh#(|o)#uld use the HTML c#(|o)#mment t#(|o)#ken(s).</p>
+            <script type="text/javascript">
+              // Comment toggle on this line should use the javascript comment token(s).
+              foo();
+              css`
+                html {
+                  background-color: red;
+                }
+              `;
+            </script>
+        "#},
+        ":lang html<ret> C",
+        indoc! {r#"\
+            <p>C#[|<!-- o -->]#mment t#(|<!-- o -->)#ggle #(|<!-- o -->)#n this line sh#(|<!-- o -->)#uld use the HTML c#(|<!-- o -->)#mment t#(|<!-- o -->)#ken(s).</p>
+            <script type="text/javascript">
+              // Comment toggle on this line should use the javascript comment token(s).
+              foo();
+              css`
+                html {
+                  background-color: red;
+                }
+              `;
+            </script>
+        "#},
+    ))
+    .await?;
+    test((
+        indoc! {r#"\
+            <p>C#[|<!-- o -->]#mment t#(|<!-- o -->)#ggle #(|<!-- o -->)#n this line sh#(|<!-- o -->)#uld use the HTML c#(|<!-- o -->)#mment t#(|<!-- o -->)#ken(s).</p>
+            <script type="text/javascript">
+              // Comment toggle on this line should use the javascript comment token(s).
+              foo();
+              css`
+                html {
+                  background-color: red;
+                }
+              `;
+            </script>
+        "#},
+        ":lang html<ret> C",
+        indoc! {r#"\
+            <p>C#[|o]#mment t#(|o)#ggle #(|o)#n this line sh#(|o)#uld use the HTML c#(|o)#mment t#(|o)#ken(s).</p>
+            <script type="text/javascript">
+              // Comment toggle on this line should use the javascript comment token(s).
+              foo();
+              css`
+                html {
+                  background-color: red;
+                }
+              `;
+            </script>
+        "#},
+    ))
+    .await?;
+
     Ok(())
 }
 
diff --git a/lol.html b/lol.html
index 7a20664e4..4ad14046f 100644
--- a/lol.html
+++ b/lol.html
@@ -1,10 +1,10 @@
-<!-- <p>Comment toggle on this line should use the HTML comment token(s).</p> -->
+<p>Comment toggle on this line should use the HTML comment token(s).</p>
 <script type="text/javascript">
   // Comment toggle on this line should use the javascript comment token(s).
   foo();
   css`
     html {
-      background-color: #red;
+      background-color: red;
     }
   `;
 </script>