feat: add basic hard-coded implementation for replace tag

helix-core/src/search.rs

@@ -17,6 +17,40 @@ impl<F: Fn(&char) -> bool> CharMatcher for F {
     }
 }
 
+pub fn find_nth_next_tag(
+    text: RopeSlice,
+    tag: &str,
+    mut pos: usize,
+    n: usize,
+) -> Option<Vec<usize>> {
+    if pos >= text.len_chars() || n == 0 {
+        return None;
+    }
+
+    let mut chars = text.chars_at(pos);
+
+    let tag = format!("</{tag}>");
+    let len = tag.len();
+
+    for _ in 0..n {
+        loop {
+            let c = chars.next()?;
+            let cloned_chars = chars.clone();
+            let stri: String = cloned_chars.take(len).collect();
+
+            pos += 1;
+
+            if stri == tag {
+                break;
+            }
+        }
+    }
+
+    let range: Vec<usize> = (pos - 1..pos + len - 1).collect();
+
+    Some(range)
+}
+
 pub fn find_nth_next<M: CharMatcher>(
     text: RopeSlice,
     char_matcher: M,
@@ -65,3 +99,37 @@ pub fn find_nth_prev(text: RopeSlice, ch: char, mut pos: usize, n: usize) -> Opt
 
     Some(pos)
 }
+
+pub fn find_nth_prev_tag(
+    text: RopeSlice,
+    tag: &str,
+    mut pos: usize,
+    n: usize,
+) -> Option<Vec<usize>> {
+    if pos == 0 || n == 0 {
+        return None;
+    }
+
+    let mut chars = text.chars_at(pos).reversed();
+
+    let tag = format!("<{tag}>");
+    let len = tag.len();
+
+    for _ in 0..n {
+        loop {
+            let c = chars.next()?;
+            let cloned_chars = chars.clone();
+            let stri: String = cloned_chars.take(len).collect();
+
+            pos -= 1;
+
+            if stri == tag {
+                break;
+            }
+        }
+    }
+
+    let range: Vec<usize> = (pos..pos + len).collect();
+
+    Some(range)
+}

helix-core/src/surround.rs

@@ -308,11 +308,62 @@ pub fn get_surround_pos(
             return Err(Error::CursorOverlap);
         }
         // ensure the positions are always paired in the forward direction
+        // e.g. [41, 214]
         change_pos.extend_from_slice(&[open_pos.min(close_pos), close_pos.max(open_pos)]);
     }
     Ok(change_pos)
 }
 
+fn find_nth_close_tag(
+    text: RopeSlice,
+    tag: &str,
+    mut pos: usize,
+    n: usize,
+) -> Result<(Vec<usize>, Vec<usize>)> {
+    // if text.len_chars() < 2 {
+    //     return Err(Error::PairNotFound);
+    // }
+    // if range.to() >= text.len_chars() {
+    //     return Err(Error::RangeExceedsText);
+    // }
+    //
+    Ok((vec![4, 7], vec![10, 13]))
+}
+
+/// like get_surround_pos, but for Tags
+pub fn get_surround_pos_tag(
+    text: RopeSlice,
+    selection: &Selection,
+    tag: &str,
+    skip: usize,
+) -> Result<Vec<usize>> {
+    let mut change_pos = Vec::new();
+
+    for &range in selection {
+        let (start1, end1, start2, end2) = {
+            let pos = range.cursor(text);
+            let range_raw = find_nth_close_tag(text, tag, pos, skip).unwrap();
+
+            let first = range_raw.0;
+            let second = range_raw.1;
+            let first_1 = first.first().unwrap();
+            let first_2 = second.last().unwrap();
+            let second_1 = first.first().unwrap();
+            let second_2 = second.last().unwrap();
+            let range_first = Range::new(*first_1, *first_2);
+            let range_last = Range::new(*second_1, *second_2);
+            (
+                range_first.from(),
+                range_first.to(),
+                range_last.from(),
+                range_last.to(),
+            )
+        };
+        change_pos.extend_from_slice(&[start1, end1, start2, end2]);
+    }
+    Ok(change_pos)
+}
+
 #[cfg(test)]
 mod test {
     use super::*;
@@ -336,6 +387,21 @@ mod test {
         );
     }
 
+    #[test]
+    fn test_get_surround_pos_tag_simple() {
+        #[rustfmt::skip]
+        let (doc, selection, expectations) =
+            rope_with_selections_and_expectations_tags(
+                "<tag>hello</tag> <MegaDiv>lol</MegaDiv>",
+                " ___   ^    ___   _______  ^   _______ "
+            );
+
+        assert_eq!(
+            get_tag_surround_pos(None, doc.slice(..), &selection, 1).unwrap(),
+            expectations
+        );
+    }
+
     #[test]
     fn test_get_surround_pos_bail_different_surround_chars() {
         #[rustfmt::skip]
@@ -445,9 +511,9 @@ mod test {
         )
     }
 
-    // Create a Rope and a matching Selection using a specification language.
-    // ^ is a single-point selection.
-    // _ is an expected index. These are returned as a Vec<usize> for use in assertions.
+    /// Create a Rope and a matching Selection using a specification language.
+    /// ^ is a single-point selection.
+    /// _ is an expected index. These are returned as a Vec<usize> for use in assertions.
     fn rope_with_selections_and_expectations(
         text: &str,
         spec: &str,
@@ -467,4 +533,42 @@ mod test {
 
         (rope, Selection::new(selections, 0), expectations)
     }
+
+    fn rope_with_selections_and_expectations_tags(
+        text: &str,
+        spec: &str,
+    ) -> (Rope, Selection, Vec<Vec<usize>>) {
+        if text.len() != spec.len() {
+            panic!("specification must match text length -- are newlines aligned?");
+        }
+
+        let rope = Rope::from(text);
+
+        let selections: SmallVec<[Range; 1]> = spec
+            .match_indices('^')
+            .map(|(i, _)| Range::point(i))
+            .collect();
+
+        let expectations: Vec<Vec<usize>> = spec
+            .char_indices()
+            .filter(|&(_, c)| c == '_')
+            .map(|(i, _)| i)
+            .fold(Vec::new(), |mut groups, idx| {
+                if let Some(last_group) = groups.last_mut() {
+                    if last_group
+                        .last()
+                        .map_or(false, |&last_idx| last_idx + 1 == idx)
+                    {
+                        last_group.push(idx);
+                    } else {
+                        groups.push(vec![idx]);
+                    }
+                } else {
+                    groups.push(vec![idx]);
+                }
+                groups
+            });
+
+        (rope, Selection::new(selections, 0), expectations)
+    }
 }

helix-term/src/commands.rs

@@ -5715,57 +5715,64 @@ fn surround_replace(cx: &mut Context) {
         let text = doc.text().slice(..);
         let selection = doc.selection(view.id);
 
-        // the first character represents the index of the first change
-        // the second character represents the index of the second change
-        let change_pos =
-            // also interested in changing this
-            match surround::get_surround_pos(doc.syntax(), text, selection, surround_ch, layer) {
+        if false {
+            let change_pos = match surround::get_surround_pos_tag(text, selection, "lol", layer) {
                 Ok(c) => c,
                 Err(err) => {
                     cx.editor.set_error(err.to_string());
                     return;
                 }
             };
+            // TODO: add back the logic for other surround changes
+        } else {
+            // TODO: obtain these values from a function
+            let change_pos: Vec<(usize, usize)> = vec![(4, 10), (13, 20), (24, 30), (33, 40)];
 
-        let selection = selection.clone();
-        let ranges: SmallVec<[Range; 1]> = change_pos.iter().map(|&p| Range::point(p)).collect();
-        doc.set_selection(
-            view.id,
-            Selection::new(ranges, selection.primary_index() * 2),
-        );
+            let selection = selection.clone();
+            let ranges: SmallVec<[Range; 1]> =
+                change_pos.iter().map(|&p| Range::new(p.0, p.1)).collect();
 
-        cx.on_next_key(move |cx, event| {
-            let (view, doc) = current!(cx.editor);
-            let to = match event.char() {
-                Some(to) => to,
-                None => return doc.set_selection(view.id, selection),
-            };
-            // we are interested in changing this specifically
-            let (open, close) = match_brackets::get_pair(to);
-
-            // the changeset has to be sorted to allow nested surrounds
-            let mut sorted_pos: Vec<(usize, char)> = Vec::new();
-            for p in change_pos.chunks(2) {
-                sorted_pos.push((p[0], open));
-                sorted_pos.push((p[1], close));
-            }
-            sorted_pos.sort_unstable();
-
-            let transaction = Transaction::change(
-                doc.text(),
-                sorted_pos.iter().map(|&pos| {
-                    // "pos" is the idx of the character we are replacing
-                    // "t" is the replacement character
-                    let mut t = Tendril::new();
-                    t.push(pos.1);
-                    log::error!("{:?}, {:?}", pos.0, Some(&t));
-                    (pos.0, pos.0 + 1, Some(t))
-                }),
+            doc.set_selection(
+                view.id,
+                Selection::new(ranges, selection.primary_index() * 2),
             );
-            doc.set_selection(view.id, selection);
-            doc.apply(&transaction, view.id);
-            exit_select_mode(cx);
-        });
+
+            cx.on_next_key(move |cx, event| {
+                let (view, doc) = current!(cx.editor);
+
+                // TODO: obtain this value from the input
+                let open = "<help>";
+                let close = "</help>";
+
+                // the changeset has to be sorted to allow nested surrounds
+                let mut sorted_pos: Vec<((usize, usize), &str)> = Vec::new();
+
+                // taking chunks of two at once to replace with <help> </help>
+                for p in change_pos.chunks(2) {
+                    let line_opening = p[0];
+                    let line_closing = p[1];
+                    sorted_pos.push((line_opening, open));
+                    sorted_pos.push((line_closing, close));
+                }
+                sorted_pos.sort_unstable();
+
+                let transaction = Transaction::change(
+                    doc.text(),
+                    sorted_pos.iter().map(|&(pos, change_tag)| {
+                        let mut tag = Tendril::new();
+                        tag.push_str(change_tag);
+
+                        // replace from pos.0 to pos.1 with t
+                        (pos.0, pos.1, Some(tag))
+                    }),
+                );
+
+                // we don't need to touch this
+                doc.set_selection(view.id, selection);
+                doc.apply(&transaction, view.id);
+                exit_select_mode(cx);
+            });
+        }
     })
 }