Fixes

lib/rust/ensogl/component/text/src/buffer/rope.rs

@@ -8,3 +8,6 @@
 
 pub mod formatted;
 pub mod word;
+
+
+

lib/rust/ensogl/component/text/src/component/text.rs

@@ -1675,19 +1675,30 @@ impl TextModel {
             if range.single_line() {
                 let view_line = ViewLine::from_in_context_snapped(self, range.start.line);
                 let line = &mut lines[view_line];
-                for glyph in &mut line.glyphs[range.start.offset..range.end.offset] {
-                    glyph.set_property(property);
+                if let Some(last_index) = line.glyphs.last_valid_index() {
+                    let start = std::cmp::min(last_index, range.start.offset);
+                    let end = std::cmp::min(last_index + Column(1), range.end.offset);
+                    for glyph in &mut line.glyphs[start..end] {
+                        glyph.set_property(property);
+                    }
                 }
             } else {
                 let view_line = ViewLine::from_in_context_snapped(self, range.start.line);
                 let first_line = &mut lines[view_line];
-                for glyph in &mut first_line.glyphs[range.start.offset..] {
-                    glyph.set_property(property);
+                if let Some(last_index) = first_line.glyphs.last_valid_index() {
+                    let start = std::cmp::min(last_index, range.start.offset);
+                    for glyph in &mut first_line.glyphs[start..] {
+                        glyph.set_property(property);
+                    }
                 }
+
                 let view_line = ViewLine::from_in_context_snapped(self, range.end.line);
                 let last_line = &mut lines[view_line];
-                for glyph in &mut last_line.glyphs[..range.end.offset] {
-                    glyph.set_property(property);
+                if let Some(last_index) = last_line.glyphs.last_valid_index() {
+                    let end = std::cmp::min(last_index + Column(1), range.end.offset);
+                    for glyph in &mut last_line.glyphs[..end] {
+                        glyph.set_property(property);
+                    }
                 }
                 for line_index in range.start.line.value + 1..range.end.line.value {
                     let view_line = ViewLine::from_in_context_snapped(self, Line(line_index));

lib/rust/ensogl/component/text/src/lib.rs

@@ -4,6 +4,7 @@
 //! of [`enso_text`] crate carefully.
 
 #![recursion_limit = "1024"]
+
 // === Features ===
 #![feature(const_trait_impl)]
 #![feature(trait_alias)]
@@ -15,10 +16,12 @@
 #![feature(allocator_api)]
 #![feature(let_chains)]
 #![feature(step_trait)]
+
 // === Standard Linter Configuration ===
 #![deny(non_ascii_idents)]
 #![warn(unsafe_code)]
 #![allow(clippy::let_and_return)]
+
 // === Non-Standard Linter Configuration ===
 #![warn(missing_copy_implementations)]
 #![warn(missing_debug_implementations)]

lib/rust/prelude/src/data/non_empty_vec.rs

@@ -63,6 +63,12 @@ impl<T, I> NonEmptyVec<T, I> {
         self.elems.len()
     }
 
+    /// Return the last valid index.
+    pub fn last_valid_index(&self) -> I
+    where I: From<usize> {
+        (self.len() - 1).into()
+    }
+
     /// Construct a `NonEmptyVec` containing a single element.
     ///
     /// # Examples

lib/rust/prelude/src/data/vec_indexed_by.rs

@@ -76,6 +76,16 @@ where A: Allocator
         self.vec.len()
     }
 
+    /// Return the last valid index, if any.
+    pub fn last_valid_index(&self) -> Option<I>
+    where I: From<usize> {
+        if self.vec.is_empty() {
+            None
+        } else {
+            Some((self.len() - 1).into())
+        }
+    }
+
     /// Check if the vector is empty.
     pub fn is_empty(&self) -> bool {
         self.vec.is_empty()