iced-rs/iced · error

Editor should always be initialized

Error message

Editor should always be initialized

What it means

Editor stores its internals as Option<Arc<Internal>>. The field starts as Some (Editor::default builds an Internal), and every mutating helper take()s it and puts it back at the end (see with_internal_mut at editor.rs:63-78). expect("Editor should always be initialized") at editor.rs:839 therefore fires only when a previous mutating call panicked midway - after the take() but before the value was restored - leaving the Option empty.

Solutions

1. Fix the FIRST panic (often "Write font system" or "Line layout should be cached" earlier in the same log); this expect is only the follow-up
2. Recreate the editor state after any caught panic: rebuild the widget tree or re-run with_text instead of reusing the editor
3. Do not swallow panics from editor methods and continue using the same instance
4. Upgrade iced so the original panic path is fixed

Example fix

// before - keep using an editor after a caught panic
if std::panic::catch_unwind(std::panic::AssertUnwindSafe(|| editor.perform(action))).is_err() {
    editor.highlight(font, &mut hl, fmt); // panics: internals left empty
}

// after - rebuild the editor after any panic
if std::panic::catch_unwind(std::panic::AssertUnwindSafe(|| editor.perform(action))).is_err() {
    editor = Editor::with_text(&contents); // fresh internals
}

let ok = std::panic::catch_unwind(std::panic::AssertUnwindSafe(|| {
    editor.perform(action)
}));
if ok.is_err() {
    // internals were take()n and not restored: rebuild instead of reusing
    editor = Editor::with_text(&contents);
}

When it happens

Trigger: A second call to highlight/perform/update/overwrite after an earlier panic inside those methods (e.g. a "Write font system" or "Line layout should be cached" panic) left self.0 = None; re-entrant use of the same editor while a take() is in flight.

Common situations: Apps that catch panics with catch_unwind and keep running on the same widget state; background tasks re-driving an editor after a text panic; the follow-up crash in logs after a first editor panic.

Related errors

• Editor cannot have multiple strong references
• Line layout should be cached
• Write font system
• Caches must not be empty
• Create color

AI-assisted analysis of iced-rs/iced@3de451447b (2026-08-17). Data as JSON: /api/errors/7d43520c1927a758. Report an issue: GitHub.

Appendix: source

Thrown at graphics/src/text/editor.rs:839

                    .expect("Line layout should be cached")
                    .len() as i32;

                if window > visible_lines {
                    window -= visible_lines;
                    None
                } else {
                    Some(scroll.line + i)
                }
            })
            .unwrap_or(buffer.lines.len().saturating_sub(1));

        let current_line = highlighter.current_line();

        if current_line > last_visible_line {
            return;
        }

        let editor = self.0.take().expect("Editor should always be initialized");

        let mut internal =
            Arc::try_unwrap(editor).expect("Editor cannot have multiple strong references");

        let mut font_system = text::font_system().write().expect("Write font system");

        let attributes = text::to_attributes(font);

        for line in &mut buffer_mut_from_editor(&mut internal.editor).lines
            [current_line..=last_visible_line]
        {
            let mut list = cosmic_text::AttrsList::new(&attributes);

            for (range, highlight) in highlighter.highlight_line(line.text()) {
                let format = format_highlight(&highlight);

                if format.color.is_some() || format.font.is_some() {
                    list.add_span(

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