Fix: [Fuzzy-Select] Special chars cause panic

Cargo.toml

@@ -18,7 +18,7 @@ readme = "README.md"
 [features]
 default = ["editor", "password"]
 editor = ["tempfile"]
-fuzzy-select = ["fuzzy-matcher"]
+fuzzy-select = ["fuzzy-matcher", "unicode-segmentation"]
 history = []
 password = ["zeroize"]
 completion = []
@@ -28,6 +28,7 @@ console = "0.15.0"
 tempfile = { version = "3", optional = true }
 zeroize = { version = "1.1.1", optional = true }
 fuzzy-matcher = { version = "0.3.7", optional = true }
+unicode-segmentation = { version = "1.9.0", optional = true }
 
 [[example]]
 name = "password"

examples/fuzzyselect.rs

@@ -1,43 +1,46 @@
-use dialoguer::{theme::ColorfulTheme, FuzzySelect};
-
-fn main() {
-    let selections = &[
-        "Ice Cream",
-        "Vanilla Cupcake",
-        "Chocolate Muffin",
-        "A Pile of sweet, sweet mustard",
-        "Carrots",
-        "Peas",
-        "Pistacio",
-        "Mustard",
-        "Cream",
-        "Banana",
-        "Chocolate",
-        "Flakes",
-        "Corn",
-        "Cake",
-        "Tarte",
-        "Cheddar",
-        "Vanilla",
-        "Hazelnut",
-        "Flour",
-        "Sugar",
-        "Salt",
-        "Potato",
-        "French Fries",
-        "Pizza",
-        "Mousse au chocolat",
-        "Brown sugar",
-        "Blueberry",
-        "Burger",
-    ];
-
-    let selection = FuzzySelect::with_theme(&ColorfulTheme::default())
-        .with_prompt("Pick your flavor")
-        .default(0)
-        .items(&selections[..])
-        .interact()
-        .unwrap();
-
-    println!("Enjoy your {}!", selections[selection]);
-}
+use dialoguer::{theme::ColorfulTheme, FuzzySelect};
+
+fn main() {
+    let selections = &[
+        "Ice Cream",
+        "Vanilla Cupcake",
+        "Chocolate Muffin",
+        "A Pile of sweet, sweet mustard",
+        "Carrots",
+        "Peas",
+        "Pistacio",
+        "Mustard",
+        "Cream",
+        "Banana",
+        "Chocolate",
+        "Flakes",
+        "Corn",
+        "Cake",
+        "Tarte",
+        "Cheddar",
+        "Vanilla",
+        "Hazelnut",
+        "Flour",
+        "Sugar",
+        "Salt",
+        "Potato",
+        "French Fries",
+        "Pizza",
+        "Mousse au chocolat",
+        "Brown sugar",
+        "Blueberry",
+        "Burger",
+        "Käse",
+        "Döner",
+        "Blåbär",
+    ];
+
+    let selection = FuzzySelect::with_theme(&ColorfulTheme::default())
+        .with_prompt("Pick your flavor")
+        .default(0)
+        .items(&selections[..])
+        .interact()
+        .unwrap();
+
+    println!("Enjoy your {}!", selections[selection]);
+}

src/prompts/fuzzy_select.rs

@@ -2,6 +2,7 @@ use crate::theme::{SimpleTheme, TermThemeRenderer, Theme};
 use console::{Key, Term};
 use fuzzy_matcher::FuzzyMatcher;
 use std::{io, ops::Rem};
+use unicode_segmentation::UnicodeSegmentation;
 
 /// Renders a selection menu that user can fuzzy match to reduce set.
 ///
@@ -146,8 +147,9 @@ impl FuzzySelect<'_> {
 
     /// Like `interact` but allows a specific terminal to be set.
     fn _interact_on(&self, term: &Term, allow_quit: bool) -> io::Result<Option<usize>> {
-        let mut position = 0;
-        let mut search_term = String::new();
+        // This cursor iterates over the graphemes vec rather than the search term
+        let mut cursor_pos = 0;
+        let mut search_term: Vec<String> = Vec::new();
 
         let mut render = TermThemeRenderer::new(term, self.theme);
         let mut sel = self.default;
@@ -169,14 +171,20 @@ impl FuzzySelect<'_> {
         term.hide_cursor()?;
 
         loop {
+            let concatted_search_term = search_term.concat();
+            search_term = concatted_search_term
+                .graphemes(true)
+                .map(|s| s.to_string())
+                .collect::<Vec<String>>();
+
             render.clear()?;
-            render.fuzzy_select_prompt(self.prompt.as_str(), &search_term, position)?;
+            render.fuzzy_select_prompt(self.prompt.as_str(), &search_term, cursor_pos)?;
 
             // Maps all items to a tuple of item and its match score.
             let mut filtered_list = self
                 .items
                 .iter()
-                .map(|item| (item, matcher.fuzzy_match(item, &search_term)))
+                .map(|item| (item, matcher.fuzzy_match(item, &search_term.concat())))
                 .filter_map(|(item, score)| score.map(|s| (item, s)))
                 .collect::<Vec<_>>();
 
@@ -194,7 +202,7 @@ impl FuzzySelect<'_> {
                     idx == sel,
                     self.highlight_matches,
                     &matcher,
-                    &search_term,
+                    &search_term.concat(),
                 )?;
                 term.flush()?;
             }
@@ -236,12 +244,12 @@ impl FuzzySelect<'_> {
                     }
                     term.flush()?;
                 }
-                Key::ArrowLeft if position > 0 => {
-                    position -= 1;
+                Key::ArrowLeft if cursor_pos > 0 => {
+                    cursor_pos -= 1;
                     term.flush()?;
                 }
-                Key::ArrowRight if position < search_term.len() => {
-                    position += 1;
+                Key::ArrowRight if cursor_pos < search_term.len() => {
+                    cursor_pos += 1;
                     term.flush()?;
                 }
                 Key::Enter if !filtered_list.is_empty() => {
@@ -261,14 +269,14 @@ impl FuzzySelect<'_> {
                     term.show_cursor()?;
                     return Ok(sel_string_pos_in_items);
                 }
-                Key::Backspace if position > 0 => {
-                    position -= 1;
-                    search_term.remove(position);
+                Key::Backspace if cursor_pos > 0 => {
+                    cursor_pos -= 1;
+                    search_term.remove(cursor_pos);
                     term.flush()?;
                 }
                 Key::Char(chr) if !chr.is_ascii_control() => {
-                    search_term.insert(position, chr);
-                    position += 1;
+                    search_term.insert(cursor_pos, chr.to_string());
+                    cursor_pos += 1;
                     term.flush()?;
                     sel = 0;
                     starting_row = 0;

src/theme.rs

@@ -244,21 +244,23 @@ pub trait Theme {
         &self,
         f: &mut dyn fmt::Write,
         prompt: &str,
-        search_term: &str,
+        search_term: &Vec<String>,
         cursor_pos: usize,
     ) -> fmt::Result {
         if !prompt.is_empty() {
             write!(f, "{} ", prompt,)?;
         }
 
         if cursor_pos < search_term.len() {
-            let st_head = search_term[0..cursor_pos].to_string();
-            let st_tail = search_term[cursor_pos..search_term.len()].to_string();
-            let st_cursor = "|".to_string();
-            write!(f, "{}{}{}", st_head, st_cursor, st_tail)
+            let split = search_term.split_at(cursor_pos);
+            let head = split.0.concat();
+            let cursor = "|".to_string();
+            let tail = split.1.concat();
+
+            write!(f, "{}{}{}", head, cursor, tail)
         } else {
             let cursor = "|".to_string();
-            write!(f, "{}{}", search_term.to_string(), cursor)
+            write!(f, "{}{}", search_term.concat(), cursor)
         }
     }
 }
@@ -309,7 +311,7 @@ pub struct ColorfulTheme {
     /// Formats the cursor for a fuzzy select prompt
     #[cfg(feature = "fuzzy-select")]
     pub fuzzy_cursor_style: Style,
-    // Formats the highlighting if matched characters
+    // Formats the highlighting of matched characters
     #[cfg(feature = "fuzzy-select")]
     pub fuzzy_match_highlight_style: Style,
     /// Show the selections from certain prompts inline
@@ -650,7 +652,7 @@ impl Theme for ColorfulTheme {
         &self,
         f: &mut dyn fmt::Write,
         prompt: &str,
-        search_term: &str,
+        search_term: &Vec<String>, // This should be Vec<str>
         cursor_pos: usize,
     ) -> fmt::Result {
         if !prompt.is_empty() {
@@ -663,23 +665,19 @@ impl Theme for ColorfulTheme {
         }
 
         if cursor_pos < search_term.len() {
-            let st_head = search_term[0..cursor_pos].to_string();
-            let st_tail = search_term[cursor_pos + 1..search_term.len()].to_string();
-            let st_cursor = self
-                .fuzzy_cursor_style
-                .apply_to(search_term.to_string().chars().nth(cursor_pos).unwrap());
-            write!(
-                f,
-                "{} {}{}{}",
-                &self.prompt_suffix, st_head, st_cursor, st_tail
-            )
+            let split = search_term.split_at(cursor_pos);
+            let head = split.0.concat();
+            let cursor = self.fuzzy_cursor_style.apply_to(split.1.get(0).unwrap());
+            let tail = split.1[1..].concat();
+
+            write!(f, "{} {}{}{}", &self.prompt_suffix, head, cursor, tail)
         } else {
             let cursor = self.fuzzy_cursor_style.apply_to(" ");
             write!(
                 f,
                 "{} {}{}",
                 &self.prompt_suffix,
-                search_term.to_string(),
+                search_term.concat(),
                 cursor
             )
         }
@@ -780,7 +778,7 @@ impl<'a> TermThemeRenderer<'a> {
     pub fn fuzzy_select_prompt(
         &mut self,
         prompt: &str,
-        search_term: &str,
+        search_term: &Vec<String>,
         cursor_pos: usize,
     ) -> io::Result<()> {
         self.write_formatted_prompt(|this, buf| {