chore: add clippy::string_slice

Fixes: https://github.com/ratatui-org/ratatui/issues/1056

Cargo.toml

@@ -99,6 +99,7 @@ string_slice = "warn"
 string_to_string = "warn"
 unnecessary_self_imports = "warn"
 use_self = "warn"
+string_slice = "warn"
 
 [features]
 #! The crate provides a set of optional features that can be enabled in your `cargo.toml` file.

src/style/color.rs

@@ -313,7 +313,16 @@ impl FromStr for Color {
                 _ => {
                     if let Ok(index) = s.parse::<u8>() {
                         Self::Indexed(index)
-                    } else if let Some((r, g, b)) = parse_hex_color(s) {
+                    } else if let (Ok(r), Ok(g), Ok(b)) = {
+                        if !s.starts_with('#') || s.len() != 7 {
+                            return Err(ParseColorError);
+                        }
+                        (
+                            u8::from_str_radix(&s.chars().skip(1).take(2).collect::<String>(), 16),
+                            u8::from_str_radix(&s.chars().skip(3).take(2).collect::<String>(), 16),
+                            u8::from_str_radix(&s.chars().skip(5).take(2).collect::<String>(), 16),
+                        )
+                    } {
                         Self::Rgb(r, g, b)
                     } else {
                         return Err(ParseColorError);

src/widgets/reflow.rs

@@ -1,3 +1,7 @@
+// The code that works on text pays attention to unicode in this file by working in graphemes
+// instead of byte indexes. This is important for languages that use double-width characters.
+#![allow(clippy::string_slice)]
+
 use std::{collections::VecDeque, vec::IntoIter};
 
 use unicode_segmentation::UnicodeSegmentation;