rust Rules

Check character boundaries in Rust

When truncating strings, ensure you check character boundaries to prevent panics with multi-byte UTF-8 characters. Bad: `rust // This can cause a panic if truncation happens in the middle of a multi-byte character let mut value = some_string; value.truncate(limit); ` Good: `rust // Check character boundaries before truncating let mut value = some_string; let mut index = limit; while !value.is_char_boundary(index) { index -= 1; } value.truncate(index); `

Prefer logging instead of panicking in Rust

Use logging instead of panicking for recoverable errors. For operations that might fail but don't compromise the entire application state, log the error and provide a fallback rather than panicking. Bad: `rust let top = editor.row_for_block(decorations.prompt_block_id, cx).unwrap(); let bottom = editor.row_for_block(decorations.end_block_id, cx).unwrap(); ` Good: `rust let scroll_target_range = maybe!({ let top = editor.row_for_block(decorations.prompt_block_id, cx)?.0 as f32; let bottom = editor.row_for_block(decorations.end_block_id, cx)?.0 as f32; Some((top, bottom)) }); if scroll_target_range.is_none() { log::error!("bug: failed to find blocks for scrolling to inline assist"); } // Use a fallback value when the operation fails let scroll_target_range = scroll_target_range.unwrap_or_else(|| { // fallback calculation }); `