Function position_to_byte_offset

src/util.rs:352–372

Convert an LSP `Position` (line, character) to a byte offset in `content`. Characters are counted as UTF-16 code units per the LSP specification. If the position is past the end of the file, the content length is returned.

(content: &str, position: Position)

/// If the position is past the end of the file, the content length is
/// returned.
pub(crate) fn position_to_byte_offset(content: &str, position: Position) -> usize {
    let mut line = 0u32;
    let mut col = 0u32;
    for (i, ch) in content.char_indices() {
        if line == position.line && col == position.character {
            return i;
        }
        if ch == '\n' {
            if line == position.line {
                // Position is past the end of this line — clamp to newline.
                return i;
            }
            line += 1;
            col = 0;
        } else {
            col += ch.len_utf16() as u32;
        }
    }
    // Position at end of content.
    content.len()
}

/// Convert a UTF-16 column offset to a byte offset within a single line.
///