Function expand_line_range_to_blocks 

pub fn expand_line_range_to_blocks(
    tree: &SyntaxNode,
    text: &str,
    start_line: usize,
    end_line: usize,
) -> Option<(usize, usize)>

Expand a 1-indexed line range to encompass complete block-level elements.

This is the public API for range formatting. It converts line numbers to byte offsets, expands to block boundaries, and returns the expanded byte range.

Arguments

• tree - The syntax tree root
• text - The original document text
• start_line - Starting line number (1-indexed, inclusive)
• end_line - Ending line number (1-indexed, inclusive)

Returns

Expanded byte range (start, end) that covers complete blocks, or None if range is invalid