Function indent_block 

pub fn indent_block(block: &str, column: usize) -> String

Re-indent block to start every non-empty line at column column. Existing leading whitespace on each line is replaced by exactly column spaces.

Empty lines are preserved as empty (no trailing whitespace), so blank lines inside the block don’t gain spurious indent.

Used to format a generated multi-line YAML block to the indent level the locator reported.