fn compute_len()

in src/line.rs [186:222]

• 20 lines of code
• 4 McCabe index (conditional complexity)

    fn compute_len(&mut self, sym_rva: u32, sym_len: u32) {
        // The length (in the binary) of the line is not in the pdb but we can infer it
        // based on the rva of the next line. For the last line, we can infer it because
        // we know the length of the function symbol, and we are only concerned with the
        // line records of a single function here:
        //
        // RVA     LINE NUMBER
        // 0x0001  10  <= the size of line 10 is 0x000B - 0x0001
        // 0x000B  11
        // ...
        // 0x002A  15 <= the size of line 15 is (0x0001 + sym length) - 0x002A

        if self.lines.is_empty() {
            return;
        }

        assert!(
            self.are_lines_sorted,
            "Call ensure_order() before calling compute_len()"
        );

        let lens: Vec<u32> = self.lines.windows(2).map(|w| w[1].rva - w[0].rva).collect();

        // Cannot fail since self.lines isn't empty
        let (last, lines) = self.lines.split_last_mut().unwrap();

        lines
            .iter_mut()
            .zip(lens.iter())
            .for_each(|(line, len)| line.len = *len);

        if let Some(function_end_rva) = sym_rva.checked_add(sym_len) {
            if last.rva < function_end_rva {
                last.len = function_end_rva - last.rva;
            }
        }
    }