///|
fn fixture() -> String {
  "module leaf(input [7:0] a, output [7:0] b); assign b = a; endmodule\n" +
  "module mid(input [7:0] a, output [7:0] b); wire [7:0] n; leaf l1(a, n); leaf l2(n, b); endmodule\n" +
  "module top(input [7:0] a, output [7:0] b); wire [7:0] n; mid m1(a, n); mid m2(n, b); endmodule\n"
}

///|
fn repeat_fixture(text : String, count : Int) -> String {
  let builder = StringBuilder()
  for _ in 0.. Unit {
  let mut modules = 0
  let mut edges = 0
  let mut diagnostics = 0
  for iteration in 0..