t / chainlint / multi-line-nested-command-substitution.teston commit match-trees: use hashcpy to splice trees (f55ac43)
   1(
   2        foo &&
   3        x=$(
   4                echo bar |
   5                cat
   6        ) &&
   7        echo ok
   8) |
   9sort &&
  10(
  11        bar &&
  12        x=$(echo bar |
  13                cat
  14        ) &&
  15        y=$(echo baz |
  16                fip) &&
  17        echo fail
  18)