old_contents: #!/usr/bin/env node
  
  require('./proof')(3, function (step, Strata, tmp, load, serialize, objectify, gather, assert) {
      var strata = new Strata({ directory: tmp, leafSize: 3, branchSize: 3 })
      step(function () {
          serialize(__dirname + '/fixtures/leaf-remainder.before.json', tmp, step())
      }, function () {
          strata.open(step())
      }, function () {
          gather(step, strata)
      }, function (records) {
          assert(records, [ 'a', 'c', 'd', 'e', 'f', 'g', 'h' ], 'records')
          strata.balance(step())
      }, function () {
          gather(step, strata)
      }, function (records) {
          assert(records, [ 'a', 'c', 'd', 'e', 'f', 'g', 'h' ], 'records after balance')
  
          objectify(tmp, step())
          load(__dirname + '/fixtures/leaf-remainder.before.json', step())
      }, function (actual, expected) {
          assert(actual, expected, 'split')
      }, function() {
          strata.close(step())
      })
  })
  
new_contents: #!/usr/bin/env node
  
  require('./proof')(3, function (step, Strata, tmp, load, serialize, vivify, gather, assert) {
      var strata = new Strata({ directory: tmp, leafSize: 3, branchSize: 3 })
      step(function () {
          serialize(__dirname + '/fixtures/leaf-remainder.before.json', tmp, step())
      }, function () {
          strata.open(step())
      }, function () {
          gather(step, strata)
      }, function (records) {
          assert(records, [ 'a', 'c', 'd', 'e', 'f', 'g', 'h' ], 'records')
          strata.balance(step())
      }, function () {
          gather(step, strata)
      }, function (records) {
          assert(records, [ 'a', 'c', 'd', 'e', 'f', 'g', 'h' ], 'records after balance')
  
          vivify(tmp, step())
          load(__dirname + '/fixtures/leaf-remainder.before.json', step())
      }, function (actual, expected) {
          assert(actual, expected, 'split')
      }, function() {
          strata.close(step())
      })
  })
  
subject: Use `vivify` in `t/split/leaf-unqueued.t.js`.