Index: node_modules/d3-transition/src/transition/schedule.js
===================================================================
--- node_modules/d3-transition/src/transition/schedule.js	(revision e4c61dd6cd86e06265bc2bd91adba84a0f04044a)
+++ node_modules/d3-transition/src/transition/schedule.js	(revision e4c61dd6cd86e06265bc2bd91adba84a0f04044a)
@@ -0,0 +1,153 @@
+import {dispatch} from "d3-dispatch";
+import {timer, timeout} from "d3-timer";
+
+var emptyOn = dispatch("start", "end", "cancel", "interrupt");
+var emptyTween = [];
+
+export var CREATED = 0;
+export var SCHEDULED = 1;
+export var STARTING = 2;
+export var STARTED = 3;
+export var RUNNING = 4;
+export var ENDING = 5;
+export var ENDED = 6;
+
+export default function(node, name, id, index, group, timing) {
+  var schedules = node.__transition;
+  if (!schedules) node.__transition = {};
+  else if (id in schedules) return;
+  create(node, id, {
+    name: name,
+    index: index, // For context during callback.
+    group: group, // For context during callback.
+    on: emptyOn,
+    tween: emptyTween,
+    time: timing.time,
+    delay: timing.delay,
+    duration: timing.duration,
+    ease: timing.ease,
+    timer: null,
+    state: CREATED
+  });
+}
+
+export function init(node, id) {
+  var schedule = get(node, id);
+  if (schedule.state > CREATED) throw new Error("too late; already scheduled");
+  return schedule;
+}
+
+export function set(node, id) {
+  var schedule = get(node, id);
+  if (schedule.state > STARTED) throw new Error("too late; already running");
+  return schedule;
+}
+
+export function get(node, id) {
+  var schedule = node.__transition;
+  if (!schedule || !(schedule = schedule[id])) throw new Error("transition not found");
+  return schedule;
+}
+
+function create(node, id, self) {
+  var schedules = node.__transition,
+      tween;
+
+  // Initialize the self timer when the transition is created.
+  // Note the actual delay is not known until the first callback!
+  schedules[id] = self;
+  self.timer = timer(schedule, 0, self.time);
+
+  function schedule(elapsed) {
+    self.state = SCHEDULED;
+    self.timer.restart(start, self.delay, self.time);
+
+    // If the elapsed delay is less than our first sleep, start immediately.
+    if (self.delay <= elapsed) start(elapsed - self.delay);
+  }
+
+  function start(elapsed) {
+    var i, j, n, o;
+
+    // If the state is not SCHEDULED, then we previously errored on start.
+    if (self.state !== SCHEDULED) return stop();
+
+    for (i in schedules) {
+      o = schedules[i];
+      if (o.name !== self.name) continue;
+
+      // While this element already has a starting transition during this frame,
+      // defer starting an interrupting transition until that transition has a
+      // chance to tick (and possibly end); see d3/d3-transition#54!
+      if (o.state === STARTED) return timeout(start);
+
+      // Interrupt the active transition, if any.
+      if (o.state === RUNNING) {
+        o.state = ENDED;
+        o.timer.stop();
+        o.on.call("interrupt", node, node.__data__, o.index, o.group);
+        delete schedules[i];
+      }
+
+      // Cancel any pre-empted transitions.
+      else if (+i < id) {
+        o.state = ENDED;
+        o.timer.stop();
+        o.on.call("cancel", node, node.__data__, o.index, o.group);
+        delete schedules[i];
+      }
+    }
+
+    // Defer the first tick to end of the current frame; see d3/d3#1576.
+    // Note the transition may be canceled after start and before the first tick!
+    // Note this must be scheduled before the start event; see d3/d3-transition#16!
+    // Assuming this is successful, subsequent callbacks go straight to tick.
+    timeout(function() {
+      if (self.state === STARTED) {
+        self.state = RUNNING;
+        self.timer.restart(tick, self.delay, self.time);
+        tick(elapsed);
+      }
+    });
+
+    // Dispatch the start event.
+    // Note this must be done before the tween are initialized.
+    self.state = STARTING;
+    self.on.call("start", node, node.__data__, self.index, self.group);
+    if (self.state !== STARTING) return; // interrupted
+    self.state = STARTED;
+
+    // Initialize the tween, deleting null tween.
+    tween = new Array(n = self.tween.length);
+    for (i = 0, j = -1; i < n; ++i) {
+      if (o = self.tween[i].value.call(node, node.__data__, self.index, self.group)) {
+        tween[++j] = o;
+      }
+    }
+    tween.length = j + 1;
+  }
+
+  function tick(elapsed) {
+    var t = elapsed < self.duration ? self.ease.call(null, elapsed / self.duration) : (self.timer.restart(stop), self.state = ENDING, 1),
+        i = -1,
+        n = tween.length;
+
+    while (++i < n) {
+      tween[i].call(node, t);
+    }
+
+    // Dispatch the end event.
+    if (self.state === ENDING) {
+      self.on.call("end", node, node.__data__, self.index, self.group);
+      stop();
+    }
+  }
+
+  function stop() {
+    self.state = ENDED;
+    self.timer.stop();
+    delete schedules[id];
+    for (var i in schedules) return; // eslint-disable-line no-unused-vars
+    delete node.__transition;
+  }
+}