Preserve tick ordering when updating axis.

Fixes #1748.

d3.js

@@ -8686,7 +8686,7 @@
       g.each(function() {
         var g = d3.select(this);
         var scale0 = this.__chart__ || scale, scale1 = this.__chart__ = scale.copy();
-        var ticks = tickValues == null ? scale1.ticks ? scale1.ticks.apply(scale1, tickArguments_) : scale1.domain() : tickValues, tickFormat = tickFormat_ == null ? scale1.tickFormat ? scale1.tickFormat.apply(scale1, tickArguments_) : d3_identity : tickFormat_, tick = g.selectAll(".tick").data(ticks, scale1), tickEnter = tick.enter().insert("g", ".domain").attr("class", "tick").style("opacity", ε), tickExit = d3.transition(tick.exit()).style("opacity", ε).remove(), tickUpdate = d3.transition(tick).style("opacity", 1), tickTransform;
+        var ticks = tickValues == null ? scale1.ticks ? scale1.ticks.apply(scale1, tickArguments_) : scale1.domain() : tickValues, tickFormat = tickFormat_ == null ? scale1.tickFormat ? scale1.tickFormat.apply(scale1, tickArguments_) : d3_identity : tickFormat_, tick = g.selectAll(".tick").data(ticks, scale1), tickEnter = tick.enter().insert("g", ".domain").attr("class", "tick").style("opacity", ε), tickExit = d3.transition(tick.exit()).style("opacity", ε).remove(), tickUpdate = d3.transition(tick.order()).style("opacity", 1), tickTransform;
         var range = d3_scaleRange(scale1), path = g.selectAll(".domain").data([ 0 ]), pathUpdate = (path.enter().append("path").attr("class", "domain"), 
         d3.transition(path));
         tickEnter.append("line");

src/svg/axis.js

@@ -30,7 +30,7 @@ d3.svg.axis = function() {
           tick = g.selectAll(".tick").data(ticks, scale1),
           tickEnter = tick.enter().insert("g", ".domain").attr("class", "tick").style("opacity", ε),
           tickExit = d3.transition(tick.exit()).style("opacity", ε).remove(),
-          tickUpdate = d3.transition(tick).style("opacity", 1),
+          tickUpdate = d3.transition(tick.order()).style("opacity", 1),
           tickTransform;
 
       // Domain.

test/svg/axis-test.js

@@ -486,6 +486,15 @@ suite.addBatch({
           assert.isFalse(t.select("text").empty());
           assert.equal(t.select("text").text(), tickFormat(ticks[i]));
         });
+      },
+      "maintains the order of tick marks": function(d3) {
+        var a = d3.svg.axis(),
+            g = d3.select("body").html("").append("g").call(a),
+            x = d3.scale.linear().domain([1, 1.5]);
+        a.scale().domain(x.domain());
+        g.call(a.ticks(10));
+        g.call(a.ticks(20));
+        assert.deepEqual(g.selectAll(".tick").data(), x.ticks(20));
       }
     }
   }