Don’t include negative zero in ticks.

Author: mbostock

src/ticks.js

@@ -20,10 +20,11 @@ export default function(start, stop, count) {
     ticks = new Array(n = Math.ceil(stop - start + 1));
     while (++i < n) ticks[i] = (start + i) * step;
   } else {
+    step = -step;
     start = Math.floor(start * step);
     stop = Math.ceil(stop * step);
-    ticks = new Array(n = Math.ceil(start - stop + 1));
-    while (++i < n) ticks[i] = (start - i) / step;
+    ticks = new Array(n = Math.ceil(stop - start + 1));
+    while (++i < n) ticks[i] = (start + i) / step;
   }
 
   if (reverse) ticks.reverse();

test/ticks-test.js

@@ -37,6 +37,11 @@ tape("ticks(start, stop, count) returns the empty array if count is infinity", f
   test.end();
 });
 
+tape("ticks(start, stop, count) does not include negative zero", function(test) {
+  test.equal(1 / array.ticks(-1, 0, 5).pop(), Infinity);
+  test.end();
+});
+
 tape("ticks(start, stop, count) returns approximately count + 1 ticks when start < stop", function(test) {
   test.deepEqual(array.ticks(  0,  1, 10), [0.0, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1.0]);
   test.deepEqual(array.ticks(  0,  1,  9), [0.0, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1.0]);