Fix & regression test for Issue 358:857a6931 breaks stacked graph highlighting

diff --git a/auto_tests/tests/stacked.js b/auto_tests/tests/stacked.js
index e1f2cbc..f7ca442 100644 (file)
--- a/auto_tests/tests/stacked.js
+++ b/auto_tests/tests/stacked.js
@@ -60,3 +60,41 @@ stackedTestCase.prototype.testCorrectColors = function() {
   assertEquals([0, 0, 255, 38], getPixel(imageData, 200, 250));
   assertEquals([0, 255, 0, 38], getPixel(imageData, 200, 150));
 };
+
+// Regression test for http://code.google.com/p/dygraphs/issues/detail?id=358
+stackedTestCase.prototype.testSelectionValues = function() {
+  var opts = {
+    stackedGraph: true
+  };
+  var data = "X,Y1,Y2\n" +
+      "0,1,1\n" +
+      "1,1,1\n" +
+      "2,1,1\n" +
+      "3,1,1\n"
+  ;
+
+  var graph = document.getElementById("graph");
+  g = new Dygraph(graph, data, opts);
+
+  g.setSelection(0);
+
+  var legend = document.getElementsByClassName("dygraph-legend");
+  assertEquals(1, legend.length);
+  legend = legend[0];
+
+  assertEquals("0: Y1:1 Y2:1", legend.textContent);
+
+  // Verify that the behavior is correct with highlightSeriesOpts as well.
+  g.updateOptions({
+    highlightSeriesOpts: {
+      strokeWidth: 10
+    }
+  });
+  // NOTE: calling g.setSelection(0) here makes the test fail, due to an
+  // unrelated bug.
+  g.setSelection(1);
+  assertEquals("1: Y1:1 Y2:1", legend.textContent);
+
+  g.setSelection(0, 'Y2');
+  assertEquals("0: Y1:1 Y2:1", legend.textContent);
+};

diff --git a/dygraph-layout.js b/dygraph-layout.js
index 7e08e3e..9a0ac3d 100644 (file)
--- a/dygraph-layout.js
+++ b/dygraph-layout.js
@@ -409,12 +409,15 @@ DygraphLayout.prototype.unstackPointAtIndex = function(setIdx, row) {
 
   // The unstacked yval is equal to the current yval minus the yval of the
   // next point at the same xval.
-  var points = this.points[setIdx];
-  for (var i = row + 1; i < points.length; i++) {
-    if ((points[i].xval == point.xval) && points[i].yval) {
-      unstackedPoint.yval -= points[i].yval;
-      break;
-    }
+  if (setIdx == this.points.length - 1) {
+    // We're the last series, so no unstacking is necessary.
+    return unstackedPoint;
+  }
+
+  var points = this.points[setIdx + 1];
+  if (points[row].xval == point.xval &&  // should always be true?
+      points[row].yval) {
+    unstackedPoint.yval -= points[row].yval;
   }
 
   return unstackedPoint;