From debdb88d1ccca3648f45d6cc5d49896f3014cfdd Mon Sep 17 00:00:00 2001
From: Dan Vanderkam <dan@dygraphs.com>
Date: Fri, 20 Jul 2012 15:35:14 -0400
Subject: [PATCH] create failing errorBars test

---
 auto_tests/tests/error_bars.js | 54 ++++++++++++++++++++++++++++++++++++++++++
 auto_tests/tests/stacked.js    |  5 ++--
 dygraph.js                     |  7 ++++++
 3 files changed, 64 insertions(+), 2 deletions(-)

diff --git a/auto_tests/tests/error_bars.js b/auto_tests/tests/error_bars.js
index c9e3a38..1ede89b 100644
--- a/auto_tests/tests/error_bars.js
+++ b/auto_tests/tests/error_bars.js
@@ -89,3 +89,57 @@ errorBarsTestCase.prototype.testErrorBarsDrawn = function() {
   CanvasAssertions.assertBalancedSaveRestore(htx);
 };
 
+errorBarsTestCase.prototype.testErrorBarsCorrectColors = function() {
+  // Two constant series with constant error.
+  var data = [
+    [0, [100, 50], [200, 50]],
+    [1, [100, 50], [200, 50]]
+  ];
+
+  var opts = {
+    errorBars: true,
+    sigma: 1.0,
+    fillAlpha: 0.15,
+    colors: ['#00ff00', '#0000ff'],
+    drawXGrid: false,
+    drawYGrid: false,
+    drawXAxis: false,
+    drawYAxis: false,
+    width: 400,
+    height: 300,
+    valueRange: [0, 300],
+    labels: ['X', 'Y1', 'Y2']
+  };
+  var graph = document.getElementById("graph");
+  var g = new Dygraph(graph, data, opts);
+
+  // y-pixels (0=top, 299=bottom)
+  //   0- 48: empty (white)
+  //  49- 98: Y2 error bar
+  //  99:     Y2 center line
+  // 100-148: Y2 error bar
+  // 149-198: Y1 error bar
+  // 199:     Y1 center line
+  // 200-248: Y1 error bar
+  // 249-299: empty (white)
+  // TODO(danvk): test the edges of these regions.
+
+  var ctx = g.hidden_.getContext("2d");  // bypass Proxy
+  var imageData = ctx.getImageData(0, 0, 400, 300);
+
+  assertEquals(400, imageData.width);
+  assertEquals(300, imageData.height);
+
+  // returns an (r, g, b, alpha) tuple for the pixel.
+  // values are in [0, 255].
+  var getPixel = function(imageData, x, y) {
+    var i = 4 * (x + imageData.width * y);
+    var d = imageData.data;
+    return [d[i], d[i+1], d[i+2], d[i+3]];
+  };
+
+  assertEquals([0, 0, 255, 38], getPixel(imageData, 200, 75));
+  assertEquals([0, 0, 255, 38], getPixel(imageData, 200, 125));
+  assertEquals([0, 255, 0, 38], getPixel(imageData, 200, 175));
+  assertEquals([0, 255, 0, 38], getPixel(imageData, 200, 225));
+}
diff --git a/auto_tests/tests/stacked.js b/auto_tests/tests/stacked.js
index f1abbf5..e1f2cbc 100644
--- a/auto_tests/tests/stacked.js
+++ b/auto_tests/tests/stacked.js
@@ -41,8 +41,9 @@ stackedTestCase.prototype.testCorrectColors = function() {
   // y pixel 100 = y1 line (green)
   // y pixels 0-99 = nothing (white)
 
-  var canvas = g.hidden_ctx_;
-  var imageData = canvas.getImageData(0, 0, 400, 300);
+  // TODO(danvk): factor this and getPixel() into a utility usable by all tests.
+  var ctx = g.hidden_ctx_;
+  var imageData = ctx.getImageData(0, 0, 400, 300);
 
   assertEquals(400, imageData.width);
   assertEquals(300, imageData.height);
diff --git a/dygraph.js b/dygraph.js
index f97494a..3a60180 100644
--- a/dygraph.js
+++ b/dygraph.js
@@ -3041,6 +3041,13 @@ Dygraph.prototype.parseArray_ = function(data) {
     for (i = 1; i < data[0].length; i++) {
       this.attrs_.labels.push("Y" + i);
     }
+  } else {
+    var num_labels = this.attr_("labels");
+    if (num_labels.length != data[0].length) {
+      this.error("Mismatch between number of labels (" + num_labels +
+          ") and number of columns in array (" + data[0].length + ")");
+      return null;
+    }
   }
 
   if (Dygraph.isDateLike(data[0][0])) {
-- 
2.7.4