Add simple test for d3.interpolateTransform.

test/interpolate/interpolate-transform-test.js

@@ -0,0 +1,60 @@
+var vows = require("vows"),
+    load = require("../load"),
+    assert = require("../assert");
+
+var suite = vows.describe("d3.interpolateTransform");
+
+suite.addBatch({
+  "interpolateTransform": {
+    topic: load("interpolate/transform").document(),
+    "interpolation of a decomposed transform": {
+      topic: function(d3) {
+        // Use a custom d3.transform to parse a decomposed transform, since
+        // JSDOM doesn't support consolidating SVG transform strings.
+        d3.transform = function(s) {
+          var m = s.split(/,/g).map(Number);
+          return {
+            translate: [m[0], m[1]],
+            rotate: m[2],
+            skew: m[3],
+            scale: [m[4], m[5]]
+          };
+        };
+        return d3;
+      },
+      "identity": function(d3) {
+        assert.equal(d3.interpolateTransform([0, 0, 0, 0, 1, 1] + "", [0, 0, 0, 0, 1, 1] + "")(.4), "");
+      },
+      "translate": {
+        "x": function(d3) {
+          assert.equal(d3.interpolateTransform([0, 0, 0, 0, 1, 1] + "", [10, 0, 0, 0, 1, 1] + "")(.4), "translate(4,0)");
+        },
+        "y": function(d3) {
+          assert.equal(d3.interpolateTransform([0, 0, 0, 0, 1, 1] + "", [0, 10, 0, 0, 1, 1] + "")(.4), "translate(0,4)");
+        },
+        "x and y": function(d3) {
+          assert.equal(d3.interpolateTransform([0, 0, 0, 0, 1, 1] + "", [1, 10, 0, 0, 1, 1] + "")(.4), "translate(0.4,4)");
+        }
+      },
+      "rotate": {
+        "simple": function(d3) {
+          assert.equal(d3.interpolateTransform([0, 0, -10, 0, 1, 1] + "", [0, 0, 30, 0, 1, 1] + "")(.4), "rotate(6)");
+        },
+        "with constant translate": function(d3) {
+          assert.equal(d3.interpolateTransform([5, 6, -10, 0, 1, 1] + "", [5, 6, 30, 0, 1, 1] + "")(.4), "translate(5,6)rotate(6)");
+        }
+      },
+      "skew": function(d3) {
+        assert.equal(d3.interpolateTransform([0, 0, 0, 0, 1, 1] + "", [0, 0, 0, 40, 1, 1] + "")(.4), "skewX(16)");
+      },
+      "scale": function(d3) {
+        assert.equal(d3.interpolateTransform([0, 0, 0, 0, 1, 1] + "", [0, 0, 0, 0, 10, 1] + "")(.5), "scale(5.5,1)");
+      },
+      "translate and rotate": function(d3) {
+        assert.equal(d3.interpolateTransform([0, 0, 0, 0, 1, 1] + "", [100, 0, 90, 0, 1, 1] + "")(.5), "translate(50,0)rotate(45)");
+      }
+    }
+  }
+});
+
+suite.export(module);