Update the jasmine matcher syntax to more recent standards.

imagediff.js

@@ -8,7 +8,7 @@
   var root = this;
   if (typeof module !== 'undefined') {
     try {
-      var Canvas = require('canvas');
+      var Canvas = require('canvas-prebuilt');
     } catch (e) {
       throw new Error(
         e.message + '\n' +
@@ -365,19 +365,16 @@
     isImageType : isImageType,
 
     toImageData : function (object) {
-      checkType(object);
       if (isImageData(object)) { return copyImageData(object); }
       return toImageData(object);
     },
 
     equal : function (a, b, tolerance) {
-      checkType(a, b);
       a = toImageData(a);
       b = toImageData(b);
       return equal(a, b, tolerance);
     },
     diff : function (a, b, options) {
-      checkType(a, b);
       a = toImageData(a);
       b = toImageData(b);
       return diff(a, b, options);

js/imagediff.js

@@ -3,7 +3,7 @@
   if (typeof module !== 'undefined') {
     var Canvas;
     try {
-      Canvas = require('canvas');
+      Canvas = require('canvas-prebuilt');
     } catch (e) {}
     module.exports = definition(root, name, Canvas);
   } else if (typeof define === 'function' && typeof define.amd === 'object') {
@@ -281,49 +281,54 @@
   jasmine = {
 
     toBeImageData : function () {
-      return imagediff.isImageData(this.actual);
+      return {
+        compare: function (actual) {
+          return {
+            pass: imagediff.isImageData(actual)
+          };
+        }
+      };
     },
 
-    toImageDiffEqual : function (expected, tolerance) {
-
-      if (typeof (document) !== UNDEFINED) {
-        this.message = function () {
-          var
-            div     = get('div'),
-            a       = get('div', '<div>Actual:</div>'),
-            b       = get('div', '<div>Expected:</div>'),
-            c       = get('div', '<div>Diff:</div>'),
-            diff    = imagediff.diff(this.actual, expected),
-            canvas  = getCanvas(),
-            context;
-
-          canvas.height = diff.height;
-          canvas.width  = diff.width;
-
-          div.style.overflow = 'hidden';
-          a.style.float = 'left';
-          b.style.float = 'left';
-          c.style.float = 'left';
-
-          context = canvas.getContext('2d');
-          context.putImageData(diff, 0, 0);
-
-          a.appendChild(toCanvas(this.actual));
-          b.appendChild(toCanvas(expected));
-          c.appendChild(canvas);
-
-          div.appendChild(a);
-          div.appendChild(b);
-          div.appendChild(c);
-
-          return [
-            div,
-            "Expected not to be equal."
-          ];
-        };
-      }
-
-      return imagediff.equal(this.actual, expected, tolerance);
+    toImageDiffEqual : function () {
+      return {
+        compare: function (actual, expected, tolerance) {
+          return {
+            pass: imagediff.equal(actual, expected, tolerance),
+            message: function () {
+              var
+                div     = get('div'),
+                a       = get('div', '<div>Actual:</div>'),
+                b       = get('div', '<div>Expected:</div>'),
+                c       = get('div', '<div>Diff:</div>'),
+                diff    = imagediff.diff(actual, expected),
+                canvas  = getCanvas(),
+                context;
+
+              canvas.height = diff.height;
+              canvas.width  = diff.width;
+
+              div.style.overflow = 'hidden';
+              a.style.float = 'left';
+              b.style.float = 'left';
+              c.style.float = 'left';
+
+              context = canvas.getContext('2d');
+              context.putImageData(diff, 0, 0);
+
+              a.appendChild(toCanvas(actual));
+              b.appendChild(toCanvas(expected));
+              c.appendChild(canvas);
+
+              div.appendChild(a);
+              div.appendChild(b);
+              div.appendChild(c);
+
+              return div;
+            }
+          };
+        }
+      };
     }
   };
 

package.json

@@ -19,10 +19,8 @@
   "contributors": [
     "Jordan Santell <@jsantell>"
   ],
-  "optionalDependencies": {
-    "canvas": "~1.2.7"
-  },
   "devDependencies": {
+    "canvas-prebuilt": "^1.6.0",
     "jasmine-node": ">=1.0.20",
     "smoosh": ">=0.3.1"
   },