var CanvasAssertions = {};
/**
+ * Updates path attributes to match fill/stroke operations.
+ *
+ * This sets fillStyle to undefined for stroked paths,
+ * and strokeStyle to undefined for filled paths, to simplify
+ * matchers such as numLinesDrawn.
+ *
+ * @private
+ * @param {Array.<Object>} List of operations.
+ */
+CanvasAssertions.cleanPathAttrs_ = function(calls) {
+ var isStroked = true;
+ for (var i = calls.length - 1; i >= 0; --i) {
+ var call = calls[i];
+ var name = call.name;
+ if (name == 'stroke') {
+ isStroked = true;
+ } else if (name == 'fill') {
+ isStroked = false;
+ } else if (name == 'lineTo') {
+ if (isStroked) {
+ call.properties.fillStyle = undefined;
+ } else {
+ call.properties.strokeStyle = undefined;
+ }
+ }
+ }
+};
+
+
+/**
* Assert that a line is drawn between the two points
*
* This merely looks for one of these four possibilities:
* lineTo(p1) -> lineTo(p2)
* lineTo(p2) -> lineTo(p1)
*
- * attrs is meant to be used when you want to track things like
- * color and stroke width.
+ * predicate is meant to be used when you want to track things like
+ * color and stroke width. It can either be a hash of context properties,
+ * or a function that accepts the current call.
*/
-CanvasAssertions.assertLineDrawn = function(proxy, p1, p2, attrs) {
+CanvasAssertions.assertLineDrawn = function(proxy, p1, p2, predicate) {
+ CanvasAssertions.cleanPathAttrs_(proxy.calls__);
// found = 1 when prior loop found p1.
// found = 2 when prior loop found p2.
var priorFound = 0;
var matchp2 = CanvasAssertions.matchPixels(p2, call.args);
if (matchp1 || matchp2) {
if (priorFound == 1 && matchp2) {
-// TODO -- add property test here CanvasAssertions.matchAttributes(attrs, call.properties)
- return;
+ if (CanvasAssertions.match(predicate, call)) {
+ return;
+ }
}
if (priorFound == 2 && matchp1) {
- // TODO -- add property test here CanvasAssertions.matchAttributes(attrs, call.properties)
- return;
+ if (CanvasAssertions.match(predicate, call)) {
+ return;
+ }
}
found = matchp1 ? 1 : 2;
}
return s + "}";
};
fail("Can't find a line drawn between " + p1 +
- " and " + p2 + " with attributes " + toString(attrs));
+ " and " + p2 + " with attributes " + toString(predicate));
+};
+
+/**
+ * Return the lines drawn with specific attributes.
+ *
+ * This merely looks for one of these four possibilities:
+ * moveTo(p1) -> lineTo(p2)
+ * moveTo(p2) -> lineTo(p1)
+ * lineTo(p1) -> lineTo(p2)
+ * lineTo(p2) -> lineTo(p1)
+ *
+ * attrs is meant to be used when you want to track things like
+ * color and stroke width.
+ */
+CanvasAssertions.getLinesDrawn = function(proxy, predicate) {
+ CanvasAssertions.cleanPathAttrs_(proxy.calls__);
+ var lastCall;
+ var lines = [];
+ for (var i = 0; i < proxy.calls__.length; i++) {
+ var call = proxy.calls__[i];
+
+ if (call.name == "lineTo") {
+ if (lastCall != null) {
+ if (CanvasAssertions.match(predicate, call)) {
+ lines.push([lastCall, call]);
+ }
+ }
+ }
+
+ lastCall = (call.name === "lineTo" || call.name === "moveTo") ? call : null;
+ }
+ return lines;
+};
+
+/**
+ * Verifies that every call to context.save() has a matching call to
+ * context.restore().
+ */
+CanvasAssertions.assertBalancedSaveRestore = function(proxy) {
+ var depth = 0;
+ for (var i = 0; i < proxy.calls__.length; i++) {
+ var call = proxy.calls__[i];
+ if (call.name == "save") depth++
+ if (call.name == "restore") {
+ if (depth == 0) {
+ fail("Too many calls to restore()");
+ }
+ depth--;
+ }
+ }
+
+ if (depth > 0) {
+ fail("Missing matching 'context.restore()' calls.");
+ }
+};
+
+/**
+ * Checks how many lines of the given color have been drawn.
+ * @return {Integer} The number of lines of the given color.
+ */
+// TODO(konigsberg): change 'color' to predicate? color is the
+// common case. Possibly allow predicate to be function, hash, or
+// string representing color?
+CanvasAssertions.numLinesDrawn = function(proxy, color) {
+ CanvasAssertions.cleanPathAttrs_(proxy.calls__);
+ var num_lines = 0;
+ for (var i = 0; i < proxy.calls__.length; i++) {
+ var call = proxy.calls__[i];
+
+ // note: Don't simplify these two conditionals into one. The
+ // separation simplifies debugging tricky tests.
+ if (call.name == "lineTo") {
+ if (call.properties.strokeStyle == color) {
+ num_lines++;
+ }
+ }
+ }
+ return num_lines;
+};
+
+/**
+ * Asserts that a series of lines are connected. For example,
+ * assertConsecutiveLinesDrawn(proxy, [[x1, y1], [x2, y2], [x3, y3]], predicate)
+ * is shorthand for
+ * assertLineDrawn(proxy, [x1, y1], [x2, y2], predicate)
+ * assertLineDrawn(proxy, [x2, y2], [x3, y3], predicate)
+ */
+CanvasAssertions.assertConsecutiveLinesDrawn = function(proxy, segments, predicate) {
+ for (var i = 0; i < segments.length - 1; i++) {
+ CanvasAssertions.assertLineDrawn(proxy, segments[i], segments[i+1], predicate);
+ }
}
CanvasAssertions.matchPixels = function(expected, actual) {
// who knows what pixel a value of 5.8888 results in.
return Math.abs(expected[0] - actual[0]) < 1 &&
Math.abs(expected[1] - actual[1]) < 1;
-}
+};
-CanvasAssertions.matchAttributes = function(expected, actual) {
- for (var attr in expected) {
- if (expected.hasOwnProperty(attr) && expected[attr] != actual[attr]) {
- return false;
+/**
+ * For matching a proxy call against defined conditions.
+ * predicate can either by a hash of items compared against call.properties,
+ * or it can be a function that accepts the call, and returns true or false.
+ * If it's null, this function returns true.
+ */
+CanvasAssertions.match = function(predicate, call) {
+ if (predicate === null) {
+ return true;
+ }
+ if (typeof(predicate) === "function") {
+ return predicate(call);
+ } else {
+ for (var attr in predicate) {
+ if (predicate.hasOwnProperty(attr) && predicate[attr] != call.properties[attr]) {
+ return false;
+ }
}
}
return true;
-}
+};