LayoutTests/http/tests/security/resources/canvas-video-crossorigin.js

// The following functions depend on functions in js-test-pre.js.
var canvas, context;

function testDataRetrievalAllowed() {
    // Control tests.
    debug("Testing data retrieval on an untainted canvas:");
    canvas = document.createElement("canvas");
    canvas.width = 100;
    canvas.height = 100;
    
    shouldNotThrow("canvas.getContext('2d').getImageData(0, 0, 100, 100)");
    shouldNotThrow("canvas.toDataURL()");

    // CORS tests.
    debug("<br />Testing data retrieval on a canvas tainted by a remote video pattern:");
    canvas = document.createElement("canvas");
    canvas.width = 100;
    canvas.height = 100;
    context = canvas.getContext("2d");
    context.fillStyle = context.createPattern(video, "repeat");
    context.fillRect(0, 0, 100, 100);

    shouldThrowErrorName("context.getImageData(0, 0, 100, 100)", "SecurityError");
    shouldThrowErrorName("canvas.toDataURL()", "SecurityError");
}

function testDataRetrievalForbidden(description) {
    // Control tests.
    debug("Testing data retrieval on an untainted canvas:");
    canvas = document.createElement("canvas");
    canvas.width = 100;
    canvas.height = 100;
    
    shouldNotThrow("canvas.getContext('2d').getImageData(0, 0, 100, 100)");
    shouldNotThrow("canvas.toDataURL()");

    // CORS tests.
    debug("<br />Testing data retrieval on a canvas tainted by a pattern generated by a " + description + ":");
    canvas = document.createElement("canvas");
    canvas.width = 100;
    canvas.height = 100;
    context = canvas.getContext("2d");
    context.fillStyle = context.createPattern(video, "repeat");
    context.fillRect(0, 0, 100, 100);

    shouldThrowErrorName("context.getImageData(0, 0, 100, 100)", "SecurityError");
    shouldThrowErrorName("canvas.toDataURL()", "SecurityError");
}