(gl, gl.INVALID_ENUM, "parameter unknown for samplerParameteri");
    wtu.glErrorShouldBe(gl, gl.NO_ERROR, "should be no more errors");
    gl.samplerParameterf(sampler, 0x90EA /* DEPTH_STENCIL_TEXTURE_MODE_WEBGL */, gl.DEPTH_COMPONENT);
    wtu.glErrorShouldBe(gl, gl.INVALID_ENUM, "parameter unknown for samplerParameterf");
    wtu.glErrorShouldBe(gl, gl.NO_ERROR, "should be no more errors");
}

function checkEnums() {
    debug("");
    debug("Check enums");
    shouldBe("ext.DEPTH_STENCIL_TEXTURE_MODE_WE