tById("canvas");
var gl = wtu.create3DContext(canvas, null, 2);

if (!gl) {
    testFailed("WebGL context does not exist");
} else {
    testPassed("WebGL context exists");

    runDefaultTransformFeedbackTest();
    finishTest();
}

function runDefaultTransformFeedbackTest() {
  const prog = wtu.setupTransformFeedbackProgram(gl, ["vshader", "fshader"],
      ["out_value"], gl.SEPARATE_ATTRIBS,
      ["in_value"]);
  wtu.glErrorShouldBe(gl, gl.NO_ERROR, "linking transform feedback shader should not set an e