capture-first-frame-with-principals.js

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// Create two different globals whose compartments have two different

// principals. Test getting the first frame on the stack with some given

// principals in various configurations of JS stack and of wanting self-hosted

// frames or not.

const g1 = newGlobal({

  principal: 0xffff

});

const g2 = newGlobal({

  principal: 0xff

});

// Introduce everyone to themselves and each other.

g1.g2 = g2.g2 = g2;

g1.g1 = g2.g1 = g1;

g1.g2obj = g2.eval("new Object");

g1.evaluate(`

  const global = this;

  // Capture the stack back to the first frame in the g2 global.

  function capture(shouldIgnoreSelfHosted = true) {

    return captureFirstSubsumedFrame(global.g2obj, shouldIgnoreSelfHosted);

`, {

  fileName: "script1.js"

});

g2.evaluate(`

  const capture = g1.capture;

  function getOldestFrame(stack) {

    while (stack.parent) {

      stack = stack.parent;

    return stack;

  function dumpStack(name, stack) {

    print("Stack " + name + " =");

    while (stack) {

      print("    " + stack.functionDisplayName + " @ " + stack.source);

      stack = stack.parent;

    print();

  // When the youngest frame is not self-hosted, it doesn't matter whether or not

  // we specify that we should ignore self hosted frames when capturing the first

  // frame with the given principals.

//

  // Stack: iife1 (g2) <- capture (g1)

  (function iife1() {

    const captureTrueStack = capture(true);

    dumpStack("captureTrueStack", captureTrueStack);

    assertEq(getOldestFrame(captureTrueStack).functionDisplayName, "iife1");

    assertEq(getOldestFrame(captureTrueStack).source, "script2.js");

    const captureFalseStack = capture(false);

    dumpStack("captureFalseStack", captureFalseStack);

    assertEq(getOldestFrame(captureFalseStack).functionDisplayName, "iife1");

    assertEq(getOldestFrame(captureFalseStack).source, "script2.js");

  }());

  // When the youngest frame is a self hosted frame, we get two different

  // captured stacks depending on whether or not we ignore self-hosted frames.

//

  // Stack: iife2 (g2) <- Array.prototype.map <- capture (g1)

  (function iife2() {

    const trueStack = [true].map(capture)[0];

    dumpStack("trueStack", trueStack);

    assertEq(getOldestFrame(trueStack).functionDisplayName, "iife2");

    assertEq(getOldestFrame(trueStack).source, "script2.js");

    const falseStack = [false].map(capture)[0];

    dumpStack("falseStack", falseStack);

    assertEq(getOldestFrame(falseStack).functionDisplayName !== "iife2", true);

    assertEq(getOldestFrame(falseStack).source, "self-hosted");

  }());

`, {

  fileName: "script2.js"

});