Bug 1028418 - Part 7: Tests for caching edge cases; r=shu

// Test that the SavedFrame caching doesn't get messed up in the presence of

// cross-compartment calls.

const funcSource = "function call(f) { return f(); }";

const g1 = newGlobal();

const g2 = newGlobal();

g1.eval(funcSource);

g2.eval(funcSource);

eval(funcSource);

function doSaveStack() {

  return saveStack();

}

const captureStacksAcrossCompartmens = () =>

  [this, g1, g2].map(g => g.call(doSaveStack));

(function f0() {

  const stacks = [];

  for (var i = 0; i < 2; i++)

    stacks.push(...captureStacksAcrossCompartmens());

  const [s1, s2, s3, s4, s5, s6] = stacks;

  assertEq(s1 != s2, true);

  assertEq(s2 != s3, true);

  assertEq(s3 != s1, true);

  assertEq(s1, s4);

  assertEq(s2, s5);

  assertEq(s3, s6);

}());

// Test that the SavedFrame caching doesn't mess up counts. Specifically, that

// if we capture only the first n frames of a stack, we don't cache that stack

// and return it for when someone else captures another stack and asks for more

// frames than that last time.

function stackLength(stack) {

  return stack === null

    ? 0

    : 1 + stackLength(stack.parent);

}

(function f0() {

  (function f1() {

    (function f2() {

      (function f3() {

        (function f4() {

          (function f5() {

            (function f6() {

              (function f7() {

                (function f8() {

                  (function f9() {

                    const s1 = saveStack(3);

                    const s2 = saveStack(5);

                    const s3 = saveStack(0 /* no limit */);

                    assertEq(stackLength(s1), 3);

                    assertEq(stackLength(s2), 5);

                    assertEq(stackLength(s3), 11);

                  }());

                }());

              }());

            }());

          }());

        }());

      }());

    }());

  }());

}());