michael@0: // Test that SavedFrame.prototype.toString only shows frames whose principal is
michael@0: // subsumed by the caller's principal.
michael@0: 
michael@0: var count = 0;
michael@0: 
michael@0: // Given a string of letters |expected|, say "abc", assert that the stack
michael@0: // contains calls to a series of functions named by the next letter from
michael@0: // the string, say a, b, and then c. Younger frames appear earlier in
michael@0: // |expected| than older frames.
michael@0: function check(expected, stack) {
michael@0:   print("check(" + uneval(expected) + ") against:\n" + stack);
michael@0:   count++;
michael@0: 
michael@0:   // Extract only the function names from the stack trace. Omit the frames
michael@0:   // for the top-level evaluation, if it is present.
michael@0:   const frames = stack
michael@0:     .split("\n")
michael@0:     .filter(f => f.match(/^.@/))
michael@0:     .map(f => f.replace(/@.*$/g, ""));
michael@0: 
michael@0:   // Check the function names against the expected sequence.
michael@0:   assertEq(frames.length, expected.length);
michael@0:   for (var i = 0; i < expected.length; i++) {
michael@0:     assertEq(frames[i], expected[i]);
michael@0:   }
michael@0: }
michael@0: 
michael@0: var low = newGlobal({ principal: 0 });
michael@0: var mid = newGlobal({ principal: 0xffff });
michael@0: var high = newGlobal({ principal: 0xfffff });
michael@0: 
michael@0:      eval('function a() { check("a",        saveStack().toString()); b(); }');
michael@0: low .eval('function b() { check("b",        saveStack().toString()); c(); }');
michael@0: mid .eval('function c() { check("cba",      saveStack().toString()); d(); }');
michael@0: high.eval('function d() { check("dcba",     saveStack().toString()); e(); }');
michael@0:      eval('function e() { check("edcba",    saveStack().toString()); f(); }'); // no principal, so checks skipped
michael@0: low .eval('function f() { check("fb",       saveStack().toString()); g(); }');
michael@0: mid .eval('function g() { check("gfecba",   saveStack().toString()); h(); }');
michael@0: high.eval('function h() { check("hgfedcba", saveStack().toString());      }');
michael@0: 
michael@0: // Make everyone's functions visible to each other, as needed.
michael@0:      b = low .b;
michael@0: low .c = mid .c;
michael@0: mid .d = high.d;
michael@0: high.e =      e;
michael@0:      f = low .f;
michael@0: low .g = mid .g;
michael@0: mid .h = high.h;
michael@0: 
michael@0: low.check = mid.check = high.check = check;
michael@0: 
michael@0: // Kick the whole process off.
michael@0: a();
michael@0: 
michael@0: assertEq(count, 8);
michael@0: