Re: Embedded, Debugger-API: force stop current thread of JS execution

> On 25 Jan 2017, at 01:34, Shu-yu Guo <[email protected]> wrote:
> 
> Hi Benjamin,
> 
> Using the Debugger API to terminate execution is easy: return `null` from any Debugger handler that expects a completion value [1] to be returned. For example, returning null from a breakpoint handler or an onEnterFrame will terminate debuggee execution.
> 
> [1] https://developer.mozilla.org/en-US/docs/Tools/Debugger-API/Conventions#completion-values

Thank you! Exactly what I'm looking for!

It took me some time to find some useful example code out there. Until I looked at the test suite and there it is, blindingly obvious.

This is from js/src/jit-test/tests/debug/Frame-onStep-resumption-03.js:

    // If frame.onStep returns null, the debuggee terminates.

    var g = newGlobal('new-compartment');
    g.eval("function h() { debugger; }");

    var dbg = Debugger(g);
    var hits = 0;
    dbg.onDebuggerStatement = function (frame) {
        hits++;
        if (hits == 1) {
            var rv = frame.eval("h();\n" +
                                "throw 'fail';\n");
            assertEq(rv, null);
        } else {
            frame.older.onStep = function () { return null; };
        }
    };
    g.h();
    assertEq(hits, 2);

BK