fix dynamic callback patcher: make things more versatile

[Domiii]

• use Proxy instead of function, so property modification also gets taken care of correctly.
• add analysis for multi-patching of same function/callback
  • → We have started adding that info to GlobalView → Patched_Callbacks
• ideally: don't nest patched functions/callbacks under any circumstances
  • (e.g. we might get: patchedCallback -> patchedThenCb)
  • NOTE: patchedFunctions are instrumented un-instrumented functions while patchedCbs are instrumented recorded functions. The two sets should never overlap.
• test: javascript-algorithms errors out
  • might be caused by jest-snapshot
• test: require.resolve should never be patched

Remaining Problems

Some problems are still generally unsolved (and require some hacky workaround):

• Consumer of a function relies on equality checks (e.g. addEventListener vs. removeEventListener)
  • add custom fix for removeEventListener and similar
    E.g., using our current proxy solution, f does not retain identity when handled by uninstrumented code:

  var s = new Set();
  function f() {}
  
  var p1 = new Proxy(f, {});
  var p2 = new Proxy(f, {});
  
  s.add(p1);
  
  console.assert(s.has(p2)); // assertion fails

More Future Work

• determine heuristics to detect and avoid "instrumenting the instrumentors"
  • Generally speaking, it is a bad idea to instrument the instrumenters, since that can lead to infinite loops and other bugs.
  • E.g. the old problem of graceful-fs instrumenting process.cwd → which in Node@14 was used internally by Node when reading sourcemaps when generating stacktraces → which triggered Dbux recording

Done

• fix: react-tic-tac-toe does not render if CallbackPatcher is Enabled.
• fix addEventListener -> removeEventListener callback identity