Closing a real modal dialog

nvda.exec() and nvda.eval() both dispatch through NVDA’s own main-thread queue and wait for the scenario to finish. That works for anything that returns on its own, but a real wx.Dialog.ShowModal() never drains that queue for as long as it’s up — confirmed against a real NVDA, not just suspected. A scenario that opens one and waits for exec() to return will sit there until exec()’s own timeout fires, with the dialog still open afterwards. `nvda.keys.press() can’t reach it either, for the same reason: it dispatches through the same queue.

The dialog’s own message loop is still alive, though — it has to be, to receive the click a real user would make. exec_nowait() and simulate_modal() reach it that way instead.

exec_nowait() queues a scenario the same way exec() does, but returns immediately instead of waiting for it to finish — freeing this process’s single-threaded RPC server to accept the next call while the scenario is stuck inside ShowModal(). A syntax error in the scenario still raises ScenarioSyntaxError synchronously, the same as exec(); only running the scenario is deferred.

simulate_modal(gesture, timeout=10.0) then runs on that next call’s own thread, never touching the blocked queue: it polls for our own process to take the foreground — what a modal dialog does unconditionally on showing — and, once it does, sends gesture as real injected keyboard input via Win32’s SendInput, the same path a human’s keypress takes. It returns False on a timeout instead of raising, since that usually means the scenario never actually opened a dialog rather than NVDA hanging. gesture is one of "enter", "escape", "tab", "space", "yes", or "no".

exec_nowait() needs --nvda-allow-eval, the same as eval()/exec(), because it runs arbitrary code inside NVDA. simulate_modal() does not need this flag because it only injects keyboard input.

Pair the two: exec_nowait() to open the dialog, simulate_modal() to close it. exec_nowait() records which window is in the foreground before it queues the scenario, and the next simulate_modal() call treats only a different window as the dialog. Calling exec() instead of exec_nowait() to open the dialog defeats the point — `simulate_modal()’s call would never even be dispatched.