core: move confirm_signal evaluation into concrete Layout implementations

Apart from making the code more correct for its users in
apps.common.confirm and elsewhere, this fixes a problem where the
confirm_signal would be scheduled before the dialog is rendered.
By making sure that handle_rendering is scheduled (i.e., listed in
create_tasks) before confirm_signal, we can be sure to render at least
once and thus appear in the UI test results.

core/src/apps/common/confirm.py

@@ -5,7 +5,6 @@ from trezor.messages.ButtonRequest import ButtonRequest
 from trezor.ui.confirm import CONFIRMED, INFO, Confirm, HoldToConfirm, InfoConfirm
 
 if __debug__:
-    from apps.debug import confirm_signal
     from trezor.ui.scroll import Paginated
 
 if False:
@@ -47,10 +46,7 @@ async def confirm(
             content, confirm, confirm_style, cancel, cancel_style, major_confirm
         )
 
-    if __debug__:
-        return await ctx.wait(dialog, confirm_signal()) is CONFIRMED
-    else:
-        return await ctx.wait(dialog) is CONFIRMED
+    return await ctx.wait(dialog) is CONFIRMED
 
 
 async def info_confirm(
@@ -72,10 +68,7 @@ async def info_confirm(
     )
 
     while True:
-        if __debug__:
-            result = await ctx.wait(dialog, confirm_signal())
-        else:
-            result = await ctx.wait(dialog)
+        result = await ctx.wait(dialog)
 
         if result is INFO:
             await info_func(ctx)
@@ -106,10 +99,7 @@ async def hold_to_confirm(
     else:
         dialog = HoldToConfirm(content, confirm, confirm_style, loader_style)
 
-    if __debug__:
-        return await ctx.wait(dialog, confirm_signal()) is CONFIRMED
-    else:
-        return await ctx.wait(dialog) is CONFIRMED
+    return await ctx.wait(dialog) is CONFIRMED
 
 
 async def require_confirm(*args: Any, **kwargs: Any) -> None:

core/src/apps/debug/__init__.py

@@ -56,7 +56,7 @@ if __debug__:
             msg = await debuglink_decision_chan.take()
             if msg.yes_no is not None:
                 await confirm_chan.put(
-                    confirm.CONFIRMED if msg.yes_no else confirm.CANCELLED
+                    ui.Result(confirm.CONFIRMED if msg.yes_no else confirm.CANCELLED)
                 )
             if msg.swipe is not None:
                 if msg.swipe == DebugSwipeDirection.UP:

core/src/apps/monero/layout/common.py

@@ -1,12 +1,9 @@
-from trezor import loop, ui, utils
+from trezor import ui, utils
 from trezor.messages import ButtonRequestType
 from trezor.messages.ButtonAck import ButtonAck
 from trezor.messages.ButtonRequest import ButtonRequest
 from trezor.ui.text import Text
 
-if __debug__:
-    from apps.debug import confirm_signal
-
 
 async def naive_pagination(
     ctx, lines, title, icon=ui.ICON_RESET, icon_color=ui.ORANGE, per_page=5
@@ -29,10 +26,7 @@ async def naive_pagination(
 
     while True:
         await ctx.call(ButtonRequest(code=ButtonRequestType.SignTx), ButtonAck)
-        if __debug__:
-            result = await loop.race(paginated, confirm_signal())
-        else:
-            result = await paginated
+        result = await paginated
         if result is CONFIRMED:
             return True
         if result is CANCELLED:

core/src/apps/webauthn/fido2.py

@@ -20,9 +20,6 @@ from apps.webauthn.resident_credentials import (
     store_resident_credential,
 )
 
-if __debug__:
-    from apps.debug import confirm_signal
-
 if False:
     from typing import Any, Coroutine, List, Optional, Tuple
 
@@ -561,19 +558,11 @@ async def verify_user(keepalive_callback: KeepaliveCallback) -> bool:
 
 
 async def confirm(*args: Any, **kwargs: Any) -> bool:
-    dialog = Confirm(*args, **kwargs)
-    if __debug__:
-        return await loop.race(dialog, confirm_signal()) is CONFIRMED
-    else:
-        return await dialog is CONFIRMED
+    return await Confirm(*args, **kwargs) is CONFIRMED
 
 
 async def confirm_pageable(*args: Any, **kwargs: Any) -> bool:
-    dialog = ConfirmPageable(*args, **kwargs)
-    if __debug__:
-        return await loop.race(dialog, confirm_signal()) is CONFIRMED
-    else:
-        return await dialog is CONFIRMED
+    return await ConfirmPageable(*args, **kwargs) is CONFIRMED
 
 
 class State:

core/src/trezor/ui/confirm.py

@@ -5,7 +5,7 @@ from trezor.ui.button import Button, ButtonCancel, ButtonConfirm, ButtonDefault
 from trezor.ui.loader import Loader, LoaderDefault
 
 if __debug__:
-    from apps.debug import swipe_signal
+    from apps.debug import swipe_signal, confirm_signal
 
 if False:
     from typing import Any, Optional, List, Tuple
@@ -79,6 +79,9 @@ class Confirm(ui.Layout):
         def read_content(self) -> List[str]:
             return self.content.read_content()
 
+        def create_tasks(self) -> Tuple[loop.Task, ...]:
+            return super().create_tasks() + (confirm_signal(),)
+
 
 class Pageable:
     def __init__(self) -> None:
@@ -217,6 +220,9 @@ class InfoConfirm(ui.Layout):
         def read_content(self) -> List[str]:
             return self.content.read_content()
 
+        def create_tasks(self) -> Tuple[loop.Task, ...]:
+            return super().create_tasks() + (confirm_signal(),)
+
 
 class HoldToConfirm(ui.Layout):
     DEFAULT_CONFIRM = "Hold To Confirm"
@@ -271,3 +277,6 @@ class HoldToConfirm(ui.Layout):
 
         def read_content(self) -> List[str]:
             return self.content.read_content()
+
+        def create_tasks(self) -> Tuple[loop.Task, ...]:
+            return super().create_tasks() + (confirm_signal(),)

core/src/trezor/ui/scroll.py

@@ -6,7 +6,7 @@ from trezor.ui.confirm import CANCELLED, CONFIRMED
 from trezor.ui.swipe import SWIPE_DOWN, SWIPE_UP, SWIPE_VERTICAL, Swipe
 
 if __debug__:
-    from apps.debug import swipe_signal, notify_layout_change
+    from apps.debug import confirm_signal, swipe_signal, notify_layout_change
 
 if False:
     from typing import List, Tuple
@@ -98,7 +98,20 @@ class Paginated(ui.Layout):
         self.on_change()
 
     def create_tasks(self) -> Tuple[loop.Task, ...]:
-        return self.handle_input(), self.handle_rendering(), self.handle_paging()
+        tasks = (
+            self.handle_input(),
+            self.handle_rendering(),
+            self.handle_paging(),
+        )  # type: Tuple[loop.Task, ...]
+
+        if __debug__:
+            # XXX This isn't strictly correct, as it allows *any* Paginated layout to be
+            # shut down by a DebugLink confirm, even if used outside of a confirm() call
+            # But we don't have any such usages in the codebase, and it doesn't actually
+            # make much sense to use a Paginated without a way to confirm it.
+            return tasks + (confirm_signal(),)
+        else:
+            return tasks
 
     def on_change(self) -> None:
         if self.one_by_one:
@@ -212,3 +225,6 @@ class PaginatedWithButtons(ui.Layout):
 
         def read_content(self) -> List[str]:
             return self.pages[self.page].read_content()
+
+        def create_tasks(self) -> Tuple[loop.Task, ...]:
+            return super().create_tasks() + (confirm_signal(),)