Add exit dialog when entering passphrase

Fixes / required changes:
* Issue #510 'Behavior of back button confusing when entering password'
* Updated test suite accordingly

src/seedsigner/gui/screens/seed_screens.py

@@ -850,11 +850,11 @@ class SeedAddPassphraseScreen(BaseTopNavScreen):
                 self.hw_button3.is_selected = True
                 self.hw_button3.render()
                 self.renderer.show_image()
-                return self.passphrase
+                return self.passphrase, None
 
             elif input == HardwareButtonsConstants.KEY_PRESS and self.top_nav.is_selected:
                 # Back button clicked
-                return self.top_nav.selected_button
+                return self.passphrase, self.top_nav.selected_button
 
             # Check for keyboard swaps
             if input == HardwareButtonsConstants.KEY1:

src/seedsigner/views/seed_views.py

@@ -323,19 +323,51 @@ class SeedAddPassphraseView(View):
 
 
     def run(self):
-        ret = self.run_screen(seed_screens.SeedAddPassphraseScreen, passphrase=self.seed.passphrase)
+        ret_passphrase, ret_btn = self.run_screen(seed_screens.SeedAddPassphraseScreen, passphrase=self.seed.passphrase)
 
-        if ret == RET_CODE__BACK_BUTTON:
-            return Destination(BackStackView)
-        
         # The new passphrase will be the return value; it might be empty.
-        self.seed.set_passphrase(ret)
-        if len(self.seed.passphrase) > 0:
+        self.seed.set_passphrase(ret_passphrase)
+        if ret_btn == RET_CODE__BACK_BUTTON:
+            if len(self.seed.passphrase) > 0:
+                return Destination(SeedAddPassphraseExitDialogView)
+            else:
+                return Destination(BackStackView)
+        elif len(self.seed.passphrase) > 0:
             return Destination(SeedReviewPassphraseView)
         else:
             return Destination(SeedFinalizeView)
 
 
+class SeedAddPassphraseExitDialogView(View):
+    EXIT = ("Exit", None, None, "red")
+    CONTINUE = "Continue editing"
+
+    def __init__(self):
+        super().__init__()
+        self.seed = self.controller.storage.get_pending_seed()
+
+
+    def run(self):
+        passphrase = self.seed.passphrase
+
+        button_data = [self.EXIT, self.CONTINUE]
+        
+        selected_menu_num = self.run_screen(
+            WarningScreen,
+            title="Exit",
+            status_headline=None,
+            text=f"Please confirm that you want to exit",
+            show_back_button=False,
+            button_data=button_data,
+        )
+
+        if button_data[selected_menu_num] == self.EXIT:
+            self.seed.set_passphrase("")
+            return Destination(SeedFinalizeView)
+        
+        elif button_data[selected_menu_num] == self.CONTINUE:
+            return Destination(SeedAddPassphraseView)
+
 
 class SeedReviewPassphraseView(View):
     """

tests/screenshot_generator/generator.py

@@ -134,6 +134,7 @@ def test_generate_screenshots(target_locale):
             seed_views.SeedMnemonicInvalidView,
             seed_views.SeedFinalizeView,
             seed_views.SeedAddPassphraseView,
+            seed_views.SeedAddPassphraseExitDialogView,
             seed_views.SeedReviewPassphraseView,
             
             (seed_views.SeedOptionsView, dict(seed_num=0)),

tests/test_flows_psbt.py

@@ -78,7 +78,7 @@ class TestPSBTFlows(FlowTest):
 			FlowStep(psbt_views.PSBTSelectSeedView, button_data_selection=psbt_views.PSBTSelectSeedView.SCAN_SEED),
 			FlowStep(scan_views.ScanSeedQRView, before_run=load_seed_into_decoder),
 			FlowStep(seed_views.SeedFinalizeView, button_data_selection=seed_views.SeedFinalizeView.PASSPHRASE),
-			FlowStep(seed_views.SeedAddPassphraseView, screen_return_value="abc"),
+			FlowStep(seed_views.SeedAddPassphraseView, screen_return_value=("abc", None)),
 			FlowStep(seed_views.SeedReviewPassphraseView, button_data_selection=seed_views.SeedReviewPassphraseView.DONE),
 			FlowStep(seed_views.SeedOptionsView, is_redirect=True),
 			FlowStep(psbt_views.PSBTOverviewView),

tests/test_flows_seed.py

@@ -41,9 +41,14 @@ class TestSeedFlows(FlowTest):
             FlowStep(MainMenuView, button_data_selection=MainMenuView.SCAN),
             FlowStep(scan_views.ScanView, before_run=load_seed_into_decoder),  # simulate read SeedQR; ret val is ignored
             FlowStep(seed_views.SeedFinalizeView, button_data_selection=seed_views.SeedFinalizeView.PASSPHRASE),
-            FlowStep(seed_views.SeedAddPassphraseView, screen_return_value="muhpassphrase"),
+            FlowStep(seed_views.SeedAddPassphraseView, screen_return_value=("muhpassphrase",RET_CODE__BACK_BUTTON)),
+            FlowStep(seed_views.SeedAddPassphraseExitDialogView, button_data_selection=seed_views.SeedAddPassphraseExitDialogView.EXIT),
+            FlowStep(seed_views.SeedFinalizeView, button_data_selection=seed_views.SeedFinalizeView.PASSPHRASE),
+            FlowStep(seed_views.SeedAddPassphraseView, screen_return_value=("muhpassphrase",RET_CODE__BACK_BUTTON)),
+            FlowStep(seed_views.SeedAddPassphraseExitDialogView, button_data_selection=seed_views.SeedAddPassphraseExitDialogView.CONTINUE),
+            FlowStep(seed_views.SeedAddPassphraseView, screen_return_value=("muhpassphrase",None)),
             FlowStep(seed_views.SeedReviewPassphraseView, button_data_selection=seed_views.SeedReviewPassphraseView.EDIT),
-            FlowStep(seed_views.SeedAddPassphraseView, screen_return_value="muhpassphrase2"),
+            FlowStep(seed_views.SeedAddPassphraseView, screen_return_value=("muhpassphrase2",None)),
             FlowStep(seed_views.SeedReviewPassphraseView, button_data_selection=seed_views.SeedReviewPassphraseView.DONE),
             FlowStep(seed_views.SeedOptionsView),
         ])

tests/test_flows_tools.py

@@ -65,7 +65,7 @@ class TestToolsFlows(FlowTest):
         self.run_sequence(
             sequence=[
                 FlowStep(seed_views.SeedFinalizeView, button_data_selection=seed_views.SeedFinalizeView.PASSPHRASE),
-                FlowStep(seed_views.SeedAddPassphraseView, screen_return_value="mypassphrase"),
+                FlowStep(seed_views.SeedAddPassphraseView, screen_return_value=("mypassphrase",None)),
                 FlowStep(seed_views.SeedReviewPassphraseView, button_data_selection=seed_views.SeedReviewPassphraseView.DONE),
                 FlowStep(seed_views.SeedOptionsView, is_redirect=True),
                 FlowStep(seed_views.SeedExportXpubScriptTypeView),