Just try some things.

This is work that I was doing during #2455 to try and get the TabTests working again. It doesn't work, as much as I'd like them to.

  I have mail out to try and get them working but I think we're stumped right now.

src/cascadia/LocalTests_TerminalApp/SettingsTests.cpp

@@ -32,6 +32,9 @@ namespace TerminalAppLocalTests
 
         TEST_METHOD(TryCreateWinRTType);
         TEST_METHOD(ValidateProfilesExist);
+        TEST_METHOD(FindMissingProfile);
+        TEST_METHOD(MakeSettingsForProfileThatDoesntExist);
+        TEST_METHOD(MakeSettingsForDefaultProfileThatDoesntExist);
         TEST_METHOD(ValidateDefaultProfileExists);
         TEST_METHOD(ValidateDuplicateProfiles);
         TEST_METHOD(ValidateManyWarnings);
@@ -127,6 +130,154 @@ namespace TerminalAppLocalTests
         }
     }
 
+    void SettingsTests::FindMissingProfile()
+    {
+        // Test that CascadiaSettings::FindProfile returns null for a GUID that
+        // doesn't exist
+        const std::string settingsString{ R"(
+        {
+            "defaultProfile": "{6239a42c-1111-49a3-80bd-e8fdd045185c}",
+            "profiles": [
+                {
+                    "name" : "profile0",
+                    "guid": "{6239a42c-1111-49a3-80bd-e8fdd045185c}"
+                },
+                {
+                    "name" : "profile1",
+                    "guid": "{6239a42c-2222-49a3-80bd-e8fdd045185c}"
+                }
+            ]
+        })" };
+        const auto settingsJsonObj = VerifyParseSucceeded(settingsString);
+        auto settings = CascadiaSettings::FromJson(settingsJsonObj);
+
+        const auto guid1 = Microsoft::Console::Utils::GuidFromString(L"{6239a42c-1111-49a3-80bd-e8fdd045185c}");
+        const auto guid2 = Microsoft::Console::Utils::GuidFromString(L"{6239a42c-2222-49a3-80bd-e8fdd045185c}");
+        const auto guid3 = Microsoft::Console::Utils::GuidFromString(L"{6239a42c-3333-49a3-80bd-e8fdd045185c}");
+
+        const Profile* const profile1 = settings->FindProfile(guid1);
+        const Profile* const profile2 = settings->FindProfile(guid2);
+        const Profile* const profile3 = settings->FindProfile(guid3);
+
+        VERIFY_IS_NOT_NULL(profile1);
+        VERIFY_IS_NOT_NULL(profile2);
+        VERIFY_IS_NULL(profile3);
+
+        VERIFY_ARE_EQUAL(L"profile0", profile1->GetName());
+        VERIFY_ARE_EQUAL(L"profile1", profile2->GetName());
+    }
+
+    void SettingsTests::MakeSettingsForProfileThatDoesntExist()
+    {
+        // Test that MakeSettings throws when the GUID doesn't exist
+        const std::string settingsString{ R"(
+        {
+            "defaultProfile": "{6239a42c-1111-49a3-80bd-e8fdd045185c}",
+            "profiles": [
+                {
+                    "name" : "profile0",
+                    "guid": "{6239a42c-1111-49a3-80bd-e8fdd045185c}",
+                    "historySize": 1
+                },
+                {
+                    "name" : "profile1",
+                    "guid": "{6239a42c-2222-49a3-80bd-e8fdd045185c}",
+                    "historySize": 2
+                }
+            ]
+        })" };
+        const auto settingsJsonObj = VerifyParseSucceeded(settingsString);
+        auto settings = CascadiaSettings::FromJson(settingsJsonObj);
+
+        const auto guid1 = Microsoft::Console::Utils::GuidFromString(L"{6239a42c-1111-49a3-80bd-e8fdd045185c}");
+        const auto guid2 = Microsoft::Console::Utils::GuidFromString(L"{6239a42c-2222-49a3-80bd-e8fdd045185c}");
+        const auto guid3 = Microsoft::Console::Utils::GuidFromString(L"{6239a42c-3333-49a3-80bd-e8fdd045185c}");
+
+        try
+        {
+            auto terminalSettings = settings->MakeSettings(guid1);
+            VERIFY_ARE_NOT_EQUAL(nullptr, terminalSettings);
+            VERIFY_ARE_EQUAL(1, terminalSettings.HistorySize());
+        }
+        catch (...)
+        {
+            VERIFY_IS_TRUE(false, L"This call to MakeSettings should succeed");
+        }
+
+        try
+        {
+            auto terminalSettings = settings->MakeSettings(guid2);
+            VERIFY_ARE_NOT_EQUAL(nullptr, terminalSettings);
+            VERIFY_ARE_EQUAL(2, terminalSettings.HistorySize());
+        }
+        catch (...)
+        {
+            VERIFY_IS_TRUE(false, L"This call to MakeSettings should succeed");
+        }
+
+        try
+        {
+            auto terminalSettings = settings->MakeSettings(guid3);
+            VERIFY_IS_TRUE(false, L"This call to MakeSettings should fail");
+        }
+        catch (...)
+        {
+            VERIFY_IS_TRUE(true, L"This call to MakeSettings successfully failed");
+        }
+
+        try
+        {
+            auto terminalSettings = settings->MakeSettings(std::nullopt);
+            VERIFY_ARE_NOT_EQUAL(nullptr, terminalSettings);
+            VERIFY_ARE_EQUAL(1, terminalSettings.HistorySize());
+        }
+        catch (...)
+        {
+            VERIFY_IS_TRUE(false, L"This call to MakeSettings should succeed");
+        }
+    }
+
+    void SettingsTests::MakeSettingsForDefaultProfileThatDoesntExist()
+    {
+        // Test that MakeSettings _doesnt_ throw when we load settings with a
+        // defaultProfile that's not in the list, we validate the settings, and
+        // then call MakeSettings(nullopt). The validation should ensure that
+        // the default profile is something reasonable
+        const std::string settingsString{ R"(
+        {
+            "defaultProfile": "{6239a42c-3333-49a3-80bd-e8fdd045185c}",
+            "profiles": [
+                {
+                    "name" : "profile0",
+                    "guid": "{6239a42c-1111-49a3-80bd-e8fdd045185c}",
+                    "historySize": 1
+                },
+                {
+                    "name" : "profile1",
+                    "guid": "{6239a42c-2222-49a3-80bd-e8fdd045185c}",
+                    "historySize": 2
+                }
+            ]
+        })" };
+        const auto settingsJsonObj = VerifyParseSucceeded(settingsString);
+        auto settings = CascadiaSettings::FromJson(settingsJsonObj);
+        settings->_ValidateSettings();
+
+        VERIFY_ARE_EQUAL(1u, settings->_warnings.size());
+        VERIFY_ARE_EQUAL(2u, settings->_profiles.size());
+        VERIFY_ARE_EQUAL(settings->_globals.GetDefaultProfile(), settings->_profiles.at(0).GetGuid());
+        try
+        {
+            auto terminalSettings = settings->MakeSettings(std::nullopt);
+            VERIFY_ARE_NOT_EQUAL(nullptr, terminalSettings);
+            VERIFY_ARE_EQUAL(1, terminalSettings.HistorySize());
+        }
+        catch (...)
+        {
+            VERIFY_IS_TRUE(false, L"This call to MakeSettings should succeed");
+        }
+    }
+
     void SettingsTests::ValidateDefaultProfileExists()
     {
         const std::string goodProfiles{ R"(

src/cascadia/LocalTests_TerminalApp/TabTests.cpp

@@ -31,7 +31,8 @@ namespace TerminalAppLocalTests
         // deploying the appx takes a bit, so use sparingly (though it will
         // deploy once per class when used like this.)
         BEGIN_TEST_CLASS(TabTests)
-            TEST_CLASS_PROPERTY(L"RunAs", L"UAP")
+            TEST_METHOD_PROPERTY(L"RunAs", L"UAP")
+            TEST_METHOD_PROPERTY(L"UAP:Host", L"PackagedCwa")
             TEST_CLASS_PROPERTY(L"UAP:AppXManifest", L"TerminalApp.LocalTests.AppxManifest.xml")
         END_TEST_CLASS()
 
@@ -43,6 +44,8 @@ namespace TerminalAppLocalTests
         TEST_METHOD(TryCreateXamlObjects);
         TEST_METHOD(TryCreateTab);
 
+        TEST_METHOD(TryDuplicateBadTab);
+
         TEST_CLASS_SETUP(ClassSetup)
         {
             winrt::init_apartment(winrt::apartment_type::single_threaded);
@@ -107,4 +110,16 @@ namespace TerminalAppLocalTests
         VERIFY_IS_NOT_NULL(newTab);
     }
 
+    void TabTests::TryDuplicateBadTab()
+    {
+        // Create a tab with a profile with GUID A
+        // Reload the settings so that GUID A is no longer in the list of profiles
+        // Try calling _DuplicateTabViewItem on tab A
+        // No new tab should be created (and more importantly, the app should not crash)
+
+        // This is a tests that was inspired by GH#2455, but at the time,
+        // GH#2472 was still not solved, so this test was not possible to be
+        // authored.
+    }
+
 }

src/cascadia/LocalTests_TerminalApp/TerminalApp.LocalTests.AppxManifest.prototype.xml

@@ -30,6 +30,10 @@
   </Properties>
   <Dependencies>
     <TargetDeviceFamily Name="Windows.Universal" MinVersion="10.0.18362.0" MaxVersionTested="10.0.18362.0" />
+    <!-- If you encounter errors deploying the test because these aren't
+    installed, try deploying the actual app package first. Sideloading this test
+    package doesn't install these dependencies if they're not already installed.
+    -->
     <PackageDependency Name="Microsoft.VCLibs.140.00.Debug" MinVersion="14.0.27023.1" Publisher="CN=Microsoft Corporation, O=Microsoft Corporation, L=Redmond, S=Washington, C=US" />
     <PackageDependency Name="Microsoft.VCLibs.140.00.Debug.UWPDesktop" MinVersion="14.0.27027.1" Publisher="CN=Microsoft Corporation, O=Microsoft Corporation, L=Redmond, S=Washington, C=US" />
   </Dependencies>

src/cascadia/TerminalApp/CascadiaSettings.cpp

@@ -451,7 +451,7 @@ TerminalSettings CascadiaSettings::MakeSettings(std::optional<GUID> profileGuidA
     const Profile* const profile = FindProfile(profileGuid);
     if (profile == nullptr)
     {
-        throw E_INVALIDARG;
+        THROW_HR(E_INVALIDARG);
     }
 
     TerminalSettings result = profile->CreateTerminalSettings(_globals.GetColorSchemes());

src/cascadia/TerminalApp/TerminalPage.cpp

@@ -333,19 +333,30 @@ namespace winrt::TerminalApp::implementation
             profileGuid = globalSettings.GetDefaultProfile();
         }
 
-        TerminalSettings settings = _settings->MakeSettings(profileGuid);
-        _CreateNewTabFromSettings(profileGuid, settings);
+        try
+        {
+            // MakeSettings might throw and E_INVALIDARG if the profile guid
+            // doesn't exist. In that case, silently do nothing.
+            TerminalSettings settings = _settings->MakeSettings(profileGuid);
+            _CreateNewTabFromSettings(profileGuid, settings);
 
-        const int tabCount = static_cast<int>(_tabs.size());
-        TraceLoggingWrite(
-            g_hTerminalAppProvider, // handle to TerminalApp tracelogging provider
-            "TabInformation",
-            TraceLoggingDescription("Event emitted upon new tab creation in TerminalApp"),
-            TraceLoggingInt32(tabCount, "TabCount", "Count of tabs curently opened in TerminalApp"),
-            TraceLoggingBool(profileIndex.has_value(), "ProfileSpecified", "Whether the new tab specified a profile explicitly"),
-            TraceLoggingGuid(profileGuid, "ProfileGuid", "The GUID of the profile spawned in the new tab"),
-            TraceLoggingKeyword(MICROSOFT_KEYWORD_MEASURES),
-            TelemetryPrivacyDataTag(PDT_ProductAndServicePerformance));
+            const int tabCount = static_cast<int>(_tabs.size());
+            TraceLoggingWrite(
+                g_hTerminalAppProvider, // handle to TerminalApp tracelogging provider
+                "TabInformation",
+                TraceLoggingDescription("Event emitted upon new tab creation in TerminalApp"),
+                TraceLoggingInt32(tabCount, "TabCount", "Count of tabs curently opened in TerminalApp"),
+                TraceLoggingBool(profileIndex.has_value(), "ProfileSpecified", "Whether the new tab specified a profile explicitly"),
+                TraceLoggingGuid(profileGuid, "ProfileGuid", "The GUID of the profile spawned in the new tab"),
+                TraceLoggingKeyword(MICROSOFT_KEYWORD_MEASURES),
+                TelemetryPrivacyDataTag(PDT_ProductAndServicePerformance));
+        }
+        CATCH_LOG();
+        // TODO: Should we display a dialog when we do nothing because we
+        // couldn't find the associated profile? This can only really happen in
+        // the duplicate tab scenario currently, but maybe in the future of
+        // keybindings with args, someone could manually open a tab/pane with
+        // specific a GUID.
     }
 
     // Method Description:
@@ -355,18 +366,29 @@ namespace winrt::TerminalApp::implementation
     // - settings: the TerminalSettings object to use to create the TerminalControl with.
     void TerminalPage::_CreateNewTabFromSettings(GUID profileGuid, TerminalSettings settings)
     {
-        // Initialize the new tab
+        // First, ensure that a profile exists with the provided GUID. If it
+        // doesn't then we're not going to be able to create a connection for
+        // it.
+        const auto* const profile = _settings->FindProfile(profileGuid);
+        if (profile == nullptr)
+        {
+            return;
+        }
+        // Initialize the new tab.
 
         // Create a connection based on the values in our settings object.
         const auto connection = _CreateConnectionFromSettings(profileGuid, settings);
+        if (!connection)
+        {
+            // If we weren't able to create a connection, then lets just bail. This should only happen if profile is nullptr, but we'll
+            return;
+        }
 
         TermControl term{ settings, connection };
 
         // Add the new tab to the list of our tabs.
         auto newTab = _tabs.emplace_back(std::make_shared<Tab>(profileGuid, term));
 
-        const auto* const profile = _settings->FindProfile(profileGuid);
-
         // Hookup our event handlers to the new terminal
         _RegisterTerminalEvents(term, newTab);
 
@@ -407,6 +429,10 @@ namespace winrt::TerminalApp::implementation
                                                                                         winrt::Microsoft::Terminal::Settings::TerminalSettings settings)
     {
         const auto* const profile = _settings->FindProfile(profileGuid);
+        if (profile == nullptr)
+        {
+            return { nullptr };
+        }
 
         TerminalConnection::ITerminalConnection connection{ nullptr };
 
@@ -589,9 +615,16 @@ namespace winrt::TerminalApp::implementation
         const auto& _tab = _tabs.at(focusedTabIndex);
 
         const auto& profileGuid = _tab->GetFocusedProfile();
-        const auto& settings = _settings->MakeSettings(profileGuid);
+        try
+        {
+            // MakeSettings might throw and E_INVALIDARG if the profile guid
+            // doesn't exist in our list of profiles. In that case, silently do
+            // nothing.
+            const auto& settings = _settings->MakeSettings(profileGuid);
 
-        _CreateNewTabFromSettings(profileGuid.value(), settings);
+            _CreateNewTabFromSettings(profileGuid.value(), settings);
+        }
+        CATCH_LOG();
     }
 
     // Method Description:
@@ -832,26 +865,33 @@ namespace winrt::TerminalApp::implementation
 
         const auto realGuid = profileGuid ? profileGuid.value() :
                                             _settings->GlobalSettings().GetDefaultProfile();
-        const auto controlSettings = _settings->MakeSettings(realGuid);
-
-        const auto controlConnection = _CreateConnectionFromSettings(realGuid, controlSettings);
-
-        const int focusedTabIndex = _GetFocusedTabIndex();
-        auto focusedTab = _tabs[focusedTabIndex];
-
-        const auto canSplit = focusedTab->CanSplitPane(splitType);
-
-        if (!canSplit)
+        try
         {
-            return;
+            // MakeSettings might throw and E_INVALIDARG if the profile guid
+            // doesn't exist in our list of profiles. In that case, silently do
+            // nothing.
+            const auto controlSettings = _settings->MakeSettings(realGuid);
+
+            const auto controlConnection = _CreateConnectionFromSettings(realGuid, controlSettings);
+
+            const int focusedTabIndex = _GetFocusedTabIndex();
+            auto focusedTab = _tabs[focusedTabIndex];
+
+            const auto canSplit = focusedTab->CanSplitPane(splitType);
+
+            if (!canSplit)
+            {
+                return;
+            }
+
+            TermControl newControl{ controlSettings, controlConnection };
+
+            // Hookup our event handlers to the new terminal
+            _RegisterTerminalEvents(newControl, focusedTab);
+
+            focusedTab->SplitPane(splitType, realGuid, newControl);
         }
-
-        TermControl newControl{ controlSettings, controlConnection };
-
-        // Hookup our event handlers to the new terminal
-        _RegisterTerminalEvents(newControl, focusedTab);
-
-        focusedTab->SplitPane(splitType, realGuid, newControl);
+        CATCH_LOG();
     }
 
     // Method Description:
@@ -1217,13 +1257,20 @@ namespace winrt::TerminalApp::implementation
         for (auto& profile : profiles)
         {
             const GUID profileGuid = profile.GetGuid();
-            TerminalSettings settings = _settings->MakeSettings(profileGuid);
-
-            for (auto& tab : _tabs)
+            try
             {
-                // Attempt to reload the settings of any panes with this profile
-                tab->UpdateSettings(settings, profileGuid);
+                // MakeSettings might throw and E_INVALIDARG if the profile guid
+                // doesn't exist in our list of profiles. In that case, silently
+                // do nothing.
+                TerminalSettings settings = _settings->MakeSettings(profileGuid);
+
+                for (auto& tab : _tabs)
+                {
+                    // Attempt to reload the settings of any panes with this profile
+                    tab->UpdateSettings(settings, profileGuid);
+                }
             }
+            CATCH_LOG();
         }
 
         // Update the icon of the tab for the currently focused profile in that tab.