[DxD] Add 'Automatic' as a mode for CloseOnExit (#13560)

## Summary of the Pull Request
Adds a new mode to `CloseOnExit`: `Automatic`. In this mode, if a process handed off by defterm terminates for whatever reason, we always close (i.e. we treat the mode as `Always`), but for processes launched by Terminal we terminate as with the `Graceful` behaviour.

## PR Checklist
* [x] Closes #13325
* [x] CLA signed. If not, go over [here](https://cla.opensource.microsoft.com/microsoft/Terminal) and sign the CLA
* [ ] Tests added/passed
* [ ] Documentation updated. If checked, please file a pull request on [our docs repo](https://github.com/MicrosoftDocs/terminal) and link it here: #xxx
* [ ] Schema updated.
* [x] I've discussed this with core contributors already. If not checked, I'm ready to accept this work might be rejected in favor of a different grand plan. Issue number where discussion took place: #xxx

## Detailed Description of the Pull Request / Additional comments

- Adds a new enum value to `CloseOnExit`
- Adds a new function to `Pane`: `FinalizeConfigurationGivenDefault`: this is a function that should be called when the pane is created via default terminal handoff, and can contain any special configurations we should set given that the pane was created via handoff

## Validation Steps Performed

(cherry picked from commit 89d57e8)
Service-Card-Id: 84836029
Service-Version: 1.15

doc/cascadia/profiles.schema.json

@@ -2086,14 +2086,15 @@
           "$ref": "#/$defs/BellSound"
         },
         "closeOnExit": {
-          "default": "graceful",
-          "description": "Sets how the profile reacts to termination or failure to launch. Possible values:\n -\"graceful\" (close when exit is typed or the process exits normally)\n -\"always\" (always close)\n -\"never\" (never close).\ntrue and false are accepted as synonyms for \"graceful\" and \"never\" respectively.",
+          "default": "automatic",
+          "description": "Sets how the profile reacts to termination or failure to launch. Possible values:\n -\"graceful\" (close when exit is typed or the process exits normally)\n -\"always\" (always close)\n -\"automatic\" (behave as \"graceful\" only for processes launched by terminal, behave as \"always\" otherwise)\n -\"never\" (never close).\ntrue and false are accepted as synonyms for \"graceful\" and \"never\" respectively.",
           "oneOf": [
             {
               "enum": [
                 "never",
                 "graceful",
-                "always"
+                "always",
+                "automatic"
               ],
               "type": "string"
             },

src/cascadia/TerminalApp/Pane.cpp

@@ -1019,9 +1019,17 @@ void Pane::_ControlConnectionStateChangedHandler(const winrt::Windows::Foundatio
 
     if (_profile)
     {
+        if (_isDefTermSession && _profile.CloseOnExit() == CloseOnExitMode::Automatic)
+        {
+            // For 'automatic', we only care about the connection state if we were launched by Terminal
+            // Since we were launched via defterm, ignore the connection state (i.e. we treat the
+            // close on exit mode as 'always', see GH #13325 for discussion)
+            Close();
+        }
+
         const auto mode = _profile.CloseOnExit();
         if ((mode == CloseOnExitMode::Always) ||
-            (mode == CloseOnExitMode::Graceful && newConnectionState == ConnectionState::Closed))
+            ((mode == CloseOnExitMode::Graceful || mode == CloseOnExitMode::Automatic) && newConnectionState == ConnectionState::Closed))
         {
             Close();
         }
@@ -3108,6 +3116,15 @@ int Pane::GetLeafPaneCount() const noexcept
     return _IsLeaf() ? 1 : (_firstChild->GetLeafPaneCount() + _secondChild->GetLeafPaneCount());
 }
 
+// Method Description:
+// - Should be called when this pane is created via a default terminal handoff
+// - Finalizes our configuration given the information that we have been
+//   created via default handoff
+void Pane::FinalizeConfigurationGivenDefault()
+{
+    _isDefTermSession = true;
+}
+
 // Method Description:
 // - Returns true if the pane or one of its descendants is read-only
 bool Pane::ContainsReadOnly() const

src/cascadia/TerminalApp/Pane.h

@@ -132,6 +132,8 @@ class Pane : public std::enable_shared_from_this<Pane>
     bool FocusPane(const std::shared_ptr<Pane> pane);
     std::shared_ptr<Pane> FindPane(const uint32_t id);
 
+    void FinalizeConfigurationGivenDefault();
+
     bool ContainsReadOnly() const;
 
     // Method Description:
@@ -241,6 +243,8 @@ class Pane : public std::enable_shared_from_this<Pane>
 
     bool _zoomed{ false };
 
+    bool _isDefTermSession{ false };
+
     winrt::Windows::Media::Playback::MediaPlayer _bellPlayer{ nullptr };
     winrt::Windows::Media::Playback::MediaPlayer::MediaEnded_revoker _mediaEndedRevoker;
 

src/cascadia/TerminalApp/TerminalPage.cpp

@@ -3270,7 +3270,11 @@ namespace winrt::TerminalApp::implementation
             // elevated version of the Terminal with that profile... that's a
             // recipe for disaster. We won't ever open up a tab in this window.
             newTerminalArgs.Elevate(false);
-            _CreateNewTabFromPane(_MakePane(newTerminalArgs, false, connection));
+            const auto newPane = _MakePane(newTerminalArgs, false, connection);
+            newPane->WalkTree([](auto pane) {
+                pane->FinalizeConfigurationGivenDefault();
+            });
+            _CreateNewTabFromPane(newPane);
 
             // Request a summon of this window to the foreground
             _SummonWindowRequestedHandlers(*this, nullptr);

src/cascadia/TerminalSettingsEditor/Resources/en-US/Resources.resw

@@ -699,6 +699,10 @@
     <value>Never close automatically</value>
     <comment>An option to choose from for the "profile termination behavior" (or "close on exit") setting. When selected, the terminal never closes, even if the process exits in a controlled or uncontrolled scenario. The user would have to manually close the terminal.</comment>
   </data>
+  <data name="Profile_CloseOnExitAutomatic.Content" xml:space="preserve">
+    <value>Automatic</value>
+    <comment>An option to choose from for the "profile termination behavior" (or "close on exit") setting. When selected, the terminal closes if the process exits in a controlled scenario successfully and the process was launched by Windows Terminal.</comment>
+  </data>
   <data name="Profile_ColorScheme.Header" xml:space="preserve">
     <value>Color scheme</value>
     <comment>Header for a control to select the scheme (or set) of colors used in the session. This is selected from a list of options managed by the user.</comment>

src/cascadia/TerminalSettingsModel/MTSMSettings.h

@@ -72,7 +72,7 @@ Author(s):
     X(bool, SuppressApplicationTitle, "suppressApplicationTitle", false)                                                                                       \
     X(guid, ConnectionType, "connectionType")                                                                                                                  \
     X(hstring, Icon, "icon", L"\uE756")                                                                                                                        \
-    X(CloseOnExitMode, CloseOnExit, "closeOnExit", CloseOnExitMode::Graceful)                                                                                  \
+    X(CloseOnExitMode, CloseOnExit, "closeOnExit", CloseOnExitMode::Automatic)                                                                                 \
     X(hstring, TabTitle, "tabTitle")                                                                                                                           \
     X(Model::BellStyle, BellStyle, "bellStyle", BellStyle::Audible)                                                                                            \
     X(bool, UseAtlasEngine, "experimental.useAtlasEngine", false)                                                                                              \

src/cascadia/TerminalSettingsModel/Profile.idl

@@ -26,7 +26,8 @@ namespace Microsoft.Terminal.Settings.Model
     {
         Never = 0,
         Graceful,
-        Always
+        Always,
+        Automatic
     };
 
     [flags]

src/cascadia/TerminalSettingsModel/TerminalSettingsSerializationHelpers.h

@@ -108,10 +108,11 @@ JSON_ENUM_MAPPER(::winrt::Microsoft::Terminal::Control::TextAntialiasingMode)
 // - Helper for converting a user-specified closeOnExit value to its corresponding enum
 JSON_ENUM_MAPPER(::winrt::Microsoft::Terminal::Settings::Model::CloseOnExitMode)
 {
-    JSON_MAPPINGS(3) = {
+    JSON_MAPPINGS(4) = {
         pair_type{ "always", ValueType::Always },
         pair_type{ "graceful", ValueType::Graceful },
         pair_type{ "never", ValueType::Never },
+        pair_type{ "automatic", ValueType::Automatic },
     };
 
     // Override mapping parser to add boolean parsing

src/cascadia/TerminalSettingsModel/defaults.json

@@ -43,7 +43,7 @@
             "icon": "ms-appx:///ProfileIcons/{61c54bbd-c2c6-5271-96e7-009a87ff44bf}.png",
             "colorScheme": "Campbell",
             "antialiasingMode": "grayscale",
-            "closeOnExit": "graceful",
+            "closeOnExit": "automatic",
             "cursorShape": "bar",
             "fontFace": "Cascadia Mono",
             "fontSize": 12,
@@ -62,7 +62,7 @@
             "icon": "ms-appx:///ProfileIcons/{0caa0dad-35be-5f56-a8ff-afceeeaa6101}.png",
             "colorScheme": "Campbell",
             "antialiasingMode": "grayscale",
-            "closeOnExit": "graceful",
+            "closeOnExit": "automatic",
             "cursorShape": "bar",
             "fontFace": "Cascadia Mono",
             "fontSize": 12,