A better fix for #tab-titles-are-too-long (#2373)

### User Stories:

1. A user wants to be able to use the executable path as their starting title
    - Does anyone want this?
2. A user wants to be able to set a custom starting title, but have that title be overridable
3. A user wants to be able to set an overridable starting title, different from the profile name
    - Presumably someone will want this
4. A user totally wants to ignore the VT title and use something else
    - This will make more sense in the post [#1320] "Support runtime variables in the custom user title" settings

### Solutions:

1. `name`, `startingTitle`, `tabTitle`
    * a. `name` is only ever used as the profile name.
    * b. If `startingTitle` isn't set, then the executable path is used
    * c. If `startingTitle` is set, it's used as the initial title
    * d. If `tabTitle` is set, it overrides the title from the terminal
    * e. Current users of `tabTitle` need to manually update to the new behavior.
2. `name` as starting title, `tabTitle` as a different starting title
    * a. `name` is used as the starting title and the profile name in the dropdown
    * b. If `tabTitle` is set, we'll use that as the overridable starting title instead.
    * c. In the future, `dynamicTabTitle` or `tabTitleOverride` could be added to support [#1320]
    * d. Current users of `tabTitle` automatically get the new (different!) behavior.
    * e. User Story 1 is impossible
        - Does anyone want the behavior _ever_? Perhaps making that scenario impossible is good?
3. `name` unchanged, `tabTitle` as the starting title
    * a. `name` is only ever used as the profile name.
    * b. If `tabTitle` is set, we'll use that as the overridable starting title.
    * c. In the future, `dynamicTabTitle` or `tabTitleOverride` could be added to support [#1320]
    * d. Current users of `tabTitle` automatically get the new (different!) behavior.
4. `name` as starting title, `tabTitle` as different starting title, `suppressApplicationTitle` Boolean to force it to override
    * a. `name`, `tabTitle` work as in Solution 2.
    * b. When someone wants to be able to statically totally override that title (story 4), they can use `suppressApplicationTitle`
    * c. `suppressApplicationTitle` name is WIP
    * d.  We'll add `suppressApplicationTitle` when someone complains
    * e. If you really want story 1, use `tabTitle: c:\path\to\foo.exe` and `suppressApplicationTitle`.

[#1320]: microsoft/terminal#1320

We've decided to pursue path 4.

doc/cascadia/SettingsSchema.md

@@ -29,7 +29,7 @@ Properties listed below are specific to each unique profile.
 | `fontSize` | _Required_ | Integer | `10` | Sets the font size. |
 | `guid` | _Required_ | String | | Unique identifier of the profile. Written in registry format: `"{00000000-0000-0000-0000-000000000000}"`. |
 | `historySize` | _Required_ | Integer | `9001` | The number of lines above the ones displayed in the window you can scroll back to. |
-| `name` | _Required_ | String | `PowerShell Core` | Name of the profile. Displays in the dropdown menu. |
+| `name` | _Required_ | String | `PowerShell Core` | Name of the profile. Displays in the dropdown menu. <br>Additionally, this value will be used as the "title" to pass to the shell on startup. Some shells (like `bash`) may choose to ignore this initial value, while others (`cmd`, `powershell`) may use this value over the lifetime of the application. This "title" behavior can be overriden by using `tabTitle`. |
 | `padding` | _Required_ | String | `0, 0, 0, 0` | Sets the padding around the text within the window. Can have three different formats: `"#"` sets the same padding for all sides, `"#, #"` sets the same padding for left-right and top-bottom, and `"#, #, #, #"` sets the padding individually for left, top, right, and bottom. |
 | `snapOnInput` | _Required_ | Boolean | `true` | When set to `true`, the window will scroll to the command input line when typing. When set to `false`, the window will not scroll when you start typing. |
 | `startingDirectory` | _Required_ | String | `%USERPROFILE%` | The directory the shell starts in when it is loaded. |
@@ -44,7 +44,7 @@ Properties listed below are specific to each unique profile.
 | `foreground` | Optional | String | | Sets the foreground color of the profile. Overrides `foreground` set in color scheme if `colorscheme` is set. Uses hex color format: `"#rrggbb"`. |
 | `icon` | Optional | String | | Image file location of the icon used in the profile. Displays within the tab and the dropdown menu. |
 | `scrollbarState` | Optional | String | | Defines the visibility of the scrollbar. Possible values: `"visible"`, `"hidden"` |
-| `tabTitle` | Optional | String | | Overrides default title of the tab. |
+| `tabTitle` | Optional | String | | If set, will replace the `name` as the title to pass to the shell on startup. Some shells (like `bash`) may choose to ignore this initial value, while others (`cmd`, `powershell`) may use this value over the lifetime of the application.  |
 
 ## Schemes
 Properties listed below are specific to each color scheme. [ColorTool](https://github.com/microsoft/terminal/tree/master/src/tools/ColorTool) is a great tool you can use to create and explore new color schemes. All colors use hex color format.

src/cascadia/TerminalApp/App.cpp

@@ -708,25 +708,12 @@ namespace winrt::TerminalApp::implementation
     void App::_UpdateTitle(std::shared_ptr<Tab> tab)
     {
         auto newTabTitle = tab->GetFocusedTitle();
-        const auto lastFocusedProfileOpt = tab->GetFocusedProfile();
-        if (lastFocusedProfileOpt.has_value())
-        {
-            const auto lastFocusedProfile = lastFocusedProfileOpt.value();
-            const auto* const matchingProfile = _settings->FindProfile(lastFocusedProfile);
-
-            const auto tabTitle = matchingProfile->GetTabTitle();
+        tab->SetTabText(newTabTitle);
 
-            // Checks if tab title has been set in the profile settings and
-            // updates accordingly.
-
-            const auto newActualTitle = tabTitle.empty() ? newTabTitle : tabTitle;
-
-            tab->SetTabText(winrt::to_hstring(newActualTitle.data()));
-            if (_settings->GlobalSettings().GetShowTitleInTitlebar() &&
-                tab->IsFocused())
-            {
-                _titleChangeHandlers(newActualTitle);
-            }
+        if (_settings->GlobalSettings().GetShowTitleInTitlebar() &&
+            tab->IsFocused())
+        {
+            _titleChangeHandlers(newTabTitle);
         }
     }
 
@@ -1456,7 +1443,12 @@ namespace winrt::TerminalApp::implementation
         }
         else
         {
-            connection = TerminalConnection::ConhostConnection(settings.Commandline(), settings.StartingDirectory(), settings.InitialRows(), settings.InitialCols(), winrt::guid());
+            connection = TerminalConnection::ConhostConnection(settings.Commandline(),
+                                                               settings.StartingDirectory(),
+                                                               settings.StartingTitle(),
+                                                               settings.InitialRows(),
+                                                               settings.InitialCols(),
+                                                               winrt::guid());
         }
 
         TraceLoggingWrite(

src/cascadia/TerminalApp/Profile.cpp

@@ -178,6 +178,10 @@ TerminalSettings Profile::CreateTerminalSettings(const std::vector<ColorScheme>&
         terminalSettings.StartingDirectory(winrt::to_hstring(evaluatedDirectory.c_str()));
     }
 
+    // GH#2373: Use the tabTitle as the starting title if it exists, otherwise
+    // use the profile name
+    terminalSettings.StartingTitle(_tabTitle ? _tabTitle.value() : _name);
+
     if (_schemeName)
     {
         const ColorScheme* const matchingScheme = _FindScheme(schemes, _schemeName.value());
@@ -594,26 +598,6 @@ std::wstring_view Profile::GetName() const noexcept
     return _name;
 }
 
-// Method Description:
-// - Returns true if profile's custom tab title is set, if one is set. Otherwise returns false.
-// Return Value:
-// - true if this profile's custom tab title is set. Otherwise returns false.
-bool Profile::HasTabTitle() const noexcept
-{
-    return _tabTitle.has_value();
-}
-
-// Method Description:
-// - Returns the custom tab title, if one is set. Otherwise returns the empty string.
-// Return Value:
-// - this profile's custom tab title, if one is set. Otherwise returns the empty string.
-std::wstring_view Profile::GetTabTitle() const noexcept
-{
-    return HasTabTitle() ?
-               std::wstring_view{ _tabTitle.value().c_str(), _tabTitle.value().size() } :
-               std::wstring_view{ L"", 0 };
-}
-
 bool Profile::HasConnectionType() const noexcept
 {
     return _connectionType.has_value();

src/cascadia/TerminalApp/Profile.h

@@ -36,8 +36,6 @@ class TerminalApp::Profile final
 
     GUID GetGuid() const noexcept;
     std::wstring_view GetName() const noexcept;
-    bool HasTabTitle() const noexcept;
-    std::wstring_view GetTabTitle() const noexcept;
     bool HasConnectionType() const noexcept;
     GUID GetConnectionType() const noexcept;
 

src/cascadia/TerminalConnection/ConhostConnection.cpp

@@ -18,13 +18,15 @@ namespace winrt::Microsoft::Terminal::TerminalConnection::implementation
 {
     ConhostConnection::ConhostConnection(const hstring& commandline,
                                          const hstring& startingDirectory,
+                                         const hstring& startingTitle,
                                          const uint32_t initialRows,
                                          const uint32_t initialCols,
                                          const guid& initialGuid) :
         _initialRows{ initialRows },
         _initialCols{ initialCols },
         _commandline{ commandline },
         _startingDirectory{ startingDirectory },
+        _startingTitle{ startingTitle },
         _guid{ initialGuid }
     {
         if (_guid == guid{})
@@ -90,6 +92,20 @@ namespace winrt::Microsoft::Terminal::TerminalConnection::implementation
 
         THROW_LAST_ERROR_IF_NULL(_hOutputThread);
 
+        STARTUPINFO si = { 0 };
+        si.cb = sizeof(STARTUPINFOW);
+
+        // If we have a startingTitle, create a mutable character buffer to add
+        // it to the STARTUPINFO.
+        std::unique_ptr<wchar_t[]> mutableTitle{ nullptr };
+        if (!_startingTitle.empty())
+        {
+            mutableTitle = std::make_unique<wchar_t[]>(_startingTitle.size() + 1);
+            THROW_IF_NULL_ALLOC(mutableTitle);
+            THROW_IF_FAILED(StringCchCopy(mutableTitle.get(), _startingTitle.size() + 1, _startingTitle.c_str()));
+            si.lpTitle = mutableTitle.get();
+        }
+
         THROW_IF_FAILED(
             CreateConPty(cmdline,
                          startingDirectory,
@@ -100,6 +116,7 @@ namespace winrt::Microsoft::Terminal::TerminalConnection::implementation
                          &_signalPipe,
                          &_piConhost,
                          0,
+                         si,
                          extraEnvVars));
 
         _connected = true;

src/cascadia/TerminalConnection/ConhostConnection.h

@@ -9,7 +9,7 @@ namespace winrt::Microsoft::Terminal::TerminalConnection::implementation
 {
     struct ConhostConnection : ConhostConnectionT<ConhostConnection>
     {
-        ConhostConnection(const hstring& cmdline, const hstring& startingDirectory, const uint32_t rows, const uint32_t cols, const guid& guid);
+        ConhostConnection(const hstring& cmdline, const hstring& startingDirectory, const hstring& startingTitle, const uint32_t rows, const uint32_t cols, const guid& guid);
 
         winrt::event_token TerminalOutput(TerminalConnection::TerminalOutputEventArgs const& handler);
         void TerminalOutput(winrt::event_token const& token) noexcept;
@@ -30,6 +30,7 @@ namespace winrt::Microsoft::Terminal::TerminalConnection::implementation
         uint32_t _initialCols{};
         hstring _commandline;
         hstring _startingDirectory;
+        hstring _startingTitle;
         guid _guid{}; // A unique session identifier for connected client
 
         bool _connected{};

src/cascadia/TerminalConnection/ConhostConnection.idl

@@ -5,10 +5,9 @@ import "ITerminalConnection.idl";
 
 namespace Microsoft.Terminal.TerminalConnection
 {
-    [default_interface]
-    runtimeclass ConhostConnection : ITerminalConnection
+    [default_interface] runtimeclass ConhostConnection : ITerminalConnection
     {
-        ConhostConnection(String cmdline, String startingDirectory, UInt32 rows, UInt32 columns, Guid guid);
+        ConhostConnection(String cmdline, String startingDirectory, String startingTitle, UInt32 rows, UInt32 columns, Guid guid);
 
         Guid Guid { get; };
     };

src/cascadia/TerminalSettings/IControlSettings.idl

@@ -22,7 +22,7 @@ namespace Microsoft.Terminal.Settings
         Boolean UseAcrylic;
         Boolean CloseOnExit;
         Double TintOpacity;
-        ScrollbarState ScrollState; 
+        ScrollbarState ScrollState;
 
         String FontFace;
         Int32 FontSize;
@@ -32,6 +32,7 @@ namespace Microsoft.Terminal.Settings
 
         String Commandline;
         String StartingDirectory;
+        String StartingTitle;
         String EnvironmentVariables;
 
         String BackgroundImage;

src/cascadia/TerminalSettings/TerminalSettings.cpp

@@ -289,6 +289,16 @@ namespace winrt::Microsoft::Terminal::Settings::implementation
         _startingDir = value;
     }
 
+    hstring TerminalSettings::StartingTitle()
+    {
+        return _startingTitle;
+    }
+
+    void TerminalSettings::StartingTitle(hstring const& value)
+    {
+        _startingTitle = value;
+    }
+
     hstring TerminalSettings::EnvironmentVariables()
     {
         return _envVars;

src/cascadia/TerminalSettings/terminalsettings.h

@@ -83,6 +83,9 @@ namespace winrt::Microsoft::Terminal::Settings::implementation
         hstring StartingDirectory();
         void StartingDirectory(hstring const& value);
 
+        hstring StartingTitle();
+        void StartingTitle(hstring const& value);
+
         hstring EnvironmentVariables();
         void EnvironmentVariables(hstring const& value);
 
@@ -115,6 +118,7 @@ namespace winrt::Microsoft::Terminal::Settings::implementation
         winrt::Windows::UI::Xaml::VerticalAlignment _backgroundImageVerticalAlignment;
         hstring _commandline;
         hstring _startingDir;
+        hstring _startingTitle;
         hstring _envVars;
         Settings::IKeyBindings _keyBindings;
         Settings::ScrollbarState _scrollbarState;

src/inc/conpty-universal.h

@@ -206,6 +206,9 @@ bool SignalResizeWindow(const HANDLE hSignal,
 // - hSignal: A handle to the pipe for writing signal messages to the pty.
 // - piPty: The PROCESS_INFORMATION of the pty process. NOTE: This is *not* the
 //      PROCESS_INFORMATION of the process that's created as a result the cmdline.
+// - startupInfo : A STARTUPINFO struct to use as additional information to pass
+//   into the created conhost process. Conhost may pass some of the properties
+//   in this struct to its child process, notably, the lpTitle.
 // - extraEnvVars : A map of pairs of (Name, Value) representing additional
 //      environment variable strings and values to be set in the client process
 //      environment.  May override any already present in parent process.
@@ -221,6 +224,7 @@ bool SignalResizeWindow(const HANDLE hSignal,
                                                                HANDLE* const hSignal,
                                                                PROCESS_INFORMATION* const piPty,
                                                                DWORD dwCreationFlags = 0,
+                                                               const STARTUPINFO startupInfo = { 0 },
                                                                const EnvironmentVariableMapW& extraEnvVars = {}) noexcept
 {
     // Create some anon pipes so we can pass handles down and into the console.
@@ -268,7 +272,7 @@ bool SignalResizeWindow(const HANDLE hSignal,
     conhostCmdline += L" -- ";
     conhostCmdline += cmdline;
 
-    STARTUPINFO si = { 0 };
+    STARTUPINFO si = startupInfo;
     si.cb = sizeof(STARTUPINFOW);
     si.hStdInput = inPipeConhostSide;
     si.hStdOutput = outPipeConhostSide;

src/server/Entrypoints.cpp

@@ -86,10 +86,14 @@
             HostStartupInfo.cb = sizeof(STARTUPINFO);
             GetStartupInfoW(&HostStartupInfo);
 
-            // If we were started with Title is Link Name, then pass the flag and the link name down to the child.
+            // Pass the title we were started with down to our child process.
+            // Conhost itself absolutely doesn't care about this value, but the
+            // child might.
+            StartupInformation.StartupInfo.lpTitle = HostStartupInfo.lpTitle;
+            // If we were started with Title is Link Name, then pass the flag
+            // down to the child. (the link name was already passed down above)
             if (WI_IsFlagSet(HostStartupInfo.dwFlags, STARTF_TITLEISLINKNAME))
             {
-                StartupInformation.StartupInfo.lpTitle = HostStartupInfo.lpTitle;
                 StartupInformation.StartupInfo.dwFlags |= STARTF_TITLEISLINKNAME;
             }
         }