Make sure titles always sanitized before passing over conpty

src/host/ConsoleArguments.cpp

@@ -667,13 +667,15 @@ bool ConsoleArguments::IsWin32InputModeEnabled() const
 #ifdef UNIT_TESTING
 // Method Description:
 // - This is a test helper method. It can be used to trick us into thinking
-//   we're headless (in conpty mode), even without parsing any arguments.
+//   we're in conpty mode, even without parsing any arguments.
 // Arguments:
 // - <none>
 // Return Value:
 // - <none>
 void ConsoleArguments::EnableConptyModeForTests()
 {
     _headless = true;
+    _vtInHandle = GetStdHandle(STD_INPUT_HANDLE);
+    _vtOutHandle = GetStdHandle(STD_OUTPUT_HANDLE);
 }
 #endif

src/host/consoleInformation.cpp

@@ -240,6 +240,20 @@ InputBuffer* const CONSOLE_INFORMATION::GetActiveInputBuffer() const
 void CONSOLE_INFORMATION::SetTitle(const std::wstring_view newTitle)
 {
     _Title = std::wstring{ newTitle.begin(), newTitle.end() };
+
+    // Sanitize the input if we're in pty mode. No control chars - this string
+    //      will get emitted back to the TTY in a VT sequence, and we don't want
+    //      to embed control characters in that string. Note that we can't use
+    //      IsInVtIoMode for this test, because the VT I/O thread won't have
+    //      been created when the title is first set during startup.
+    if (ServiceLocator::LocateGlobals().launchArgs.InConptyMode())
+    {
+        _Title.erase(std::remove_if(_Title.begin(), _Title.end(), [](auto ch) {
+                         return ch < UNICODE_SPACE || (ch > UNICODE_DEL && ch < UNICODE_NBSP);
+                     }),
+                     _Title.end());
+    }
+
     _TitleAndPrefix = _Prefix + _Title;
 
     auto* const pRender = ServiceLocator::LocateGlobals().pRender;

src/host/getset.cpp

@@ -1798,26 +1798,7 @@ void DoSrvPrivateRefreshWindow(_In_ const SCREEN_INFORMATION& screenInfo)
 [[nodiscard]] HRESULT DoSrvSetConsoleTitleW(const std::wstring_view title) noexcept
 {
     CONSOLE_INFORMATION& gci = ServiceLocator::LocateGlobals().getConsoleInformation();
-
-    // Sanitize the input if we're in pty mode. No control chars - this string
-    //      will get emitted back to the TTY in a VT sequence, and we don't want
-    //      to embed control characters in that string.
-    if (gci.IsInVtIoMode())
-    {
-        std::wstring sanitized{ title };
-        sanitized.erase(std::remove_if(sanitized.begin(), sanitized.end(), [](auto ch) {
-                            return ch < UNICODE_SPACE || (ch > UNICODE_DEL && ch < UNICODE_NBSP);
-                        }),
-                        sanitized.end());
-
-        gci.SetTitle({ sanitized });
-    }
-    else
-    {
-        // SetTitle will trigger the renderer to update the titlebar for us.
-        gci.SetTitle(title);
-    }
-
+    gci.SetTitle(title);
     return S_OK;
 }