Apply [[nodiscard]] to functions returning error codes

src/cascadia/WindowsTerminal/BaseWindow.h

@@ -16,6 +16,7 @@ class BaseWindow
         return reinterpret_cast<T *>(GetWindowLongPtr(window, GWLP_USERDATA));
     }
 
+    [[nodiscard]]
     static LRESULT __stdcall WndProc(HWND const window, UINT const message, WPARAM const wparam, LPARAM const lparam) noexcept
     {
         WINRT_ASSERT(window);
@@ -40,6 +41,7 @@ class BaseWindow
         return DefWindowProc(window, message, wparam, lparam);
     }
 
+    [[nodiscard]]
     virtual LRESULT MessageHandler(UINT const message, WPARAM const wparam, LPARAM const lparam) noexcept
     {
         switch (message) {
@@ -98,6 +100,7 @@ class BaseWindow
     }
 
     // DPI Change handler. on WM_DPICHANGE resize the window
+    [[nodiscard]]
     LRESULT HandleDpiChange(const HWND hWnd, const WPARAM wParam, const LPARAM lParam)
     {
         _inDpiChange = true;

src/cascadia/WindowsTerminal/IslandWindow.cpp

@@ -144,6 +144,7 @@ void IslandWindow::OnSize()
     }
 }
 
+[[nodiscard]]
 LRESULT IslandWindow::MessageHandler(UINT const message, WPARAM const wparam, LPARAM const lparam) noexcept
 {
     switch (message) {
@@ -173,7 +174,7 @@ LRESULT IslandWindow::MessageHandler(UINT const message, WPARAM const wparam, LP
 // Arguments:
 // - width: the new width of the window _in pixels_
 // - height: the new height of the window _in pixels_
-void IslandWindow::OnResize(const UINT width, const UINT height)
+void IslandWindow::OnResize(const UINT /*width*/, const UINT /*height*/)
 {
     OnSize();
 }

src/cascadia/WindowsTerminal/IslandWindow.h

@@ -16,6 +16,7 @@ class IslandWindow : public BaseWindow<IslandWindow>
     void Close();
     virtual void OnSize();
 
+    [[nodiscard]]
     virtual LRESULT MessageHandler(UINT const message, WPARAM const wparam, LPARAM const lparam) noexcept override;
     void OnResize(const UINT width, const UINT height) override;
     void OnMinimize() override;

src/cascadia/WindowsTerminal/NonClientIslandWindow.cpp

@@ -209,6 +209,7 @@ void NonClientIslandWindow::OnSize()
 // NOTE:
 // Largely taken from code on:
 // https://docs.microsoft.com/en-us/windows/desktop/dwm/customframe
+[[nodiscard]]
 LRESULT NonClientIslandWindow::HitTestNCA(POINT ptMouse) const noexcept
 {
     // Get the window rectangle.
@@ -284,6 +285,7 @@ MARGINS NonClientIslandWindow::GetFrameMargins() const noexcept
 // - <none>
 // Return Value:
 // - the HRESULT returned by DwmExtendFrameIntoClientArea.
+[[nodiscard]]
 HRESULT NonClientIslandWindow::_UpdateFrameMargins() const noexcept
 {
     // Get the size of the borders we want to use. The sides and bottom will
@@ -387,6 +389,7 @@ RECT NonClientIslandWindow::GetMaxWindowRectInPixels(const RECT * const prcSugge
 // Return Value:
 // - The return value is the result of the message processing and depends on the
 //   message sent.
+[[nodiscard]]
 LRESULT NonClientIslandWindow::MessageHandler(UINT const message,
                                               WPARAM const wParam,
                                               LPARAM const lParam) noexcept
@@ -489,7 +492,7 @@ void NonClientIslandWindow::_HandleActivateWindow()
     // _titlebarUnscaledContentHeight is set with SetNonClientHeight by the app
     // hosting us.
 
-    _UpdateFrameMargins();
+    THROW_IF_FAILED(_UpdateFrameMargins());
 }
 
 // Method Description:
@@ -633,7 +636,7 @@ bool NonClientIslandWindow::_HandleWindowPosChanging(WINDOWPOS* const windowPos)
             _maximizedMargins.cyBottomHeight = -offset;
 
             _isMaximized = true;
-            _UpdateFrameMargins();
+            THROW_IF_FAILED(_UpdateFrameMargins());
         }
     }
     else
@@ -647,7 +650,7 @@ bool NonClientIslandWindow::_HandleWindowPosChanging(WINDOWPOS* const windowPos)
         // keep this here _in general_ for dragging across DPI boundaries.
         if (!_isMaximized)
         {
-            _UpdateFrameMargins();
+            THROW_IF_FAILED(_UpdateFrameMargins());
         }
 
         _isMaximized = false;

src/cascadia/WindowsTerminal/NonClientIslandWindow.h

@@ -31,6 +31,7 @@ class NonClientIslandWindow : public IslandWindow
 
     virtual void OnSize() override;
 
+    [[nodiscard]]
     virtual LRESULT MessageHandler(UINT const message, WPARAM const wparam, LPARAM const lparam) noexcept override;
 
     void SetNonClientContent(winrt::Windows::UI::Xaml::UIElement content);
@@ -62,7 +63,10 @@ class NonClientIslandWindow : public IslandWindow
     MARGINS _maximizedMargins;
     bool _isMaximized;
 
+    [[nodiscard]]
     LRESULT HitTestNCA(POINT ptMouse) const noexcept;
+
+    [[nodiscard]]
     HRESULT _UpdateFrameMargins() const noexcept;
 
     void _HandleActivateWindow();

src/host/ConsoleArguments.hpp

@@ -32,7 +32,6 @@ class ConsoleArguments
     [[nodiscard]]
     HRESULT ParseCommandline();
 
-    bool IsUsingVtPipe() const;
     bool HasVtHandles() const;
     bool InConptyMode() const noexcept;
     bool IsHeadless() const;

src/host/VtIo.cpp

@@ -105,7 +105,7 @@ HRESULT VtIo::Initialize(const ConsoleArguments * const pArgs)
 //  S_OK if we initialized successfully, otherwise an appropriate HRESULT
 //      indicating failure.
 [[nodiscard]]
-HRESULT VtIo::_Initialize(const HANDLE InHandle, const HANDLE OutHandle, const std::wstring& VtMode, const HANDLE SignalHandle)
+HRESULT VtIo::_Initialize(const HANDLE InHandle, const HANDLE OutHandle, const std::wstring& VtMode, _In_opt_ const HANDLE SignalHandle)
 {
     FAIL_FAST_IF_MSG(_initialized, "Someone attempted to double-_Initialize VtIo");
 

src/host/VtIo.hpp

@@ -63,9 +63,7 @@ namespace Microsoft::Console::VirtualTerminal
         std::unique_ptr<Microsoft::Console::PtySignalInputThread> _pPtySignalInputThread;
 
         [[nodiscard]]
-        HRESULT _Initialize(const HANDLE InHandle, const HANDLE OutHandle, const std::wstring& VtMode);
-        [[nodiscard]]
-        HRESULT _Initialize(const HANDLE InHandle, const HANDLE OutHandle, const std::wstring& VtMode, _In_opt_ HANDLE SignalHandle);
+        HRESULT _Initialize(const HANDLE InHandle, const HANDLE OutHandle, const std::wstring& VtMode, _In_opt_ const HANDLE SignalHandle);
 
         void _ShutdownIfNeeded();
 

src/host/cmdline.h

@@ -158,7 +158,7 @@ void RedrawCommandLine(COOKED_READ_DATA& cookedReadData);
 #define WC_DELAY_EOL_WRAP        0x80
 
 // Word delimiters
-bool IsWordDelim(const WCHAR wch);
+bool IsWordDelim(const wchar_t wch);
 bool IsWordDelim(const std::wstring_view charData);
 
 [[nodiscard]]

src/host/popup.cpp

@@ -333,6 +333,7 @@ void Popup::SetUserInputFunction(UserInputFunction function) noexcept
 // - wch - on completion, the char read from the user
 // Return Value:
 // - relevant NTSTATUS
+[[nodiscard]]
 NTSTATUS Popup::_getUserInput(COOKED_READ_DATA& cookedReadData, bool& popupKey, DWORD& modifiers, wchar_t& wch) noexcept
 {
     return _userInputFunction(cookedReadData, popupKey, modifiers, wch);
@@ -346,6 +347,7 @@ NTSTATUS Popup::_getUserInput(COOKED_READ_DATA& cookedReadData, bool& popupKey,
 // - wch - on completion, the char read from the user
 // Return Value:
 // - relevant NTSTATUS
+[[nodiscard]]
 NTSTATUS Popup::_getUserInputInternal(COOKED_READ_DATA& cookedReadData,
                                       bool& popupKey,
                                       DWORD& modifiers,

src/host/popup.h

@@ -66,6 +66,7 @@ class Popup
     friend class CommandListPopupTests;
 #endif
 
+    [[nodiscard]]
     NTSTATUS _getUserInput(COOKED_READ_DATA& cookedReadData, bool& popupKey, DWORD& modifiers, wchar_t& wch) noexcept;
     void _DrawPrompt(const UINT id);
     virtual void _DrawContent() = 0;
@@ -81,6 +82,7 @@ class Popup
 
     void _DrawBorder();
 
+    [[nodiscard]]
     static NTSTATUS _getUserInputInternal(COOKED_READ_DATA& cookedReadData,
                                           bool& popupKey,
                                           DWORD& modifiers,

src/inc/test/CommonState.hpp

@@ -222,6 +222,7 @@ class CommonState
         textBuffer.GetCursor().SetYPosition(cRowsToFill);
     }
 
+    [[nodiscard]]
     NTSTATUS GetTextBufferInfoInitResult()
     {
         return m_ntstatusTextBufferInfo;

src/interactivity/inc/IConsoleControl.hpp

@@ -21,8 +21,11 @@ namespace Microsoft::Console::Interactivity
     {
     public:
         virtual ~IConsoleControl() = 0;
+        [[nodiscard]]
         virtual NTSTATUS NotifyConsoleApplication(DWORD dwProcessId) = 0;
+        [[nodiscard]]
         virtual NTSTATUS SetForeground(HANDLE hProcess, BOOL fForeground) = 0;
+        [[nodiscard]]
         virtual NTSTATUS EndTask(HANDLE hProcessId, DWORD dwEventType, ULONG ulCtrlFlags) = 0;
 
     protected:

src/interactivity/win32/window.cpp

@@ -1191,6 +1191,7 @@ void Window::s_ReinitializeFontsForDPIChange()
     gci.GetActiveOutputBuffer().RefreshFontWithRenderer();
 }
 
+[[nodiscard]]
 LRESULT Window::s_RegPersistWindowPos(_In_ PCWSTR const pwszTitle,
                                       const BOOL fAutoPos,
                                       const Window* const pWindow)
@@ -1257,6 +1258,7 @@ LRESULT Window::s_RegPersistWindowPos(_In_ PCWSTR const pwszTitle,
     return Status;
 }
 
+[[nodiscard]]
 LRESULT Window::s_RegPersistWindowOpacity(_In_ PCWSTR const pwszTitle, const Window* const pWindow)
 {
     HKEY hCurrentUserKey, hConsoleKey, hTitleKey;

src/interactivity/win32/window.hpp

@@ -121,10 +121,12 @@ namespace Microsoft::Console::Interactivity::Win32
         void _UpdateSystemMetrics() const;
 
         // Wndproc
+        [[nodiscard]]
         static LRESULT CALLBACK s_ConsoleWindowProc(_In_ HWND hwnd,
                                                     _In_ UINT uMsg,
                                                     _In_ WPARAM wParam,
                                                     _In_ LPARAM lParam);
+        [[nodiscard]]
         LRESULT CALLBACK ConsoleWindowProc(_In_ HWND,
                                             _In_ UINT uMsg,
                                             _In_ WPARAM wParam,
@@ -137,16 +139,19 @@ namespace Microsoft::Console::Interactivity::Win32
         void _HandleWindowPosChanged(const LPARAM lParam);
 
         // Accessibility/UI Automation
+        [[nodiscard]]
         LRESULT _HandleGetObject(const HWND hwnd,
                                     const WPARAM wParam,
                                     const LPARAM lParam);
         IRawElementProviderSimple* _GetUiaProvider();
         WindowUiaProvider* _pUiaProvider = nullptr;
 
         // Dynamic Settings helpers
+        [[nodiscard]]
         static LRESULT s_RegPersistWindowPos(_In_ PCWSTR const pwszTitle,
                                                 const BOOL fAutoPos,
                                                 const Window* const pWindow);
+        [[nodiscard]]
         static LRESULT s_RegPersistWindowOpacity(_In_ PCWSTR const pwszTitle,
                                                     const Window* const pWindow);
 

src/interactivity/win32/windowproc.cpp

@@ -39,6 +39,7 @@ using namespace Microsoft::Console::Types;
 // The static and specific window procedures for this class are contained here
 #pragma region Window Procedure
 
+[[nodiscard]]
 LRESULT CALLBACK Window::s_ConsoleWindowProc(_In_ HWND hWnd, _In_ UINT Message, _In_ WPARAM wParam, _In_ LPARAM lParam)
 {
     // Save the pointer here to the specific window instance when one is created
@@ -61,6 +62,7 @@ LRESULT CALLBACK Window::s_ConsoleWindowProc(_In_ HWND hWnd, _In_ UINT Message,
     return DefWindowProcW(hWnd, Message, wParam, lParam);
 }
 
+[[nodiscard]]
 LRESULT CALLBACK Window::ConsoleWindowProc(_In_ HWND hWnd, _In_ UINT Message, _In_ WPARAM wParam, _In_ LPARAM lParam)
 {
     Globals& g = ServiceLocator::LocateGlobals();
@@ -886,6 +888,7 @@ void Window::_HandleDrop(const WPARAM wParam) const
     }
 }
 
+[[nodiscard]]
 LRESULT Window::_HandleGetObject(const HWND hwnd, const WPARAM wParam, const LPARAM lParam)
 {
     LRESULT retVal = 0;

src/propsheet/ColorControl.cpp

@@ -42,6 +42,7 @@ void SimpleColorDoPaint(const HWND hColor, PAINTSTRUCT& ps, const int ColorId)
 
 // Routine Description:
 // - Window proc for the color buttons
+[[nodiscard]]
 LRESULT CALLBACK SimpleColorControlProc(const HWND hColor, const UINT wMsg, const WPARAM wParam, const LPARAM lParam)
 {
     PAINTSTRUCT ps;

src/propsheet/ColorControl.h

@@ -14,5 +14,6 @@ Author(s):
 
 #pragma once
 
+[[nodiscard]]
 LRESULT CALLBACK SimpleColorControlProc(HWND hColor, UINT wMsg, WPARAM wParam, LPARAM lParam);
 void SimpleColorDoPaint(HWND hColor, PAINTSTRUCT& ps, int ColorId);

src/propsheet/ColorsPage.cpp

@@ -10,6 +10,7 @@ static int iColor;
 
 // Routine Description:
 // - Window proc for the color buttons
+[[nodiscard]]
 LRESULT CALLBACK ColorTableControlProc(HWND hColor, UINT wMsg, WPARAM wParam, LPARAM lParam)
 {
     PAINTSTRUCT ps;

src/propsheet/ColorsPage.h

@@ -18,4 +18,5 @@ void ToggleV2ColorControls(__in const HWND hDlg);
 INT_PTR WINAPI ColorDlgProc(HWND hDlg, UINT wMsg, WPARAM wParam, LPARAM lParam);
 void SetOpacitySlider(__in HWND hDlg);
 void PreviewOpacity(HWND hDlg, BYTE bOpacity);
+[[nodiscard]]
 LRESULT CALLBACK ColorTableControlProc(HWND hColor, UINT wMsg, WPARAM wParam, LPARAM lParam);

src/propsheet/console.cpp

@@ -702,6 +702,7 @@ void UnregisterClasses(HINSTANCE hModule)
     UnregisterClass(TEXT("WOAFontPreview"), hModule);
 }
 
+[[nodiscard]]
 HRESULT FindFontAndUpdateState()
 {
     g_currentFontIndex = FindCreateFont(gpStateInfo->FontFamily,

src/propsheet/console.h

@@ -58,15 +58,16 @@ Revision History:
 #define IDS_TOOLTIP_OPACITY          17
 #define IDS_TOOLTIP_INTERCEPT_COPY_PASTE    18
 
-NTSTATUS
+void
 MakeAltRasterFont(
     __in UINT CodePage,
     __out COORD *AltFontSize,
     __out BYTE  *AltFontFamily,
     __out ULONG *AltFontIndex,
     __out_ecount(LF_FACESIZE) LPTSTR AltFaceName);
 
-NTSTATUS InitializeDbcsMisc();
+[[nodiscard]]
+NTSTATUS InitializeDbcsMisc(VOID);
 
 BYTE
 CodePageToCharSet(
@@ -104,7 +105,7 @@ GetAltFaceName(
     LPCTSTR ptszFace
     );
 
-NTSTATUS DestroyDbcsMisc();
+NTSTATUS DestroyDbcsMisc(VOID);
 
 int
 LanguageListCreate(
@@ -170,15 +171,14 @@ VOID SetRegistryValues(
     PCONSOLE_STATE_INFO StateInfo,
     DWORD dwPage);
 
-PCONSOLE_STATE_INFO InitStateValues(
-    HWND hwnd);
-
+[[nodiscard]]
 LRESULT CALLBACK FontPreviewWndProc(
     HWND hWnd,
     UINT wMsg,
     WPARAM wParam,
     LPARAM lParam);
 
+[[nodiscard]]
 LRESULT CALLBACK PreviewWndProc(
     HWND hWnd,
     UINT wMsg,
@@ -197,6 +197,7 @@ BOOL UpdateStateInfo(
 BOOL InitializeConsoleState();
 void UninitializeConsoleState();
 void UpdateApplyButton(const HWND hDlg);
+[[nodiscard]]
 HRESULT FindFontAndUpdateState();
 
 BOOL PopulatePropSheetPageArray(_Out_writes_(cPsps) PROPSHEETPAGE *pPsp, const size_t cPsps, const BOOL fRegisterCallbacks);