Add settings to warn about large or multiline pastes

.github/actions/spell-check/dictionary/apis.txt

@@ -13,6 +13,7 @@ IBind
 IClass
 IComparable
 ICustom
+IDialog
 IDirect
 IExplorer
 IMap

doc/cascadia/SettingsSchema.md

@@ -9,6 +9,8 @@ Properties listed below affect the entire window, regardless of the profile sett
 | `alwaysShowTabs` | _Required_ | Boolean | `true` | When set to `true`, tabs are always displayed. When set to `false` and `showTabsInTitlebar` is set to `false`, tabs only appear after typing <kbd>Ctrl</kbd> + <kbd>T</kbd>. |
 | `copyOnSelect` | Optional | Boolean | `false` | When set to `true`, a selection is immediately copied to your clipboard upon creation. When set to `false`, the selection persists and awaits further action. |
 | `copyFormatting` | Optional | Boolean | `false` | When set to `true`, the color and font formatting of selected text is also copied to your clipboard. When set to `false`, only plain text is copied to your clipboard. |
+| `largePasteWarning` | Optional | Boolean | `true` | When set to `true`, trying to paste text with more than 5 KiB of characters will display a warning asking you whether to continue or not with the paste. |
+| `multiLinePasteWarning` | Optional | Boolean | `true` | When set to `true`, trying to paste text with a _new line_ character will display a warning asking you whether to continue or not with the paste. |
 | `defaultProfile` | _Required_ | String | PowerShell guid | Sets the default profile. Opens by typing <kbd>Ctrl</kbd> + <kbd>T</kbd> or by clicking the '+' icon. The guid of the desired default profile is used as the value. |
 | `initialCols` | _Required_ | Integer | `120` | The number of columns displayed in the window upon first load. |
 | `initialPosition` | Optional | String | `","` | The position of the top left corner of the window upon first load. On a system with multiple displays, these coordinates are relative to the top left of the primary display. If `launchMode` is set to `"maximized"`, the window will be maximized on the monitor specified by those coordinates. |

doc/cascadia/profiles.schema.json

@@ -316,6 +316,16 @@
           "description": "When set to `true`, the color and font formatting of selected text is also copied to your clipboard. When set to `false`, only plain text is copied to your clipboard.",
           "type": "boolean"
         },
+        "largePasteWarning": {
+          "default": true,
+          "description": "When set to true, trying to paste text with more than 5 KiB of characters will display a warning asking you whether to continue or not with the paste.",
+          "type": "boolean"
+        },
+        "multiLinePasteWarning": {
+          "default": true,
+          "description": "When set to true, trying to paste text with a \"new line\" character will display a warning asking you whether to continue or not with the paste.",
+          "type": "boolean"
+        },
         "defaultProfile": {
           "description": "Sets the default profile. Opens by clicking the \"+\" icon or typing the key binding assigned to \"newTab\".",
           "type": "string"

src/cascadia/TerminalApp/AppLogic.cpp

@@ -11,6 +11,7 @@
 using namespace winrt::Windows::ApplicationModel;
 using namespace winrt::Windows::ApplicationModel::DataTransfer;
 using namespace winrt::Windows::UI::Xaml;
+using namespace winrt::Windows::UI::Xaml::Controls;
 using namespace winrt::Windows::UI::Core;
 using namespace winrt::Windows::System;
 using namespace winrt::Microsoft::Terminal;
@@ -231,7 +232,7 @@ namespace winrt::TerminalApp::implementation
         // this as a MTA, before the app is Create()'d
         WINRT_ASSERT(_loadedInitialSettings);
 
-        _root->ShowDialog({ this, &AppLogic::_ShowDialog });
+        _root->DialogPresenter(*this);
 
         // In UWP mode, we cannot handle taking over the title bar for tabs,
         // so this setting is overridden to false no matter what the preference is.
@@ -277,17 +278,18 @@ namespace winrt::TerminalApp::implementation
     // - Only one dialog can be visible at a time. If another dialog is visible
     //   when this is called, nothing happens.
     // Arguments:
-    // sender: unused
-    // dialog: the dialog object that is going to show up
-    fire_and_forget AppLogic::_ShowDialog(const winrt::Windows::Foundation::IInspectable& sender, winrt::Windows::UI::Xaml::Controls::ContentDialog dialog)
+    // - dialog: the dialog object that is going to show up
+    // Return value:
+    // - an IAsyncOperation with the dialog result
+    winrt::Windows::Foundation::IAsyncOperation<ContentDialogResult> AppLogic::ShowDialog(winrt::Windows::UI::Xaml::Controls::ContentDialog dialog)
     {
         // DON'T release this lock in a wil::scope_exit. The scope_exit will get
         // called when we await, which is not what we want.
         std::unique_lock lock{ _dialogLock, std::try_to_lock };
         if (!lock)
         {
             // Another dialog is visible.
-            return;
+            co_return ContentDialogResult::None;
         }
 
         // IMPORTANT: This is necessary as documented in the ContentDialog MSDN docs.
@@ -321,7 +323,7 @@ namespace winrt::TerminalApp::implementation
         auto loadedRevoker{ dialog.Loaded(winrt::auto_revoke, themingLambda) }; // if it's not yet in the tree
 
         // Display the dialog.
-        co_await dialog.ShowAsync(Controls::ContentDialogPlacement::Popup);
+        return co_await dialog.ShowAsync(Controls::ContentDialogPlacement::Popup);
 
         // After the dialog is dismissed, the dialog lock (held by `lock`) will
         // be released so another can be shown
@@ -333,7 +335,7 @@ namespace winrt::TerminalApp::implementation
     //   as the title and first content of the dialog, then also displays a
     //   message for whatever exception was found while validating the settings.
     // - Only one dialog can be visible at a time. If another dialog is visible
-    //   when this is called, nothing happens. See _ShowDialog for details
+    //   when this is called, nothing happens. See ShowDialog for details
     // Arguments:
     // - titleKey: The key to use to lookup the title text from our resources.
     // - contentKey: The key to use to lookup the content text from our resources.
@@ -378,15 +380,15 @@ namespace winrt::TerminalApp::implementation
         dialog.CloseButtonText(buttonText);
         dialog.DefaultButton(Controls::ContentDialogButton::Close);
 
-        _ShowDialog(nullptr, dialog);
+        ShowDialog(dialog);
     }
 
     // Method Description:
     // - Displays a dialog for warnings found while loading or validating the
     //   settings. Displays messages for whatever warnings were found while
     //   validating the settings.
     // - Only one dialog can be visible at a time. If another dialog is visible
-    //   when this is called, nothing happens. See _ShowDialog for details
+    //   when this is called, nothing happens. See ShowDialog for details
     void AppLogic::_ShowLoadWarningsDialog()
     {
         auto title = RS_(L"SettingsValidateErrorTitle");
@@ -437,7 +439,7 @@ namespace winrt::TerminalApp::implementation
         dialog.CloseButtonText(buttonText);
         dialog.DefaultButton(Controls::ContentDialogButton::Close);
 
-        _ShowDialog(nullptr, dialog);
+        ShowDialog(dialog);
     }
 
     // Method Description:

src/cascadia/TerminalApp/AppLogic.h

@@ -49,6 +49,8 @@ namespace winrt::TerminalApp::implementation
 
         void WindowCloseButtonClicked();
 
+        winrt::Windows::Foundation::IAsyncOperation<winrt::Windows::UI::Xaml::Controls::ContentDialogResult> ShowDialog(winrt::Windows::UI::Xaml::Controls::ContentDialog dialog);
+
         // -------------------------------- WinRT Events ---------------------------------
         DECLARE_EVENT_WITH_TYPED_EVENT_HANDLER(RequestedThemeChanged, _requestedThemeChangedHandlers, winrt::Windows::Foundation::IInspectable, winrt::Windows::UI::Xaml::ElementTheme);
 
@@ -79,7 +81,6 @@ namespace winrt::TerminalApp::implementation
         ::TerminalApp::AppCommandlineArgs _appArgs;
         int _ParseArgs(winrt::array_view<const hstring>& args);
 
-        fire_and_forget _ShowDialog(const winrt::Windows::Foundation::IInspectable& sender, winrt::Windows::UI::Xaml::Controls::ContentDialog dialog);
         void _ShowLoadErrorsDialog(const winrt::hstring& titleKey, const winrt::hstring& contentKey, HRESULT settingsLoadedResult);
         void _ShowLoadWarningsDialog();
 

src/cascadia/TerminalApp/AppLogic.idl

@@ -14,7 +14,7 @@ namespace TerminalApp
         FullscreenMode,
     };
 
-    [default_interface] runtimeclass AppLogic : IDirectKeyListener
+    [default_interface] runtimeclass AppLogic : IDirectKeyListener, IDialogPresenter
     {
         AppLogic();
 
@@ -50,6 +50,10 @@ namespace TerminalApp
         void TitlebarClicked();
         void WindowCloseButtonClicked();
 
+        // See IDialogPresenter and TerminalPage's DialogPresenter for more
+        // information.
+        Windows.Foundation.IAsyncOperation<Windows.UI.Xaml.Controls.ContentDialogResult> ShowDialog(Windows.UI.Xaml.Controls.ContentDialog dialog);
+
         event Windows.Foundation.TypedEventHandler<Object, Windows.UI.Xaml.UIElement> SetTitleBarContent;
         event Windows.Foundation.TypedEventHandler<Object, String> TitleChanged;
         event Windows.Foundation.TypedEventHandler<Object, LastTabClosedEventArgs> LastTabClosed;

src/cascadia/TerminalApp/GlobalAppSettings.cpp

@@ -31,6 +31,8 @@ static constexpr std::string_view ShowTabsInTitlebarKey{ "showTabsInTitlebar" };
 static constexpr std::string_view WordDelimitersKey{ "wordDelimiters" };
 static constexpr std::string_view CopyOnSelectKey{ "copyOnSelect" };
 static constexpr std::string_view CopyFormattingKey{ "copyFormatting" };
+static constexpr std::string_view WarnAboutLargePasteKey{ "largePasteWarning" };
+static constexpr std::string_view WarnAboutMultiLinePasteKey{ "multiLinePasteWarning" };
 static constexpr std::string_view LaunchModeKey{ "launchMode" };
 static constexpr std::string_view ConfirmCloseAllKey{ "confirmCloseAllTabs" };
 static constexpr std::string_view SnapToGridOnResizeKey{ "snapToGridOnResize" };
@@ -190,6 +192,10 @@ void GlobalAppSettings::LayerJson(const Json::Value& json)
 
     JsonUtils::GetBool(json, CopyFormattingKey, _CopyFormatting);
 
+    JsonUtils::GetBool(json, WarnAboutLargePasteKey, _WarnAboutLargePaste);
+
+    JsonUtils::GetBool(json, WarnAboutMultiLinePasteKey, _WarnAboutMultiLinePaste);
+
     if (auto launchMode{ json[JsonKey(LaunchModeKey)] })
     {
         _LaunchMode = _ParseLaunchMode(GetWstringFromJson(launchMode));

src/cascadia/TerminalApp/GlobalAppSettings.h

@@ -72,6 +72,8 @@ class TerminalApp::GlobalAppSettings final
     GETSET_PROPERTY(std::wstring, WordDelimiters); // default value set in constructor
     GETSET_PROPERTY(bool, CopyOnSelect, false);
     GETSET_PROPERTY(bool, CopyFormatting, false);
+    GETSET_PROPERTY(bool, WarnAboutLargePaste, true);
+    GETSET_PROPERTY(bool, WarnAboutMultiLinePaste, true);
     GETSET_PROPERTY(LaunchPosition, InitialPosition);
     GETSET_PROPERTY(winrt::TerminalApp::LaunchMode, LaunchMode, winrt::TerminalApp::LaunchMode::DefaultMode);
     GETSET_PROPERTY(bool, SnapToGridOnResize, true);

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

@@ -347,4 +347,28 @@
     <value>Command Prompt</value>
     <comment>This is the name of "Command Prompt", as localized in Windows. The localization here should match the one in the Windows product for "Command Prompt"</comment>
   </data>
+  <data name="LargePasteDialog.CloseButtonText" xml:space="preserve">
+    <value>Cancel</value>
+  </data>
+  <data name="LargePasteDialog.Content" xml:space="preserve">
+    <value>You are about to paste text that is longer than 5 KiB. This can make the terminal unresponsive while the text is being received on the other end. Are you sure you want to continue?</value>
+  </data>
+  <data name="LargePasteDialog.PrimaryButtonText" xml:space="preserve">
+    <value>Paste anyway</value>
+  </data>
+  <data name="LargePasteDialog.Title" xml:space="preserve">
+    <value>Warning</value>
+  </data>
+  <data name="MultiLinePasteDialog.CloseButtonText" xml:space="preserve">
+    <value>Cancel</value>
+  </data>
+  <data name="MultiLinePasteDialog.Content" xml:space="preserve">
+    <value>You are about to paste text that contains the "new line" character. If you paste text that contains the "new line" character into a shell, one or more command(s) will be executed automatically upon paste. Are you sure you want to continue?</value>
+  </data>
+  <data name="MultiLinePasteDialog.PrimaryButtonText" xml:space="preserve">
+    <value>Paste anyway</value>
+  </data>
+  <data name="MultiLinePasteDialog.Title" xml:space="preserve">
+    <value>Warning</value>
+  </data>
 </root>

src/cascadia/TerminalApp/TerminalPage.cpp

@@ -23,6 +23,7 @@
 using namespace winrt;
 using namespace winrt::Windows::Foundation::Collections;
 using namespace winrt::Windows::UI::Xaml;
+using namespace winrt::Windows::UI::Xaml::Controls;
 using namespace winrt::Windows::UI::Core;
 using namespace winrt::Windows::System;
 using namespace winrt::Windows::ApplicationModel::DataTransfer;
@@ -246,7 +247,10 @@ namespace winrt::TerminalApp::implementation
     //   Notes link, and privacy policy link.
     void TerminalPage::_ShowAboutDialog()
     {
-        _showDialogHandlers(*this, FindName(L"AboutDialog").try_as<WUX::Controls::ContentDialog>());
+        if (auto presenter{ _dialogPresenter.get() })
+        {
+            presenter.ShowDialog(FindName(L"AboutDialog").try_as<WUX::Controls::ContentDialog>());
+        }
     }
 
     winrt::hstring TerminalPage::ApplicationDisplayName()
@@ -285,7 +289,42 @@ namespace winrt::TerminalApp::implementation
     //   when this is called, nothing happens. See _ShowDialog for details
     void TerminalPage::_ShowCloseWarningDialog()
     {
-        _showDialogHandlers(*this, FindName(L"CloseAllDialog").try_as<WUX::Controls::ContentDialog>());
+        if (auto presenter{ _dialogPresenter.get() })
+        {
+            presenter.ShowDialog(FindName(L"CloseAllDialog").try_as<WUX::Controls::ContentDialog>());
+        }
+    }
+
+    // Method Description:
+    // - Displays a dialog to warn the user about the fact that the text that
+    //   they are trying to paste contains the "new line" character which can
+    //   have the effect of starting commands without the user's knowledge if
+    //   it is pasted on a shell where the "new line" character marks the end
+    //   of a command.
+    // - Only one dialog can be visible at a time. If another dialog is visible
+    //   when this is called, nothing happens. See _ShowDialog for details
+    winrt::Windows::Foundation::IAsyncOperation<ContentDialogResult> TerminalPage::_ShowMultiLinePasteWarningDialog()
+    {
+        if (auto presenter{ _dialogPresenter.get() })
+        {
+            co_return co_await presenter.ShowDialog(FindName(L"MultiLinePasteDialog").try_as<WUX::Controls::ContentDialog>());
+        }
+        co_return ContentDialogResult::None;
+    }
+
+    // Method Description:
+    // - Displays a dialog to warn the user about the fact that the text that
+    //   they are trying to paste is very long, in case they did not mean to
+    //   paste it but pressed the paste shortcut by accident.
+    // - Only one dialog can be visible at a time. If another dialog is visible
+    //   when this is called, nothing happens. See _ShowDialog for details
+    winrt::Windows::Foundation::IAsyncOperation<ContentDialogResult> TerminalPage::_ShowLargePasteWarningDialog()
+    {
+        if (auto presenter{ _dialogPresenter.get() })
+        {
+            co_return co_await presenter.ShowDialog(FindName(L"LargePasteWarningDialog").try_as<WUX::Controls::ContentDialog>());
+        }
+        co_return ContentDialogResult::None;
     }
 
     // Method Description:
@@ -1472,26 +1511,19 @@ namespace winrt::TerminalApp::implementation
         CATCH_LOG();
     }
 
-    // Method Description:
-    // - Fires an async event to get data from the clipboard, and paste it to
-    //   the terminal. Triggered when the Terminal Control requests clipboard
-    //   data with it's PasteFromClipboard event.
-    // Arguments:
-    // - eventArgs: the PasteFromClipboard event sent from the TermControl
-    winrt::fire_and_forget TerminalPage::_PasteFromClipboardHandler(const IInspectable /*sender*/,
-                                                                    const PasteFromClipboardEventArgs eventArgs)
-    {
-        co_await winrt::resume_foreground(Dispatcher(), CoreDispatcherPriority::High);
-
-        TerminalPage::PasteFromClipboard(eventArgs);
-    }
-
     // Function Description:
-    // - Copies and processes the text data from the Windows Clipboard.
-    //   Does some of this in a background thread, as to not hang/crash the UI thread.
+    // - This function is called when the `TermControl` requests that we send
+    //   it the clipboard's content.
+    // - Retrieves the data from the Windows Clipboard and converts it to text.
+    // - Shows warnings if the clipboard is too big or contains multiple lines
+    //   of text.
+    // - Sends the text back to the TermControl through the event's
+    //   `HandleClipboardData` member function.
+    // - Does some of this in a background thread, as to not hang/crash the UI thread.
     // Arguments:
     // - eventArgs: the PasteFromClipboard event sent from the TermControl
-    fire_and_forget TerminalPage::PasteFromClipboard(PasteFromClipboardEventArgs eventArgs)
+    fire_and_forget TerminalPage::_PasteFromClipboardHandler(const IInspectable /*sender*/,
+                                                             const PasteFromClipboardEventArgs eventArgs)
     {
         const DataPackageView data = Clipboard::GetContent();
 
@@ -1517,6 +1549,32 @@ namespace winrt::TerminalApp::implementation
                     text = item.Path();
                 }
             }
+
+            co_await winrt::resume_foreground(Dispatcher());
+
+            const bool hasNewLine = std::find(text.cbegin(), text.cend(), L'\n') != text.cend();
+            const bool warnMultiLine = hasNewLine && _settings->GlobalSettings().WarnAboutMultiLinePaste();
+
+            constexpr const std::size_t minimumSizeForWarning = 1024 * 5; // 5 KiB
+            const bool warnLargeText = text.size() > minimumSizeForWarning &&
+                                       _settings->GlobalSettings().WarnAboutLargePaste();
+
+            ContentDialogResult warningResult = ContentDialogResult::Primary;
+            if (warnMultiLine)
+            {
+                warningResult = co_await _ShowMultiLinePasteWarningDialog();
+            }
+            else if (warnLargeText)
+            {
+                warningResult = co_await _ShowLargePasteWarningDialog();
+            }
+
+            if (warningResult != ContentDialogResult::Primary)
+            {
+                // user rejected the paste
+                co_return;
+            }
+
             eventArgs.HandleClipboardData(text);
         }
         CATCH_LOG();
@@ -1793,6 +1851,16 @@ namespace winrt::TerminalApp::implementation
         _startupActions = actions;
     }
 
+    winrt::TerminalApp::IDialogPresenter TerminalPage::DialogPresenter() const
+    {
+        return _dialogPresenter.get();
+    }
+
+    void TerminalPage::DialogPresenter(winrt::TerminalApp::IDialogPresenter dialogPresenter)
+    {
+        _dialogPresenter = dialogPresenter;
+    }
+
     // Method Description:
     // - This is the method that App will call when the titlebar
     //   has been clicked. It dismisses any open flyouts.
@@ -2022,6 +2090,5 @@ namespace winrt::TerminalApp::implementation
     DEFINE_EVENT_WITH_TYPED_EVENT_HANDLER(TerminalPage, TitleChanged, _titleChangeHandlers, winrt::Windows::Foundation::IInspectable, winrt::hstring);
     DEFINE_EVENT_WITH_TYPED_EVENT_HANDLER(TerminalPage, LastTabClosed, _lastTabClosedHandlers, winrt::Windows::Foundation::IInspectable, winrt::TerminalApp::LastTabClosedEventArgs);
     DEFINE_EVENT_WITH_TYPED_EVENT_HANDLER(TerminalPage, SetTitleBarContent, _setTitleBarContentHandlers, winrt::Windows::Foundation::IInspectable, UIElement);
-    DEFINE_EVENT_WITH_TYPED_EVENT_HANDLER(TerminalPage, ShowDialog, _showDialogHandlers, winrt::Windows::Foundation::IInspectable, WUX::Controls::ContentDialog);
     DEFINE_EVENT_WITH_TYPED_EVENT_HANDLER(TerminalPage, ToggleFullscreen, _toggleFullscreenHandlers, winrt::Windows::Foundation::IInspectable, winrt::TerminalApp::ToggleFullscreenEventArgs);
 }