Only update the icon of a tab it the icon actually _changed_

src/cascadia/TerminalApp/App.cpp

@@ -7,6 +7,7 @@
 
 #include "App.g.cpp"
 #include "TerminalPage.h"
+#include "Utils.h"
 
 using namespace winrt::Windows::ApplicationModel::DataTransfer;
 using namespace winrt::Windows::UI::Xaml;
@@ -686,16 +687,15 @@ namespace winrt::TerminalApp::implementation
         if (lastFocusedProfileOpt.has_value())
         {
             const auto lastFocusedProfile = lastFocusedProfileOpt.value();
-
-            auto tabViewItem = tab->GetTabViewItem();
-            tabViewItem.Dispatcher().RunAsync(CoreDispatcherPriority::Normal, [this, lastFocusedProfile, tabViewItem]() {
-                // _GetIconFromProfile has to run on the main thread
-                const auto* const matchingProfile = _settings->FindProfile(lastFocusedProfile);
-                if (matchingProfile)
-                {
-                    tabViewItem.Icon(App::_GetIconFromProfile(*matchingProfile));
-                }
-            });
+            const auto* const matchingProfile = _settings->FindProfile(lastFocusedProfile);
+            if (matchingProfile)
+            {
+                tab->UpdateIcon(matchingProfile->GetExpandedIconPath());
+            }
+            else
+            {
+                tab->UpdateIcon({});
+            }
         }
     }
 
@@ -928,7 +928,7 @@ namespace winrt::TerminalApp::implementation
         // Set this profile's tab to the icon the user specified
         if (profile != nullptr && profile->HasIcon())
         {
-            tabViewItem.Icon(_GetIconFromProfile(*profile));
+            newTab->UpdateIcon(profile->GetExpandedIconPath());
         }
 
         tabViewItem.PointerPressed({ this, &App::_OnTabClick });
@@ -1252,19 +1252,13 @@ namespace winrt::TerminalApp::implementation
     {
         if (profile.HasIcon())
         {
-            std::wstring path{ profile.GetIconPath() };
-            const auto envExpandedPath{ wil::ExpandEnvironmentStringsW<std::wstring>(path.data()) };
-            winrt::hstring iconPath{ envExpandedPath };
-            winrt::Windows::Foundation::Uri iconUri{ iconPath };
-            Controls::BitmapIconSource iconSource;
-            // Make sure to set this to false, so we keep the RGB data of the
-            // image. Otherwise, the icon will be white for all the
-            // non-transparent pixels in the image.
-            iconSource.ShowAsMonochrome(false);
-            iconSource.UriSource(iconUri);
-            Controls::IconSourceElement elem;
-            elem.IconSource(iconSource);
-            return elem;
+            try
+            {
+                winrt::hstring iconPath{ profile.GetExpandedIconPath() };
+                return GetColoredIcon(iconPath);
+            }
+            CATCH_LOG();
+            return { nullptr };
         }
         else
         {

src/cascadia/TerminalApp/Profile.cpp

@@ -568,14 +568,19 @@ void Profile::SetIconPath(std::wstring_view path)
 }
 
 // Method Description:
-// - Returns this profile's icon path, if one is set. Otherwise returns the empty string.
+// - Returns this profile's icon path, if one is set. Otherwise returns the
+//   empty string. This method will expand any environment variables in the
+//   path, if there are any.
 // Return Value:
 // - this profile's icon path, if one is set. Otherwise returns the empty string.
-std::wstring_view Profile::GetIconPath() const noexcept
+winrt::hstring Profile::GetExpandedIconPath() const
 {
-    return HasIcon() ?
-               std::wstring_view{ _icon.value().c_str(), _icon.value().size() } :
-               std::wstring_view{ L"", 0 };
+    if (!HasIcon())
+    {
+        return { L"" };
+    }
+    winrt::hstring envExpandedPath{ wil::ExpandEnvironmentStringsW<std::wstring>(_icon.value().data()) };
+    return envExpandedPath;
 }
 
 // Method Description:

src/cascadia/TerminalApp/Profile.h

@@ -55,7 +55,7 @@ class TerminalApp::Profile final
     void SetConnectionType(GUID connectionType) noexcept;
 
     bool HasIcon() const noexcept;
-    std::wstring_view GetIconPath() const noexcept;
+    winrt::hstring GetExpandedIconPath() const;
     void SetIconPath(std::wstring_view path);
 
     bool GetCloseOnExit() const noexcept;

src/cascadia/TerminalApp/Tab.cpp

@@ -3,6 +3,7 @@
 
 #include "pch.h"
 #include "Tab.h"
+#include "Utils.h"
 
 using namespace winrt::Windows::UI::Xaml;
 using namespace winrt::Windows::UI::Core;
@@ -142,6 +143,21 @@ void Tab::UpdateFocus()
     _rootPane->UpdateFocus();
 }
 
+void Tab::UpdateIcon(const winrt::hstring iconPath)
+{
+    // Don't reload our icon if it hasn't changed.
+    if (iconPath == _lastIconPath)
+    {
+        return;
+    }
+
+    _lastIconPath = iconPath;
+
+    _tabViewItem.Dispatcher().RunAsync(CoreDispatcherPriority::Normal, [this]() {
+        _tabViewItem.Icon(GetColoredIcon(_lastIconPath));
+    });
+}
+
 // Method Description:
 // - Gets the title string of the last focused terminal control in our tree.
 //   Returns the empty string if there is no such control.

src/cascadia/TerminalApp/Tab.h

@@ -23,6 +23,8 @@ class Tab
     void AddHorizontalSplit(const GUID& profile, winrt::Microsoft::Terminal::TerminalControl::TermControl& control);
 
     void UpdateFocus();
+    void UpdateIcon(const winrt::hstring iconPath);
+
     void ResizeContent(const winrt::Windows::Foundation::Size& newSize);
     void ResizePane(const winrt::TerminalApp::Direction& direction);
     void NavigateFocus(const winrt::TerminalApp::Direction& direction);
@@ -37,6 +39,7 @@ class Tab
 
 private:
     std::shared_ptr<Pane> _rootPane{ nullptr };
+    winrt::hstring _lastIconPath{};
 
     bool _focused{ false };
     winrt::Microsoft::UI::Xaml::Controls::TabViewItem _tabViewItem{ nullptr };

src/cascadia/TerminalApp/Utils.cpp

@@ -16,3 +16,30 @@ std::wstring GetWstringFromJson(const Json::Value& json)
 {
     return winrt::to_hstring(json.asString()).c_str();
 }
+
+// Method Description:
+// - Creates an IconElement for the given path. The icon returned is a colored
+//   icon. If we couldn't create the icon for any reason, we return an empty
+//   IconElement.
+// Arguments:
+// - path: the full, expanded path to the icon.
+// Return Value:
+// - An IconElement with its IconSource set, if possible.
+winrt::Windows::UI::Xaml::Controls::IconElement GetColoredIcon(const winrt::hstring& path)
+{
+    winrt::Windows::UI::Xaml::Controls::IconSourceElement elem{};
+    try
+    {
+        winrt::Windows::Foundation::Uri iconUri{ path };
+        winrt::Windows::UI::Xaml::Controls::BitmapIconSource iconSource;
+        // Make sure to set this to false, so we keep the RGB data of the
+        // image. Otherwise, the icon will be white for all the
+        // non-transparent pixels in the image.
+        iconSource.ShowAsMonochrome(false);
+        iconSource.UriSource(iconUri);
+        elem.IconSource(iconSource);
+    }
+    CATCH_LOG();
+
+    return elem;
+}

src/cascadia/TerminalApp/Utils.h

@@ -28,3 +28,5 @@ inline std::string JsonKey(const std::string_view key)
 {
     return static_cast<std::string>(key);
 }
+
+winrt::Windows::UI::Xaml::Controls::IconElement GetColoredIcon(const winrt::hstring& path);