fix: preserve transparent TUI diff row tints

.changeset/transparent-tui-diff-tints.md

@@ -0,0 +1,5 @@
+---
+"hunkdiff": patch
+---
+
+Preserve added and removed diff row tints when transparent background mode is enabled in the interactive TUI.

src/ui/App.tsx

@@ -28,7 +28,7 @@ import { fileRowId } from "./lib/ids";
 import { openSelectedFileInEditor } from "./lib/openInEditor";
 import { resolveResponsiveLayout } from "./lib/responsive";
 import { resizeSidebarWidth } from "./lib/sidebar";
-import { availableThemes, resolveTheme, withTransparentBackground } from "./themes";
+import { availableThemes, resolveTheme, withTransparentSurfaces } from "./themes";
 
 type FocusArea = "files" | "filter" | "note";
 type ActiveAddNoteTarget = ActiveAddNoteAffordance & { fileId: string };
@@ -166,7 +166,7 @@ export function App({
   const activeTheme = useMemo(
     () =>
       bootstrap.input.options.transparentBackground
-        ? withTransparentBackground(baseTheme)
+        ? withTransparentSurfaces(baseTheme)
         : baseTheme,
     [baseTheme, bootstrap.input.options.transparentBackground],
   );

src/ui/AppHost.interactions.test.tsx

@@ -2752,6 +2752,40 @@ describe("App interactions", () => {
     }
   });
 
+  test("transparent background keeps added and removed diff row tints", async () => {
+    const bootstrap = createBootstrap();
+    bootstrap.input.options.transparentBackground = true;
+    const theme = resolveTheme(bootstrap.initialTheme, null);
+    const setup = await testRender(<AppHost bootstrap={bootstrap} />, {
+      width: 220,
+      height: 60,
+    });
+
+    try {
+      await flush(setup);
+
+      const frame = setup.captureSpans();
+      const lineIncludesBackground = (text: string, backgroundColor: string) =>
+        frame.lines.some((line) => {
+          const lineText = line.spans.map((span) => span.text).join("");
+          return (
+            lineText.includes(text) &&
+            line.spans.some(
+              (span) =>
+                capturedTestColorToHex(span.bg)?.toLowerCase() === backgroundColor.toLowerCase(),
+            )
+          );
+        });
+
+      expect(lineIncludesBackground("betaValue", theme.addedBg)).toBe(true);
+      expect(lineIncludesBackground("beta = 1", theme.removedBg)).toBe(true);
+    } finally {
+      await act(async () => {
+        setup.renderer.destroy();
+      });
+    }
+  });
+
   test("draft note focus suppresses app shortcuts while accepting typed shortcut keys", async () => {
     const setup = await testRender(<AppHost bootstrap={createBootstrap()} />, {
       width: 240,