From f96967ab722fe74eafed6dfdf6f3cbcbc5a4a0fc Mon Sep 17 00:00:00 2001
From: Nate Moore <git@natemoo.re>
Date: Thu, 4 Jun 2026 00:51:35 -0500
Subject: [PATCH] test: failing repro for color-encoding-modes

---
 test/color-encoding-modes.test.ts | 41 +++++++++++++++++++++++++++++++
 1 file changed, 41 insertions(+)
 create mode 100644 test/color-encoding-modes.test.ts

diff --git a/test/color-encoding-modes.test.ts b/test/color-encoding-modes.test.ts
new file mode 100644
index 0000000..081a15f
--- /dev/null
+++ b/test/color-encoding-modes.test.ts
@@ -0,0 +1,41 @@
+import { describe, expect, it } from "./suite.ts";
+import { createTerm } from "../term.ts";
+import { close, grow, open, rgba, text } from "../ops.ts";
+
+const decode = (b: Uint8Array) => new TextDecoder().decode(b);
+
+describe("color encoding modes", () => {
+  it("16-color mode downgrades standard red foreground to 4-bit", async () => {
+    let term = await createTerm({ width: 4, height: 1 });
+    let ansi = decode(
+      term.render([
+        open("root", { layout: { width: grow(), height: grow() } }),
+        text("X", { color: rgba(255, 0, 0) }),
+        close(),
+        // deno-lint-ignore no-explicit-any
+      ], { colorMode: "16" } as any).output,
+    );
+
+    let before = ansi.slice(0, ansi.indexOf("X"));
+    // pins: standard-palette red maps to 4-bit \x1b[31m under colorMode:"16"
+    expect(before).toContain("\x1b[31m");
+    // pins: the 24-bit sequence must not survive the downgrade
+    expect(before).not.toContain("\x1b[38;2;255;0;0");
+  });
+
+  it("256-color mode downgrades standard red foreground to a palette index", async () => {
+    let term = await createTerm({ width: 4, height: 1 });
+    let ansi = decode(
+      term.render([
+        open("root", { layout: { width: grow(), height: grow() } }),
+        text("X", { color: rgba(255, 0, 0) }),
+        close(),
+        // deno-lint-ignore no-explicit-any
+      ], { colorMode: "256" } as any).output,
+    );
+
+    let before = ansi.slice(0, ansi.indexOf("X"));
+    // pins: standard-palette red maps to index 1 (\x1b[38;5;1m) under colorMode:"256"
+    expect(before).toContain("\x1b[38;5;1m");
+  });
+});
-- 
2.51.2