From ce0c42f539a355fdcde770ef81299505d21af79d Mon Sep 17 00:00:00 2001
From: Mario Rodler <m.rodler@m-box.at>
Date: Sun, 16 Nov 2025 18:15:21 +0100
Subject: [PATCH] test(editor): Add tests for handling extended characters,
 emojis, and special key inputs

---
 packages/tui/src/components/editor.ts |   2 +-
 packages/tui/test/editor.test.ts      | 171 ++++++++++++++++++++++++++
 2 files changed, 172 insertions(+), 1 deletion(-)
 create mode 100644 packages/tui/test/editor.test.ts

diff --git a/packages/tui/src/components/editor.ts b/packages/tui/src/components/editor.ts
index 99b04b6e..67ea7e52 100644
--- a/packages/tui/src/components/editor.ts
+++ b/packages/tui/src/components/editor.ts
@@ -472,7 +472,7 @@ export class Editor implements Component {
 		// Filter out non-printable characters except newlines
 		const filteredText = tabExpandedText
 			.split("")
-			.filter((char) => char === "\n" || (char >= " " && char <= "~"))
+			.filter((char) => char === "\n" || char.length > 0)
 			.join("");
 
 		// Split into lines
diff --git a/packages/tui/test/editor.test.ts b/packages/tui/test/editor.test.ts
new file mode 100644
index 00000000..971fbecc
--- /dev/null
+++ b/packages/tui/test/editor.test.ts
@@ -0,0 +1,171 @@
+import assert from "node:assert";
+import { describe, it } from "node:test";
+import { Editor } from "../src/components/editor.js";
+
+describe("Editor component", () => {
+	describe("Unicode character input", () => {
+		it("should handle German umlauts correctly", () => {
+			const editor = new Editor();
+
+			// Simulate typing umlauts
+			editor.handleInput("ä");
+			editor.handleInput("ö");
+			editor.handleInput("ü");
+			editor.handleInput("Ä");
+			editor.handleInput("Ö");
+			editor.handleInput("Ü");
+			editor.handleInput("ß");
+
+			const text = editor.getText();
+			assert.strictEqual(text, "äöüÄÖÜß");
+		});
+
+		it("should handle emojis correctly", () => {
+			const editor = new Editor();
+
+			// Simulate typing emojis
+			editor.handleInput("😀");
+			editor.handleInput("👍");
+			editor.handleInput("🎉");
+
+			const text = editor.getText();
+			assert.strictEqual(text, "😀👍🎉");
+		});
+
+		it("should handle mixed ASCII, umlauts, and emojis", () => {
+			const editor = new Editor();
+
+			editor.handleInput("H");
+			editor.handleInput("e");
+			editor.handleInput("l");
+			editor.handleInput("l");
+			editor.handleInput("o");
+			editor.handleInput(" ");
+			editor.handleInput("ä");
+			editor.handleInput("ö");
+			editor.handleInput("ü");
+			editor.handleInput(" ");
+			editor.handleInput("😀");
+
+			const text = editor.getText();
+			assert.strictEqual(text, "Hello äöü 😀");
+		});
+
+		it("should handle backspace with umlauts correctly", () => {
+			const editor = new Editor();
+
+			editor.handleInput("ä");
+			editor.handleInput("ö");
+			editor.handleInput("ü");
+
+			// Delete the last character (ü)
+			editor.handleInput("\x7f"); // Backspace
+
+			const text = editor.getText();
+			assert.strictEqual(text, "äö");
+		});
+
+		it("should handle backspace with emojis correctly", () => {
+			const editor = new Editor();
+
+			editor.handleInput("😀");
+			editor.handleInput("👍");
+
+			// Delete the last emoji (👍) - requires 2 backspaces since emojis are 2 code units
+			editor.handleInput("\x7f"); // Backspace
+			editor.handleInput("\x7f"); // Backspace
+
+			const text = editor.getText();
+			assert.strictEqual(text, "😀");
+		});
+
+		it("should handle cursor movement with umlauts", () => {
+			const editor = new Editor();
+
+			editor.handleInput("ä");
+			editor.handleInput("ö");
+			editor.handleInput("ü");
+
+			// Move cursor left twice
+			editor.handleInput("\x1b[D"); // Left arrow
+			editor.handleInput("\x1b[D"); // Left arrow
+
+			// Insert 'x' in the middle
+			editor.handleInput("x");
+
+			const text = editor.getText();
+			assert.strictEqual(text, "äxöü");
+		});
+
+		it("should handle cursor movement with emojis", () => {
+			const editor = new Editor();
+
+			editor.handleInput("😀");
+			editor.handleInput("👍");
+			editor.handleInput("🎉");
+
+			// Move cursor left twice (should skip the emoji)
+			editor.handleInput("\x1b[D"); // Left arrow
+			editor.handleInput("\x1b[D"); // Left arrow
+
+			// Note: Emojis are 2 code units, so we need to move left twice per emoji
+			// But cursor position is in code units, not visual columns
+			editor.handleInput("\x1b[D");
+			editor.handleInput("\x1b[D");
+
+			// Insert 'x'
+			editor.handleInput("x");
+
+			const text = editor.getText();
+			assert.strictEqual(text, "😀x👍🎉");
+		});
+
+		it("should handle multi-line text with umlauts", () => {
+			const editor = new Editor();
+
+			editor.handleInput("ä");
+			editor.handleInput("ö");
+			editor.handleInput("ü");
+			editor.handleInput("\n"); // Shift+Enter (new line)
+			editor.handleInput("Ä");
+			editor.handleInput("Ö");
+			editor.handleInput("Ü");
+
+			const text = editor.getText();
+			assert.strictEqual(text, "äöü\nÄÖÜ");
+		});
+
+		it("should handle paste with umlauts", () => {
+			const editor = new Editor();
+
+			// Simulate bracketed paste by calling handlePaste directly
+			// (Bracketed paste is async and doesn't work well in sync tests)
+			editor.setText("äöüÄÖÜß");
+
+			const text = editor.getText();
+			assert.strictEqual(text, "äöüÄÖÜß");
+		});
+
+		it("should handle special control keys", () => {
+			const editor = new Editor();
+
+			// Ctrl+A moves cursor to start
+			editor.handleInput("a");
+			editor.handleInput("b");
+			editor.handleInput("\x01"); // Ctrl+A (move to start)
+			editor.handleInput("x"); // Insert at start
+
+			const text = editor.getText();
+			assert.strictEqual(text, "xab");
+		});
+
+		it("should handle setText with umlauts", () => {
+			const editor = new Editor();
+
+			editor.setText("Hällö Wörld! 😀");
+
+			const text = editor.getText();
+			assert.strictEqual(text, "Hällö Wörld! 😀");
+		});
+	});
+});