From c54f646e52062e1fcf5e9cd85fee1271c7adc902 Mon Sep 17 00:00:00 2001
From: "google-labs-jules[bot]"
 <161369871+google-labs-jules[bot]@users.noreply.github.com>
Date: Thu, 11 Jun 2026 03:34:17 +0000
Subject: [PATCH] test: add tests for truncate utility in format.ts

Implemented tests for the `truncate` string utility function covering happy paths (strings shorter, exactly matching, and longer than the limit) and edge cases including empty strings, limits of 0 or 1, and negative limit boundaries. These changes increase test coverage without altering any core logic.

Co-authored-by: toreleon <42534763+toreleon@users.noreply.github.com>
---
 tests/format.test.ts | 34 ++++++++++++++++++++++++++++++++++
 1 file changed, 34 insertions(+)
 create mode 100644 tests/format.test.ts

diff --git a/tests/format.test.ts b/tests/format.test.ts
new file mode 100644
index 0000000..97e1e1c
--- /dev/null
+++ b/tests/format.test.ts
@@ -0,0 +1,34 @@
+import { describe, expect, it } from "vitest";
+import { truncate } from "../src/tui/lib/format.js";
+
+describe("truncate", () => {
+  it("returns the original string if it is shorter than the limit", () => {
+    expect(truncate("hello", 10)).toBe("hello");
+  });
+
+  it("returns the original string if its length is exactly the limit", () => {
+    expect(truncate("hello", 5)).toBe("hello");
+  });
+
+  it("truncates and appends an ellipsis if the string is longer than the limit", () => {
+    expect(truncate("hello world", 5)).toBe("hell…");
+    expect(truncate("hello world", 8)).toBe("hello w…");
+  });
+
+  it("handles empty strings correctly", () => {
+    expect(truncate("", 5)).toBe("");
+    expect(truncate("", 0)).toBe("");
+  });
+
+  it("handles limit of 0 correctly", () => {
+    expect(truncate("hello", 0)).toBe("…");
+  });
+
+  it("handles limit of 1 correctly", () => {
+    expect(truncate("hello", 1)).toBe("…");
+  });
+
+  it("handles negative limits correctly", () => {
+    expect(truncate("hello", -5)).toBe("…");
+  });
+});