feat: unify inline notes and expand behavior coverage

src/core/errors.test.ts

@@ -0,0 +1,36 @@
+import { afterEach, describe, expect, test } from "bun:test";
+import { formatCliError, HunkUserError } from "./errors";
+
+const originalDebug = process.env.HUNK_DEBUG;
+
+afterEach(() => {
+  if (originalDebug === undefined) {
+    delete process.env.HUNK_DEBUG;
+  } else {
+    process.env.HUNK_DEBUG = originalDebug;
+  }
+});
+
+describe("formatCliError", () => {
+  test("formats expected user errors with optional details and no stack", () => {
+    expect(formatCliError(new HunkUserError("Not in a repo"))).toBe("hunk: Not in a repo\n");
+    expect(formatCliError(new HunkUserError("Invalid ref", ["Try `HEAD~1`."]))).toBe(
+      "hunk: Invalid ref\n\nTry `HEAD~1`.\n",
+    );
+  });
+
+  test("hides unexpected stacks unless debug output is explicitly enabled", () => {
+    const error = new Error("Boom");
+    error.stack = "Error: Boom\n    at internal";
+
+    delete process.env.HUNK_DEBUG;
+    expect(formatCliError(error)).toBe("hunk: Boom\n");
+
+    process.env.HUNK_DEBUG = "1";
+    expect(formatCliError(error)).toBe("Error: Boom\n    at internal\n");
+  });
+
+  test("stringifies non-error thrown values", () => {
+    expect(formatCliError("plain failure")).toBe("hunk: plain failure\n");
+  });
+});