1 files changed, 66 insertions, 0 deletions
diff --git a/tests/unit_node/assertion_error_test.ts b/tests/unit_node/assertion_error_test.ts
new file mode 100644
index 000000000..b61baee93
--- /dev/null
+++ b/tests/unit_node/assertion_error_test.ts
@@ -0,0 +1,66 @@
+// Copyright 2018-2024 the Deno authors. All rights reserved. MIT license.
+import { stripColor } from "@test_util/std/fmt/colors.ts";
+import { assert, assertStrictEquals } from "@test_util/std/assert/mod.ts";
+import { AssertionError } from "node:assert";
+
+Deno.test({
+  name: "construct AssertionError() with given message",
+  fn() {
+    const err = new AssertionError(
+      {
+        message: "answer",
+        actual: "42",
+        expected: "42",
+        operator: "notStrictEqual",
+      },
+    );
+    assertStrictEquals(err.name, "AssertionError");
+    assertStrictEquals(err.message, "answer");
+    assertStrictEquals(err.generatedMessage, false);
+    assertStrictEquals(err.code, "ERR_ASSERTION");
+    assertStrictEquals(err.actual, "42");
+    assertStrictEquals(err.expected, "42");
+    assertStrictEquals(err.operator, "notStrictEqual");
+  },
+});
+
+Deno.test({
+  name: "construct AssertionError() with generated message",
+  fn() {
+    const err = new AssertionError(
+      { actual: 1, expected: 2, operator: "equal" },
+    );
+    assertStrictEquals(err.name, "AssertionError");
+    assertStrictEquals(stripColor(err.message), "1 equal 2");
+    assertStrictEquals(err.generatedMessage, true);
+    assertStrictEquals(err.code, "ERR_ASSERTION");
+    assertStrictEquals(err.actual, 1);
+    assertStrictEquals(err.expected, 2);
+    assertStrictEquals(err.operator, "equal");
+  },
+});
+
+Deno.test({
+  name: "construct AssertionError() with stackStartFn",
+  fn: function stackStartFn() {
+    const expected = /node/;
+    const err = new AssertionError({
+      actual: "deno",
+      expected,
+      operator: "match",
+      stackStartFn,
+    });
+    assertStrictEquals(err.name, "AssertionError");
+    assertStrictEquals(stripColor(err.message), `'deno' match /node/`);
+    assertStrictEquals(err.generatedMessage, true);
+    assertStrictEquals(err.code, "ERR_ASSERTION");
+    assertStrictEquals(err.actual, "deno");
+    assertStrictEquals(err.expected, expected);
+    assertStrictEquals(err.operator, "match");
+    assert(err.stack, "error should have a stack");
+    assert(
+      !err.stack?.includes("stackStartFn"),
+      "stackStartFn() should not present in stack trace",
+    );
+  },
+});