babakfp•6mo ago

What does this library "assert" does?

https://deno.land/std@0.215.0/assert/mod.ts What does it do in this example? https://docs.deno.com/runtime/manual/advanced/jsx_dom/deno_dom#basic-example

Using deno-dom with Deno | Deno Docs

deno-dom is an implementation of DOM and HTML

2 Replies

Deno AI Helper•6mo ago

The assert library in Deno is part of the standard library's assertions module, which provides developers with a set of common assertion functions for writing tests. These functions are used to verify that certain conditions are true during the execution of tests. The assert function itself is a simple "truthy" assertion that can be used to assert any value that can be inferred as true. In the context of the example you've provided, the assert function is not directly used. The example from the documentation under the section "Using deno-dom with Deno" does not include the assert function. Instead, it discusses the deno-dom library, which is an implementation of the DOM and HTML parser in Deno. The example likely demonstrates how to use deno-dom to parse HTML and manipulate the resulting DOM structure, but it does not involve the assert function from the assertions module. If you're looking for examples of how the assert function is used, the documentation provides the following example:

import { assert } from "https://deno.land/std@0.215.0/assert/mod.ts";

Deno.test("Test Assert", () => {
  assert(1);
  assert("Hello");
  assert(true);
});

import { assert } from "https://deno.land/std@0.215.0/assert/mod.ts";

Deno.test("Test Assert", () => {
  assert(1);
  assert("Hello");
  assert(true);
});

In this example, the assert function is used within a test case to verify that the provided expressions are truthy. If any of the expressions evaluated to false, the test would fail. 🦕

Helpful Links: Assertions | Deno Docs Documentation Tests | Deno Docs Configuring JSX in Deno | Deno Docs Using jsdom with Deno | Deno Docs

Leokuma•6mo ago

It asserts that document is truthy, which in this case means it's not null If the HTML is invalid, parseFromString() returns null IIRC