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web_deno_test: Run your tests on Deno and web browsers at a time

This script enables your test suite to run on Deno and web browsers at a time.

How to write tests

You need to use the suite() function from mod.ts:

import { assertEquals } from "https://deno.land/std@0.92.0/testing/asserts.ts";
import suite from "https://deno.land/x/web_deno_test/mod.ts";

const test = suite(import.meta.url);

test("1 plus 2 equals 3", () => {
  assertEquals(1 + 2, 3);
});

How to run tests on Deno

The standard Deno test command works:

$ deno test
Check file:///.../$deno$test.ts
running 1 tests
test 1 plus 2 equals 3 ... ok (3ms)

test result: ok. 1 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out (3ms)

How to run tests on web browsers

The cli.ts script scans test files and turns them into Mocha-based tests:

$ deno run \
    --unstable \
    --allow-read=. \
    --allow-write=tests/ \
    --allow-net \
    https://deno.land/x/web_deno_test/cli.ts \
    --output-dir tests/ \
    .
Check .../cli.ts

Note that the script requires --unstable API as of Deno 1.9.

The built index.html should be opened through http:/https: (not file:) on web browser due to security policies:

$ deno run \
    --allow-net \
    --allow-read=. \
    https://deno.land/std/http/file_server.ts \
    tests/

Then, open http://0.0.0.0:4507/ on your web browser. It will run your tests:

Tests ran on web browser.