deno/cli/js/tests

Deno runtime tests

Files in this directory are unit tests for Deno runtime.

They are run under compiled Deno binary as opposed to files in cli/js/ which are bundled and snapshotted using deno_typescript crate.

Testing Deno runtime code requires checking API under different runtime permissions (ie. running with different --allow-* flags). To accomplish this all tests exercised are created using unitTest() function.

import { unitTest } from "./test_util.ts";

unitTest(function simpleTestFn(): void {
  // test code here
});

unitTest({
    skip: Deno.build.os === "win",
    perms: { read: true, write: true },
  },
  function complexTestFn(): void {
    // test code here
  }
);

unitTest is is a wrapper function that enhances Deno.test() API in several ways:

• ability to conditionally skip tests using UnitTestOptions.skip
• ability to register required set of permissions for given test case using UnitTestOptions.perms
• sanitization of resources - ensuring that tests close all opened resources preventing interference between tests
• sanitization of async ops - ensuring that tests don't leak async ops by ensuring that all started async ops are done before test finishes

Running tests

unit_test_runner.ts is the main script used to run unit tests.

Runner discoveres required permissions combinations by loading cli/js/tests/unit_tests.ts and going through all registered instances of unitTest.

There are three ways to run unit_test_runner.ts:

• run tests matching current process permissions

// run tests that don't require any permissions
target/debug/deno unit_test_runner.ts

// run tests with "net" permission
target/debug/deno --allow-net unit_test_runner.ts

target/debug/deno --allow-net --allow-read unit_test_runner.ts

• run all tests - "master" mode, that spawns worker processes for each discovered permission combination:

target/debug/deno -A unit_test_runner.ts --master

By default all output of worker processes is discarded; for debug purposes --verbose flag can be provided to preserve output from worker

target/debug/deno -A unit_test_runner.ts --master --verbose

• "worker" mode; communicates with parent using TCP socket on provided address; after initial setup drops permissions to specified set. It shouldn't be used directly, only be "master" process.

target/debug/deno -A unit_test_runner.ts --worker --addr=127.0.0.1:4500 --perms=net,write,run

Filtering

Runner supports basic test filtering by name:

target/debug/deno unit_test_runner.ts -- netAccept

target/debug/deno -A unit_test_runner.ts --master -- netAccept

Filter string must be specified after "--" argument