Support compat mode in deno test

[Soremwar]

As indicated by the title

This would be useful to run other test runners assertions under deno test and easing the migration of node codebases into Deno

Would be specially useful for deno_std, where the Node native tests are run as a subprocess instead of being run directly under compat mode (this is really annoying for local debugging, specially with average CPUs)

[bartlomieju]

The first step is to update set up code for worker in cli/tools/test.rs:

deno/cli/tools/test.rs

Lines 455 to 460 in 42777f2

	let mut worker = create_main_worker(
	&ps,
	specifier.clone(),
	permissions,
	vec![ops::testing::init(channel.clone())],
	);

The setup will be mostly the same like in cli/main.rs:

deno/cli/main.rs

Lines 1154 to 1182 in 42777f2

	if flags.compat {
	// TODO(bartlomieju): fix me
	assert_eq!(main_module.scheme(), "file");
	// Set up Node globals
	worker.execute_side_module(&compat::GLOBAL_URL).await?;
	// And `module` module that we'll use for checking which
	// loader to use and potentially load CJS module with.
	// This allows to skip permission check for `--allow-net`
	// which would otherwise be requested by dynamically importing
	// this file.
	worker.execute_side_module(&compat::MODULE_URL).await?;
	let use_esm_loader = compat::check_if_should_use_esm_loader(&main_module)?;
	if use_esm_loader {
	// ES module execution in Node compatiblity mode
	worker.execute_main_module(&main_module).await?;
	} else {
	// CJS module execution in Node compatiblity mode
	compat::load_cjs_module(
	&mut worker.js_runtime,
	&main_module.to_file_path().unwrap().display().to_string(),
	)?;
	}
	} else {
	// Regular ES module execution
	worker.execute_main_module(&main_module).await?;
	}

Specifically this bit needs to be updated:

deno/cli/tools/test.rs

Lines 477 to 481 in 42777f2

	// We only execute the specifier as a module if it is tagged with TestMode::Module or
	// TestMode::Both.
	if mode != TestMode::Documentation {
	// We execute the module module as a side module so that import.meta.main is not set.
	worker.execute_side_module(&specifier).await?;

I expect that we will need to tweak some type checking settings, as running multiple test files will cause to type check of deno_std/node multiple times, but it's a something that can be addressed in follow up PRs.