test_inspect_custom.cjs
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test_inspect_custom.cjs
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	const { inspect } = require('node:util');

	function assert(cond, msg) {
	if (!cond) throw new Error(msg);
	}

	assert(typeof Symbol.inspect === 'symbol', 'expected Symbol.inspect to exist');
	assert(Symbol.inspect !== Symbol.for('ant.inspect'), 'expected Symbol.inspect to stay separate from the global registry');
	assert(Symbol.keyFor(Symbol.inspect) === undefined, 'expected Symbol.inspect to not be registry-backed');

	class Connection {
	constructor(host, port, state) {
	this.host = host;
	this.port = port;
	this.state = state;
	}

	[Symbol.inspect]() {
	return `Connection { ${this.host}:${this.port} (${this.state}) }`;
	}
	}

	class FallbackConnection {
	constructor(host) {
	this.host = host;
	}

	[Symbol.inspect]() {
	throw new Error('boom');
	}
	}

	const blob = new Blob(['hi'], { type: 'text/plain' });
	const file = new File(['hi'], 'note.txt', { type: 'text/plain', lastModified: 42 });
	const headers = new Headers({ 'content-type': 'text/plain' });
	const request = new Request('https://google.com');
	const response = new Response('ok', { headers });
	const timeout = setTimeout(() => {}, 1);
	const interval = setInterval(() => {}, 5);
	const headersInspect = inspect(headers);
	const timeoutInspect = inspect(timeout);
	const intervalInspect = inspect(interval);
	const requestInspect = inspect(request);
	const responseInspect = inspect(response);

	assert(typeof Headers.prototype[Symbol.inspect] === 'function', 'expected Headers.prototype[Symbol.inspect] to exist');
	assert(typeof Request.prototype[Symbol.inspect] === 'function', 'expected Request.prototype[Symbol.inspect] to exist');
	assert(typeof Response.prototype[Symbol.inspect] === 'function', 'expected Response.prototype[Symbol.inspect] to exist');

	assert(inspect(new Connection('localhost', 3000, 'open')) === 'Connection { localhost:3000 (open) }', 'expected custom inspect result');
	assert(inspect(blob) === "Blob { size: 2, type: 'text/plain' }", 'expected Blob custom inspect output');
	assert(inspect(file) === "File { size: 2, type: 'text/plain', name: 'note.txt', lastModified: 42 }", 'expected File custom inspect output');
	assert(
	Headers.prototype[Symbol.inspect].call(headers) === headersInspect,
	`expected Headers Symbol.inspect output, got: ${Headers.prototype[Symbol.inspect].call(headers)}`
	);
	assert(
	requestInspect === "Request {\n method: 'GET',\n url: 'https://google.com/',\n headers: Headers {},\n destination: '',\n referrer: 'about:client',\n referrerPolicy: '',\n mode: 'cors',\n credentials: 'same-origin',\n cache: 'default',\n redirect: 'follow',\n integrity: '',\n keepalive: false,\n isReloadNavigation: false,\n isHistoryNavigation: false,\n signal: AbortSignal { aborted: false }\n}",
	`expected Request inspect output, got: ${requestInspect}`
	);
	assert(
	Request.prototype[Symbol.inspect].call(request) === requestInspect,
	`expected Request Symbol.inspect output, got: ${Request.prototype[Symbol.inspect].call(request)}`
	);
	assert(
	Response.prototype[Symbol.inspect].call(response) === responseInspect,
	`expected Response Symbol.inspect output, got: ${Response.prototype[Symbol.inspect].call(response)}`
	);
	assert(
	timeoutInspect === 'Timeout (1) {\n delay: 1,\n repeat: null,\n [Symbol(Symbol.toPrimitive)]: [native code]\n}',
	`expected legacy Timeout inspect output, got: ${timeoutInspect}`
	);
	assert(
	intervalInspect === 'Interval (2) {\n delay: 5,\n repeat: 5,\n [Symbol(Symbol.toPrimitive)]: [native code]\n}',
	`expected legacy Interval inspect output, got: ${intervalInspect}`
	);

	clearTimeout(timeout);
	clearInterval(interval);

	const fallback = inspect(new FallbackConnection('db.internal'));
	assert(
	fallback === "FallbackConnection { host: 'db.internal' }",
	`expected fallback formatting after inspect throw, got: ${fallback}`
	);

	console.log('PASS');

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