util: throw toJSON errors when formatting %j

util: throw toJSON errors when formatting %j · nodejs/node@455e6f1

Original file line number	Diff line number	Diff line change
`@@ -86,6 +86,16 @@ assert.strictEqual(util.format('o: %j, a: %j'), 'o: %j, a: %j');`
`86`	`86`	`assert.strictEqual(util.format('%j', o), '[Circular]');`
`87`	`87`	`}`
`88`	`88`
	`89`	`+{`
	`90`	`+const o = {`
	`91`	`+toJSON() {`
	`92`	`+throw new Error('Not a circular object but still not serializable');`
	`93`	`+}`
	`94`	`+};`
	`95`	`+assert.throws(() => util.format('%j', o),`
	`96`	`+/^Error: Not a circular object but still not serializable$/);`
	`97`	`+}`
	`98`	`+`
`89`	`99`	`// Errors`
`90`	`100`	`const err = new Error('foo');`
`91`	`101`	`assert.strictEqual(util.format(err), err.stack);`