Why Does `console.log` Sometimes Show the Wrong Object State, and How Can I Fix It?

How to Display the Current State of an Object in Console.log

When using console.log to output an object, you may encounter an issue where the displayed object reflects its state at the time of the final execution, not when console.log was initially invoked. This discrepancy can be particularly evident in Safari and browsers without additional extensions.

Issue:

Consider the following example:

var test = { a: true };
console.log(test); // {a: false}
test.a = false; 
console.log(test); // {a: false}

In this scenario, the second console.log call incorrectly displays {a: false}, even though the actual value of the 'a' property has been assigned to 'false'.

Solution: Using console.dir()

To resolve this issue and display the current state of the object when console.log is called, you can leverage the console.dir() function. Unlike console.log(), console.dir() provides a directory of the object's properties at the time of invocation, providing an accurate representation of the object's state.

Using JSON Stringification:

Alternatively, you can utilize JSON stringification and parsing to achieve a similar result:

console.log(JSON.parse(JSON.stringify(obj)));

This approach involves converting the object to a JSON string using JSON.stringify() and then parsing it back to a JSON object using JSON.parse(). This effectively clones the object, allowing you to display its current state accurately.

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