Benchmark: Deep equality vs shallow equality

HTML Preparation code:

<script src="https://cdn.jsdelivr.net/npm/lodash@4.17.20/lodash.min.js"></script>

Script Preparation code:

var data = {
    value1: {
        id: 1,
        documentId: 'foo',
        type: 'synonym',
        rephraseType: 'improve',
        selection: {
            start: 0,
            end: 10,
            text: 'bar'
        }
    },
    value2: {
        id: 1,
        documentId: 'foo',
        type: 'synonym',
        rephraseType: 'improve',
        selection: {
            start: 0,
            end: 10,
            text: 'bar'
        }
    }
}

Tests:

lodash
_.isEqual(data.value1, data.value2)
by id
data.value1.id === data.value2.id

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
lodash
by id

Fastest: N/A

Slowest: N/A

Latest run results:

No previous run results

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Autogenerated LLM Summary (model llama3.2:3b, generated one year ago):

LLMs can make mistakes. Check important info.

I'd be happy to help you understand the provided benchmark.

**Benchmark Overview**

The benchmark compares two approaches for equality checks in JavaScript: deep equality and shallow equality. The test case uses Lodash, a popular utility library, to perform the equality checks.

**Test Case 1: "by id"**

This test case performs an equality check using the `===` operator on the `id` property of two objects, `data.value1` and `data.value2`. This approach is known as "shallow equality" or "value-based comparison". It simply checks if the values of the `id` properties are equal.

Pros:

* Simple and efficient
* Fast execution

Cons:

* May not work correctly for complex data structures, like nested objects or arrays
* Does not account for object references

**Test Case 2: "lodash"**

This test case uses Lodash's `_isEqual()` function to perform a deep equality check on the `data.value1` and `data.value2` objects. This approach checks if both objects have the same properties, values, and structure.

Pros:

* Works correctly for complex data structures
* Accounts for object references

Cons:

* May be slower than shallow equality due to the additional work done by Lodash
* Requires an extra library dependency (Lodash)

**Other Considerations**

* The benchmark also compares the execution speed of the two approaches. This is because deep equality checks can be more computationally expensive, especially for large data structures.
* Using a library like Lodash can add overhead to the test case, which may affect its performance.

**Library: Lodash**

Lodash is a popular JavaScript utility library that provides a wide range of functions for tasks such as array manipulation, object iteration, and equality checks. In this benchmark, Lodash's `_isEqual()` function is used to perform the deep equality check.

**Special JS Feature/Syntax: None**

There are no special features or syntaxes mentioned in the provided code snippet.

**Alternatives**

If you want to implement your own shallow equality check, you can use a simple implementation like this:
```javascript
function shallowEqual(a, b) {
  return JSON.stringify(a) === JSON.stringify(b);
}
```
Alternatively, if you prefer to avoid using Lodash or other libraries, you can implement a custom deep equality check using recursion or iterative methods. However, these implementations may be more complex and error-prone.

Overall, the benchmark provides a useful comparison of two common approaches for equality checks in JavaScript: shallow equality and deep equality with the help of a library like Lodash.

Related benchmarks:

Deep equality vs shallow equality (version: 0)

Comparing performance of: lodash vs by id

Created: 3 years ago by: Guest

Jump to the latest result

lodash

by id

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

No previous run results

Autogenerated LLM Summary (model llama3.2:3b, generated one year ago):