Benchmark: Object.assign vs {...newValue} 2

Tests:

With Object.assign
const row = {id: 1, label: 'asdf'}; const newRow = Object.assign({}, row, { label: `${row.label} !!!` })
With {...newValue}
const row = {id: 1, label: 'asdf'}; const newRow = {...row, label: `${row.label} !!!` }

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Suite status: <idle, ready to run>

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Test case name	Result
With Object.assign
With {...newValue}

Fastest: N/A

Slowest: N/A

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Autogenerated LLM Summary (model gemma2:9b, generated one year ago):

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This benchmark on MeasureThat.net compares two ways of creating a new object based on an existing one in JavaScript:

**1. `Object.assign({}, row, { label: `${row.label} !!!` })`:** This approach uses the `Object.assign()` method to create a new object by merging properties from three sources:
   - An empty object (`{}`) that acts as the initial target for the merged properties.
   - The existing `row` object, whose properties will be copied.
   - A new object `{ label: `${row.label} !!!` }`, which adds a modified `label` property to the new object.

**2.  `{...row, label: `${row.label} !!!`}`:** This approach uses the spread syntax (`...`), introduced in ES6 (ECMAScript 2015). It creates a new object by spreading the properties of the existing `row` object and adding a modified `label` property directly.

**Pros and Cons:**

* **`Object.assign()`:**
    * **Pros:**  More versatile, as it can merge objects beyond simple key-value pairs. 
    * **Cons:** Can be more verbose than the spread syntax. May perform slightly worse in some scenarios due to extra method calls.

* **Spread Syntax (`{...row,...}`):**
    * **Pros:**  Concise and readable, especially for simpler object merges. Often performs better than `Object.assign()` in benchmarks.
    * **Cons:** Less flexible for more complex merging scenarios.

**Considerations:**

* **Readability:** The spread syntax (`{...}`) is generally considered more concise and readable. 
* **Performance:** In this specific benchmark, the spread syntax outperformed `Object.assign()`. However, performance can vary depending on the complexity of the objects being merged and other factors.

**Alternatives:**

While not directly compared in this benchmark, other alternatives for object manipulation include:

* **Object Literal Notation:** Manually creating new objects by listing key-value pairs (e.g., `{ id: 1, label: 'asdf' }`).
* **Lodash/Underscore Libraries:** These libraries provide functions like `_.assign()` and `_.merge()` that offer more advanced object merging capabilities.

Let me know if you have any other questions!

Related benchmarks:

Object.assign vs {...newValue} 2 (version: 1)

Comparing performance of: With Object.assign vs With {...newValue}

Created: 5 years ago by: Registered User

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With Object.assign

With {...newValue}

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

No previous run results

Autogenerated LLM Summary (model gemma2:9b, generated one year ago):