Benchmark: Is in DOM .isConnected

HTML Preparation code:

<div id="test-div"></div>

Script Preparation code:

function isInDOM1(oHTMLElement) {                                   
  if (oHTMLElement === document.body || oHTMLElement === document ) {
    return true;
  } else {
    try {
      return document.body.contains(oHTMLElement);
    } catch(ex) {
      // Sometimes in Firefox element is anonymous div around input.
      // Throws error "TypeError: Argument 1 of Node.contains does not implement interface Node"
      // See https://bugzilla.mozilla.org/show_bug.cgi?id=208427
      return false;
    }
  }
}

function isInDOM2(oHTMLElement) {                                   
  var root = oHTMLElement.ownerDocument; 
  if (!root) { return false; }
  
  if ( oHTMLElement.ownerDocument.documentElement === document.documentElement ){ return true; }

  return false;
}

function domIsConnected(oHTMLElement) {                                   
  return oHTMLElement.isConnected; 
}
var div = document.getElementById('test-div');

Tests:

isInDOM1
isInDOM1(div);
isInDOM2
isInDOM2(div);
isConnected(div);
domIsConnected(div);

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
isInDOM1
isInDOM2
isConnected(div);

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: one year ago)

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:132.0) Gecko/20100101 Firefox/132.0

Browser/OS: Firefox 132 on Windows

View result in a separate tab

Test name	Executions per second
isInDOM1	15386036.0 Ops/sec
isInDOM2	18895038.0 Ops/sec
isConnected(div);	930231872.0 Ops/sec

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

LLMs can make mistakes. Check important info.

Let's break down the provided benchmark and explain what's being tested.

**Benchmark Overview**

The benchmark is designed to measure the performance of JavaScript functions that check if an element is connected to the DOM (Document Object Model). The test cases focus on three different approaches:

1. `isInDOM1`
2. `isInDOM2`
3. `domIsConnected`

**Approach 1: `isInDOM1`**

The first approach checks if the element is equal to either the document body or the document object itself. This method has a straightforward implementation but can be problematic in certain cases, such as when dealing with anonymous elements that are wrapped around input fields.

```javascript
function isInDOM1(oHTMLElement) {
  if (oHTMLElement === document.body || oHTMLElement === document ) {
    return true;
  } else {
    try {
      return document.body.contains(oHTMLElement);
    } catch(ex) {
      // Handle Firefox-specific issue where Node.contains throws an error
      return false;
    }
  }
}
```

**Pros:**

* Simple and easy to understand

**Cons:**

* Can be brittle and fail in certain edge cases (e.g., anonymous elements)

**Approach 2: `isInDOM2`**

The second approach uses the owner document property of an element to determine if it's connected to the DOM. This method is more robust than the first one but still has its limitations.

```javascript
function isInDOM2(oHTMLElement) {
  var root = oHTMLElement.ownerDocument;
  if (!root) {
    return false;
  }
  // Check if the element is a direct child of the document's root element
  if (oHTMLElement.ownerDocument.documentElement === document.documentElement) {
    return true;
  }
  return false;
}
```

**Pros:**

* More robust than `isInDOM1` but still simple

**Cons:**

* May not cover all edge cases (e.g., elements with multiple parent nodes)

**Approach 3: `domIsConnected`**

The third approach simply calls the built-in `connected` property of an element, which is a part of the DOM specification. This method is likely to be the most accurate and efficient.

```javascript
function domIsConnected(oHTMLElement) {
  return oHTMLElement.isConnected;
}
```

**Pros:**

* Most accurate and efficient

**Cons:**

* None, as it's based on the standard DOM specification

**Library Usage**

The test case uses the `document` object, which is a built-in part of the DOM. The `document` object provides access to various elements and methods for interacting with web pages.

**Special JS Features/Syntax**

There are no special JavaScript features or syntax used in this benchmark that aren't covered by standard DOM specification.

**Other Alternatives**

If you wanted to optimize these approaches, here are some alternative strategies:

1. Use a more efficient algorithm: For example, instead of using `document.body.contains(oHTMLElement)` in `isInDOM1`, use `oHTMLElement.parentNode === null` to check if the element is not a child of any other element.
2. Cache results: If you know that the DOM is unlikely to change frequently, you could cache the results of `domIsConnected` calls for each element.
3. Use a more robust data structure: Instead of using a simple boolean value to represent whether an element is connected to the DOM, consider using a more sophisticated data structure like a graph or a tree.

Keep in mind that these optimizations are unlikely to provide significant performance benefits unless you're dealing with extremely large datasets or performance-critical code.

Related benchmarks:

Is in DOM .isConnected (version: 0)

Check if given element is in dom

Comparing performance of: isInDOM1 vs isInDOM2 vs isConnected(div);

Created: 3 years ago by: Guest

Jump to the latest result

isInDOM1

isInDOM2

isConnected(div);

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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