Metadata

ID: go-best-practices/bytes-compare-equal

Language: Go

Severity: Warning

Category: Best Practices

Description

In Go, when comparing two byte slices for equality, it is recommended to use bytes.Equal(x, y) instead of bytes.Compare(x, y) == 0.

Here’s why bytes.Equal(x, y) is preferred over bytes.Compare(x, y) == 0:

1. Simplicity and Readability: Using bytes.Equal(x, y) provides a more straightforward and readable way to compare byte slices for equality. It clearly conveys the intention of the condition without needing an additional comparison check.
2. Performance: bytes.Equal(x, y) is optimized for efficiency and performs a quick early exit if the lengths of the slices are not equal. On the other hand, bytes.Compare(x, y) == 0 performs a full lexicographic comparison and is less performant for simple equality checks.
3. Idiomatic Expression: In Go, bytes.Equal(x, y) is the idiomatic way to check if two byte slices are equal. It is widely recognized and understood by Go developers, making your code more maintainable and consistent with the Go ecosystem.

For example, consider the following code snippets:

1
2
3
if bytes.Equal(x, y) {
    // Code block
}

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2
3
if bytes.Compare(x, y) == 0 {
    // Code block
}

Both snippets check if the byte slices x and y are equal. However, the first snippet using bytes.Equal(x, y) is preferred for its simplicity, readability, and potential performance benefits.

By using bytes.Equal(x, y) instead of bytes.Compare(x, y) == 0, you can write cleaner and more efficient code that adheres to Go’s idiomatic style.

Non-Compliant Code Examples

func main() {
    if bytes.Compare(x, y) == 0 {
        
    }
}

Compliant Code Examples

func main() {
    if bytes.Equal(x, y) {
        
    }
}

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