Use Bytes Buffer String

ID

go.use_bytes_buffer_string

Severity

low

Remediation Complexity

trivial

Remediation Risk

low

Remediation Effort

low

Resource

Code Smell

Language

Go

Tags

CWE:1164, code-smell, readability

Description

Reports string(buf.Bytes()) where buf is a bytes.Buffer or strings.Builder.

Rationale

Both bytes.Buffer and strings.Builder expose a String() method that returns their contents directly, so converting the result of Bytes() to a string allocates a second copy of the data for no reason. The rule fires only when the argument is exactly a no-argument .Bytes() call whose receiver resolves to one of those types; an unresolved receiver is left alone.

import "bytes"

func fn(buf bytes.Buffer) {
    _ = string(buf.Bytes()) // FLAW — use buf.String()
    _ = buf.String()        // OK
}

Remediation

Call the String() method directly instead of converting Bytes() to a string.

References