Rule request: AvoidUsingOutNull

Summary of the new feature

I want PSScriptAnalyzer to flag uses of Out-Null for output suppression so that I can maintain consistent code style and potentially gain minor performance improvements.

Currently, many PowerShell scripts use | Out-Null to suppress command output, but there are alternative approaches like [void], > $null, or assignment to $null that are stylistically preferred by many developers. While the performance difference is minimal, having a consistent approach to output suppression improves code readability and maintainability.

Proposed technical implementation details (optional)

• Rule Name: AvoidUsingOutNull
• Severity: Information (since this is primarily a style preference)
• Category: Style
• Detection: Flag any pipeline that ends with | Out-Null
• Suggested alternatives:
  • [void](command)
  • command > $null
  • $null = command
• Example violation: Get-Process | Out-Null
• Example fix: [void](Get-Process) or Get-Process > $null

The rule should provide informational messages suggesting these alternatives while acknowledging that this is primarily a stylistic choice rather than a critical performance issue.

What is the latest version of PSScriptAnalyzer at the point of writing

1.24.0

找出可比較的 PSScriptAnalyzer 規則及其測試，然後檢查規則名稱、嚴重性、類別、診斷資訊和管線模式是如何表示的。當以 Out-Null 結尾的管線產生帶有建議替代方案的資訊性 Style 診斷，而其他輸出抑制形式不受影響時，即表示完成。