如何使用Chef::Util::FileEdit函数保留缩进？

Absolutely feasible! You can easily make the inserted line inherit the exact indentation of the regex-matched line by leveraging regex capture groups to grab the leading whitespace from the matched line, then prepending that whitespace to your new content.

Here's a step-by-step breakdown: #

• Modify your regex to capture indentation: Update your pattern to include a capture group for any leading whitespace (spaces or tabs) at the start of the matched line. Use ^(\s*) at the beginning of your regex—this will capture all whitespace before the actual content you're targeting.
• Prepend the captured indentation to your new line: If your insert_line_after_match function supports a callback (common in many scripting contexts like Ruby's FileEdit), you can access the captured indentation and combine it with your new content.

Example Implementation #

Let's adjust your original call to handle indentation properly:

file_xml.insert_line_after_match(/^(\s*)<cookie-path>\/analytics<\/cookie-path>/) do |match_result|
  # Extract the captured indentation from the regex match
  line_indent = match_result[1]
  # Prepend the indentation to your new line content
  "#{line_indent}<cookie-secure>true</cookie-secure>"
end

How this works: #

• The regex ^(\s*)<cookie-path>\/analytics<\/cookie-path> captures all leading whitespace (spaces/tabs) from the line containing your target <cookie-path> element into the first capture group.
• The callback uses that captured whitespace (line_indent) to format the new <cookie-secure> line, ensuring it matches the exact indentation of the line you're inserting after.

If your insert_line_after_match doesn't support callbacks, you can first locate the matched line, extract its indentation manually, then pass the pre-indented string directly to the function. For example:

# First, find the matched line to get its indentation
matched_line = file_xml.grep(/<cookie-path>\/analytics<\/cookie-path>/).first
line_indent = matched_line.match(/^(\s*)/)[1]
# Now insert the pre-indented line
file_xml.insert_line_after_match(/<cookie-path>\/analytics<\/cookie-path>/, "#{line_indent}<cookie-secure>true</cookie-secure>")

This approach ensures your new line blends seamlessly with the existing XML structure, maintaining consistent formatting.

内容的提问来源于stack exchange，提问作者Raamish Malik