写入文件时尝试跳过与正则表达式匹配的行，但新文件有额外的新行

Question

这是我在here 提出的一个问题的衍生。

我正在尝试根据输入字典设置一种可以编辑文本文件的方法。这是我目前所拥有的：

info = {'#check here 1':{'action':'read'}, '#check here 2':{'action':'delete'}}

search_pattern = re.compile(r'.*(#.+)')        

    with open(input_file_name, "r") as old_file, open(output_file_name, "w+") as new_file:
        lines = old_file.readlines()

        for line in lines:
            edit_point = search_pattern.search(line)
            if edit_point:
                result = edit_point.group(1)
                if result in info and info[result]["action"] == "insert":#insert new lines to file
                    print("insert information to file")
                    new_file.write("\n".join([str(n) for n in info[result]["new_lines"]]))
                    new_file.write(result)
                elif result in info and info[result]["action"] == "delete":#skip lines with delete action
                    print("found deletion point. skipping line")
                else:#write to file any line with a comment that is not in info
                    new_file.write(line)
            else:#write lines that do not match regex for (#.*)
                new_file.write(line)

基本上，当您提交字典时，程序会遍历文件，搜索 cmets。如果评论在字典中，它将检查相应的操作。如果操作是插入，它会将行写入文件。如果它被删除，它将跳过该行。任何没有注释的行都应该写入新文件。

我的问题是，当我从文件中删除一行时，它们以前所在的位置似乎有额外的新行。例如，如果我有一个列表：

hello world

how are you #keep this
I'm fine #check here 2
whats up

我希望输出是：

hello world

how are you #keep this
whats up

但我有一个空行：

hello world

how are you #check here 2

whats up

我怀疑这是我最后的 else 语句，它将任何与 edit_point 不匹配的行写入文件，在本例中为新行。但是，我的理解是 for 循环应该逐行执行，并且只需执行该行。谁能告诉我我在这里缺少什么？

Answer 1

这看起来有点复杂，您将读取和写入逻辑与处理逻辑混合在一起，这使得很难跟踪正在发生的事情。试试这种方法：

from enum import Enum
from typing import Dict, List


class Action(Enum):
    KEEP = "keep"
    REMOVE = "remove"


definition = {
    "#KEEP": {"action": Action.KEEP},
    "#REMOVE": {"action": Action.REMOVE},
}


def clean_comments(
    lines: List[str], definition: Dict[str, Dict[str, str]]
) -> List[str]:

    # Keep a list of the lines that should be in the output
    output: List[str] = []

    # Loop the lines
    for line in lines:

        # If any of the comments in the definition is found, process further
        if any([comment in line for comment in definition.keys()]):

            # Figure out what to do
            for comment, details in definition.items():
                if comment in line:

                    if details["action"] == Action.KEEP:
                        output.append(line)
                        break

                    elif details["action"] == Action.REMOVE:
                        break

        # Keep all other lines
        else:
            output.append(line)

    return output


# Your data here...
with open("test_input.txt", "r") as f:
    lines = f.readlines()

# Use the function to clean the text
clean_text = "".join(clean_comments(lines, definition))

# Show the output
print(clean_text)

# Write to file
with open("test.txt", "w") as f:
    f.write(clean_text)

输出：

hello world

how are you #KEEP: This line will be kept in the output file
whats up