Question

I normally write code with tabs but many python libraries use spaces. Is there any way for Notepad++ to automatically detect how the file is formatted and have it automatically switch to using spaces when the file is already formatted that way?

BTW, I know there was already an SO question on how to change Notepad++’s tab format. But it would be better if it automatically changed based on the current file’s formatting.

Answer 1

If you install the “Python Script” plugin for Notepad++, you can write code to automatically switch between tabs and spaces.

Here’s how:

1. In the menu: Plugins -> Python Script -> Configuration, and set Initialization to ATSTARTUP. When Notepad++ starts, the startup.py script will run.

2. Find startup.py and edit it. On my PC its path is c:\Program Files\Notepad++\plugins\PythonScript\scripts\startup.py, add the following code to startup.py.

The function buffer_active() is called every time when you switch tab, and guess_tab() checks whether the text is using tab indent or not. You can show the Python console to debug the code.

def guess_tab(text):
    count = 0
    for line in text.split("\n"):
        indents = line[:len(line)-len(line.lstrip())]
        if "\t" in indents:
            count += 1
    if count > 5: 
        return True
    else:
        return False

def buffer_active(arg):
    editor.setBackSpaceUnIndents(True)
    use_tab = guess_tab(editor.getText())
    editor.setUseTabs(use_tab)
    sys.stderr.write( "setUseTabs %s\n" % use_tab )

notepad.clearCallbacks([NOTIFICATION.BUFFERACTIVATED])    
notepad.callback(buffer_active, [NOTIFICATION.BUFFERACTIVATED])

This is only an example, feel free to make guess_tab() better yourself, maybe use a global dict to cache the result and speedup the callback function.