gh-77065: Add optional keyword-only argument echo_char for getpass.getpass

Doc/library/getpass.rst

@@ -16,7 +16,7 @@
 
 The :mod:`getpass` module provides two functions:
 
-.. function:: getpass(prompt='Password: ', stream=None)
+.. function:: getpass(prompt='Password: ', stream=None, *, echochar=None)
 
    Prompt the user for a password without echoing.  The user is prompted using
    the string *prompt*, which defaults to ``'Password: '``.  On Unix, the
@@ -25,6 +25,12 @@ The :mod:`getpass` module provides two functions:
    (:file:`/dev/tty`) or if that is unavailable to ``sys.stderr`` (this
    argument is ignored on Windows).
 
+   The *echochar* argument controls how user input is displayed while typing.
+   If *echochar* is ``None`` (default), input remains hidden. If *echochar* is
+   a string, each typed character is replaced with the given string.
+   For example, ``echochar='*'`` will display asterisks instead of the actual
+   input.
+
    If echo free input is unavailable getpass() falls back to printing
    a warning message to *stream* and reading from ``sys.stdin`` and
    issuing a :exc:`GetPassWarning`.

Doc/whatsnew/3.14.rst

@@ -558,6 +558,16 @@ getopt
 * Add support for returning intermixed options and non-option arguments in order.
   (Contributed by Serhiy Storchaka in :gh:`126390`.)
 
+
+getpass
+-------
+
+* Support keyboard feedback by :func:`getpass.getpass` via the keyword-only
+  optional argument ``echochar``. Placeholder characters are rendered whenever
+  a character is entered, and removed when a character is deleted.
+  (Contributed by Semyon Moroz in :gh:`77065`.)
+
+
 http
 ----
 

Lib/getpass.py

@@ -1,6 +1,7 @@
 """Utilities to get a password and/or the current user name.
 
-getpass(prompt[, stream]) - Prompt for a password, with echo turned off.
+getpass(prompt[, stream[, echochar]]) - Prompt for a password, with echo
+turned off and optional keyboard feedback.
 getuser() - Get the user name from the environment or password database.
 
 GetPassWarning - This UserWarning is issued when getpass() cannot prevent
@@ -25,13 +26,15 @@
 class GetPassWarning(UserWarning): pass
 
 
-def unix_getpass(prompt='Password: ', stream=None):
+def unix_getpass(prompt='Password: ', stream=None, *, echochar=None):
     """Prompt for a password, with echo turned off.
 
     Args:
       prompt: Written on stream to ask for the input.  Default: 'Password: '
       stream: A writable file object to display the prompt.  Defaults to
               the tty.  If no tty is available defaults to sys.stderr.
+      echochar: A string used to mask input (e.g., '*').  If None, input is
+              hidden.
     Returns:
       The seKr3t input.
     Raises:
@@ -68,12 +71,37 @@ def unix_getpass(prompt='Password: ', stream=None):
                 old = termios.tcgetattr(fd)     # a copy to save
                 new = old[:]
                 new[3] &= ~termios.ECHO  # 3 == 'lflags'
+                if echochar:
+                    new[3] &= ~termios.ICANON
                 tcsetattr_flags = termios.TCSAFLUSH
                 if hasattr(termios, 'TCSASOFT'):
                     tcsetattr_flags |= termios.TCSASOFT
                 try:
                     termios.tcsetattr(fd, tcsetattr_flags, new)
-                    passwd = _raw_input(prompt, stream, input=input)
+                    if not echochar:
+                        passwd = _raw_input(prompt, stream, input=input)
+                        stream.write('\n')
+                        return passwd
+
+                    passwd = ""
+                    stream.write(prompt)
+                    stream.flush()
+                    while True:
+                        char = input.read(1)
+                        if char == '\n' or char == '\r':
+                            break
+                        if char == '\x03':
+                            raise KeyboardInterrupt
+                        if char == '\x7f' or char == '\b':
+                            if echochar and passwd:
+                                stream.write("\b \b" * len(echochar))
+                                stream.flush()
+                            passwd = passwd[:-1]
+                        else:
+                            passwd += char
+                            if echochar:
+                                stream.write(echochar)
+                                stream.flush()
                 finally:
                     termios.tcsetattr(fd, tcsetattr_flags, old)
                     stream.flush()  # issue7208
@@ -93,7 +121,7 @@ def unix_getpass(prompt='Password: ', stream=None):
         return passwd
 
 
-def win_getpass(prompt='Password: ', stream=None):
+def win_getpass(prompt='Password: ', stream=None, *, echochar=None):
     """Prompt for password with echo off, using Windows getwch()."""
     if sys.stdin is not sys.__stdin__:
         return fallback_getpass(prompt, stream)
@@ -108,9 +136,16 @@ def win_getpass(prompt='Password: ', stream=None):
         if c == '\003':
             raise KeyboardInterrupt
         if c == '\b':
+            if echochar and pw:
+                for _ in echochar:
+                    msvcrt.putwch('\b')
+                    msvcrt.putwch(' ')
+                    msvcrt.putwch('\b')
             pw = pw[:-1]
         else:
             pw = pw + c
+            if echochar:
+                msvcrt.putwch(echochar)
     msvcrt.putwch('\r')
     msvcrt.putwch('\n')
     return pw

Misc/NEWS.d/next/Library/2025-02-24-07-08-11.gh-issue-77065.8uW0Wf.rst

@@ -0,0 +1,2 @@
+Add keyword-only optional argument *echochar* for :meth:`getpass.getpass`.
+Patch by Semyon Moroz.