enable() method doesn't work when connection is initialized with 'auto_connect' = False

[VeryVVell]

Description of Issue/Question

When ConnectHandler is initialized without parameter 'auto_connect' all works as expected, but if I submit 'auto_connect' = False to ConnectHandler and invoke establish_connection(), then subsequent enable() fails with error:

ValueError: Failed to enter enable mode. Please ensure you pass the 'secret' argument to ConnectHandler.

Netmiko version

netmiko==4.3.0

Netmiko device_type (if relevant to the issue)

cisco_ios

Steps to Reproduce the Issue

In [26]: params
Out[26]: 
{'device_type': 'cisco_ios',
 'host': '10.50.51.126',
 'username': 'wizard',
 'password': 'sanfra',
 'secret': 'cisco',
 'verbose': True,
 'auto_connect': False}

In [27]: dev = netmiko.ConnectHandler(**params)

In [28]: dev.establish_connection()
SSH connection established to 10.50.51.126:22
Interactive SSH session established

In [29]: dev.enable()

Error Traceback

---------------------------------------------------------------------------
ValueError                                Traceback (most recent call last)
Cell In[25], line 1
----> 1 dev.enable()

File ~/pylabs/venv/lib/python3.10/site-packages/netmiko/cisco_base_connection.py:26, in CiscoBaseConnection.enable(self, cmd, pattern, enable_pattern, check_state, re_flags)
     17 def enable(
     18     self,
     19     cmd: str = "enable",
   (...)
     23     re_flags: int = re.IGNORECASE,
     24 ) -> str:
     25     """Enter enable mode."""
---> 26     return super().enable(
     27         cmd=cmd,
     28         pattern=pattern,
     29         enable_pattern=enable_pattern,
     30         check_state=check_state,
     31         re_flags=re_flags,
     32     )

File ~/pylabs/venv/lib/python3.10/site-packages/netmiko/base_connection.py:2050, in BaseConnection.enable(self, cmd, pattern, enable_pattern, check_state, re_flags)
   2048     else:
   2049         if not self.check_enable_mode():
-> 2050             raise ValueError(msg)
   2052 except NetmikoTimeoutException:
   2053     raise ValueError(msg)

ValueError: Failed to enter enable mode. Please ensure you pass the 'secret' argument to ConnectHandler.

Relevant Python code

params = {
    'device_type': 'cisco_ios',
    'host': '10.50.51.126',
    'username': 'wizard',
    'password': 'sanfra',
    'secret': 'cisco',
    'auto_connect': False,
    'verbose': True,
}

dev = netmiko.ConnectHandler(**params)
dev.establish_connection()
dev.enable()

[ktbyers]

You need to call dev._open() if you are going to bypass the normal connection process (i.e. if you set auto_connect=False).

[ktbyers]

So code should be:

params = {
    'device_type': 'cisco_ios',
    'host': '10.50.51.126',
    'username': 'wizard',
    'password': 'sanfra',
    'secret': 'cisco',
    'auto_connect': False,
    'verbose': True,
}

dev = netmiko.ConnectHandler(**params)
dev._open()
dev.enable()

[VeryVVell]

Thanks a million for your help!