Sourcing .bashrc from ssh after removing the prompt string check

Question

I have a .bashrc file that needs to be sourced non-interactively. The problem is that on the file there is this return statement preventing from sourcing by code:

[ -z "$PS1" ] && return 

To overcome this without modifying the remote .bashrc file I cat the file, grep out this line and source it as below:

user@host -t "
  source <( echo \"\$(cat /home/release/.bashrc | grep -v \"return\")\" ); 
  alias v; 
  v"

P.S: Had I sourced .bash_profile the results would be the same as if I hadn't sourced it at all.

What I find strange is that if I declare an alias like so:

alias v='cat somefile'

and then run these two commands as previously:

alias v;
v;

I get the following output for each:

alias v='cat somefile'
bash: v: command not found

My question is: If it can see that there is an alias defined, why it won't recognize the command?

Answer 1

From the bash man page

Aliases are not expanded when the shell is not interactive, unless the expand_aliases shell option is set using shopt

when you run a shell script, as you know, it spawns another subshell, runs your script in that shell and returns the output to the current shell. So, the script is running in a non-interactive shell.

Although I wouldn't advise, you can change this behavior, by using the following command:

 shopt -s expand_aliases
 alias v='cat somefile'
 v

and you should see it working. The advice against using it comes from people get lazy and take things for granted in time and forget what they did. And god forbid if you need to give the reins of your systems to new sysadmin when you move to greener pastures. Probably the poor soul will have no clue what you did and shoot himself or herself in the foot. My advice is sticking with simple and widely known/accepted operation principles instead of wildly customized environments.