fixed symbolic link dereference when launching shell

[vvavrychuk]

Without this if we pty.spaw with cwd beeing a symbolic link,
then actually shell will be opened with cwd dereferenced.

[Tyriar]

@vvavrychuk by dereferenced do you mean it follows the cwd? Is this not expected/ideal?

[vvavrychuk]

@Tyriar I mean suppose we have folder A being symbolic link to B. If we pass A as cwd to node-pty then after launch actual cwd will be B.

I am not sure what is ideal, but:

• I needed this to implement change similar to Do not fs.realpath workspace paths so that symlinks are left intact vscode#18837 on vscode terminal
• Maybe if user wants dereference than he can do realpath in advance.
• I tried to start xterm and see that it does not perform dereference

[Tyriar]

@vvavrychuk oh I see. Do you have a link to documentation describing the $PWD environment variable's behavior? Need to make sure this works on macOS and linux. We may also be able to create a unit test for this one.

[vvavrychuk]

I dropped using patch and ended up using mount --bind instead of symbolic links. Problem is that even if we change behavior in VS code, similar thing exists in other software.

[Tyriar]

@vvavrychuk I'm still open to merging this in, I just want to make sure I understand the behavior of $PWD

[Tyriar]

@vvavrychuk I've learned more about this myself over time and got pinged in microsoft/vscode#59291 about it, this is totally the expected behavior as it's how cd works. Thanks for the contribution and sorry about not merging 2 years ago 🙂