Can I include a folder relative to the current directory in PATH in Powershell?

Question

I run a lot of node projects and often have binaries located in:

.\node_modules\.bin

...relative to the projects folder. I'd like to be able to have PATH always include these directories, if they exist. I don't want to include other directories, just the one relative to the current directory. I'm familiar with Add-PathVariable from PSCX and other Powershell basics, but how do I include a folder relative to the current dir in PATH?

Edit: as mentioned in the question, already, I expect the path to stay updated as the directory changes. This is not simply asking about how to use pwd.

You should be able to do this by simply adding ".\node_modules\.bin" (you may have to double the backslashes; I'm never quite sure) to the system PATH. — Jeff Zeitlin, Jul 24 '17 at 12:39
@AnsgarWiechers Your comment was rude but you're correct: you can add relative folders to PATH (I didn't realise this). Write it and I'll mark it as correct. — mikemaccana, Jul 24 '17 at 15:06
I consider it due diligence here on SO to actually test the subject of a question *before* asking the question. Particularly for someone with almost 30k rep. I do not consider it rude at all when neglect of said due diligence is pointed out. YMMV. — Ansgar Wiechers, Jul 24 '17 at 19:34
@AnsgarWiechers I considered '.' but just assumed '.' would resolve immediately (ie, that it was static rather than dynamic). Re: due diligence: I wrote a somewhat complex script using `find-string` and `prompt` to do this dynamically before you posted your answer-comment. You could have made the same point more politely, likewise I'd expect better from someone with over 100K karma. — mikemaccana, Jul 25 '17 at 12:39

score 2 · Accepted Answer · edited Jul 25 '17 at 20:22

You can use a relative path in Env:PATH and the binaries found will update dynamically:

Eg:

$env:PATH += ';.\node_modules\.bin'

Or with the PowerShell Community Extensions (PSCX):

Add-PathVariable '.\node_modules\.bin'

Unlike using $(pwd) the . is not immediately resolved to an absolute path, so PATH is always relative to the current working directory.

Testing this:

$ which uuid
C:\Users\username\Documents\myapp\node_modules\.bin\uuid.cmd

Then changing directory, uuid now refers to a program in a different dir:

$ cd ..\blog\
$ which uuid
C:\Users\username\Documents\blog\node_modules\.bin\uuid.cmd

It's also possible to persistently change PATH in the user or system environment:

[Environment]::SetEnvironmentVariable(($env:PATH + ';.'), 'User')

or

[Environment]::SetEnvironmentVariable(($env:PATH + ';.'), 'Machine')

Security note: when entering a command Windows will automatically search all directories in $env:PATH for files with one of the extensions listed in $env:PATHEXT and execute the first match it finds. Depending on where exactly in the search path you placed . that may even supersede system executables.

You may want to take a look at how to use package installed locally in node_modules for alternative approaches.

Can I include a folder relative to the current directory in PATH in Powershell?

1 Answers1