Achieve this behaviour with the "skip" option

[PointSingularity]

I am migrating from lint-staged/husky, and I am on Windows.

I have this post-merge hook defined:

#!/usr/bin/env sh
. "$(dirname -- "$0")/_/husky.sh"

IFS=$'\n'
PACKAGE_LOCK_REGEX="(^packages\/.*\/package-lock\.json)|(^package-lock\.json)"
PACKAGES=("$(git diff --name-only HEAD@{1} HEAD | grep -E "$PACKAGE_LOCK_REGEX")")

# If there are any package-lock.json files, run npm install in the directory of the package-lock.json file
if [[ ${PACKAGES[@]} ]]; then
  for package in $PACKAGES; do
    echo "📦 $package was changed. Running npm install. "
    DIR=$(dirname package)
    cd "$DIR" && npm install
  done
fi

Is it possible to achieve this behavior in lefthook using the skip option.
I've tried this, but it's definitely not correct:

post-merge:
  commands:
    run-install:
      skip: |
        PACKAGE_LOCK_REGEX="(^packages\/.*\/package-lock\.json)|(^package-lock\.json)"
        PACKAGES=("$(git diff --name-only HEAD@{1} HEAD | grep -E "$PACKAGE_LOCK_REGEX")")
         if [[ ${PACKAGES[@]} ]]; then
           return 0
         else
           return 1
         fi
      run: npm install

[mrexox]

Hey! There is a files option that allows to skip execution if the result of files is empty. I think it can fit your case:

Haven't tested this, so the command may need some edits

# lefthook.yml

post-merge:
  commands:
    run-install:
      files: git diff --name-only HEAD@{1} HEAD | grep -E "(^packages\/.*\/package-lock\.json)|(^package-lock\.json)"
      run: npm install

[PointSingularity]

Ok, here is my 'workflow', on standard Windows 11:

lefthook.mp4

But I tried running it again under WSL (Ubuntu) and it also fails now, but grep works.

Git output:

So now I am really confused 😅

[mrexox]

Wow, I guess I know what is the issue here. In a latest version of lefthook there were added positional arguments to files command. See #461. So, HEAD@{1} probably transforms to HEAD@ which raises an error. I'd suggest a workaround:

# lefthook.yml

post-merge:
  commands:
    run-install:
      files: git diff --name-only HEAD@{1\} HEAD | grep -E "(^packages\/.*\/package-lock\.json)|(^package-lock\.json)"
      run: npm install

This escape of \} should probably work well. But if not, you could try this:

# lefthook.yml

post-merge:
  commands:
    run-install:
      files: git diff --name-only HEAD~1 HEAD | grep -E "(^packages\/.*\/package-lock\.json)|(^package-lock\.json)"
      run: npm install

Hope this helps!

Also, try running git commands with LEFTHOOK_VERBOSE=true ENV variable, so you can see actual commands executed.

[PointSingularity]

Hey, both commands work on WSL, thank you!

Both still fail on Windows, here is the output with the LEFTHOOK_VERBOSE=true:

It is the same for both versions.

[mrexox]

Oh I see, the problem is that for Windows we pass the plain command instead of wrapping it into a sh -c call.

I'm not sure if it's safe to change this since Windows doesn't require sh to be installed for Git (or does it?).

There is a workaround: you can add a small script post-merge-files.sh

# post-merge-files.sh

git diff --name-only HEAD@{1} HEAD | grep -E "(^packages\/.*\/package-lock\.json)|(^package-lock\.json)"

And then use the following way to reference it in files:

# lefthook.yml

post-merge:
  commands:
    run-install:
      files: sh post-merge-files.sh
      run: npm install

This doesn't look cool since it adds an extra file to your project, but I'm not sure about changing the current behavior. It might break flow for existing Windows users that use files option without a pipe and don't have sh installed.

Maybe adding a global option for all commands wrapper might help 🤔

WDYT?

[PointSingularity]

Oh I see, the problem is that for Windows we pass the plain command instead of wrapping it into a sh -c call.

I'm not sure if it's safe to change this since Windows doesn't require sh to be installed for Git (or does it?).

There is a workaround: you can add a small script post-merge-files.sh

# post-merge-files.sh

git diff --name-only HEAD@{1} HEAD | grep -E "(^packages\/.*\/package-lock\.json)|(^package-lock\.json)"

And then use the following way to reference it in files:

# lefthook.yml

post-merge:
  commands:
    run-install:
      files: sh post-merge-files.sh
      run: npm install

This doesn't look cool since it adds an extra file to your project, but I'm not sure about changing the current behavior. It might break flow for existing Windows users that use files option without a pipe and don't have sh installed.

Maybe adding a global option for all commands wrapper might help 🤔

WDYT?

Adding the script works!

From what I know, Windows has no native way of running sh, so you need to have git bash (or WSL, Cygwin etc.) installed to be able to run it, but installing it with git is not a requirement.

Sure it adds a file, but it works 😁

But changing this would be a breaking change, and it does require users to have something installed.

Like you said, maybe adding an optional flag is the best solution.

Thank you again for taking your time to help me!