post-merge doesn't seem to find files to check

search tried in the issue tracker

yes. a lot.

describe your issue

I want to trigger a custom commit hook on post merge, ideally with a list of of incoming file changes.

Custom hook config:

-   id: run-pbi-tools-post-merge
    name: pbi-tools compile (post merge)
    description: invoke pbi-tools to compile powerbi proj-folders into reports
    entry: run-pbi-tools-post-merge
    language: python
    files: ''                   # all files
    require_serial: true        # no parallel invocation
    verbose: true
    stages: [post-merge]

Client-side repo config:

repos:
- [...]
-   repo: https://github.com/myorg/precommit_hooks
    rev: 0.1.3
    hooks:
    -   id: run-pbi-tools-post-merge

I’ve installed pre-commit for post-merge (pre-commit install -t post-merge), however pre-commit isn’t invoking the hook:

git pull
Updating 87c6d50..f51cb2a
Fast-forward
 trigger.txt | Bin 0 -> 82 bytes
 1 file changed, 0 insertions(+), 0 deletions(-)
 create mode 100644 trigger.txt
pbi-tools compile (post merge).......................(no files to check)Skipped
- hook id: run-pbi-tools-post-merge

I would expect the hook to be invoked for trigger.txt.

I’m getting similar output when manually invoking the hook for trigger.txt:

pre-commit run --verbose --hook-stage post-merge --files trigger.txt
pbi-tools compile (post merge).......................(no files to check)Skipped
- hook id: run-pbi-tools-post-merge

… or for all files:

pre-commit run --verbose --all-files --hook-stage post-merge
pbi-tools compile (post merge).......................(no files to check)Skipped
- hook id: run-pbi-tools-post-merge

Is this a misconception on my end? My use case is running a script on pull to restore meta-data that was split up on commit. Maybe someone could point me towards an example that does something similar? So far I haven’t been able to find any.

pre-commit --version

2.20.0 (running on Windows)

.pre-commit-config.yaml

repos:
- [...]
-   repo: https://github.com/myorg/precommit_hooks
    rev: 0.1.3
    hooks:
    -   id: run-pbi-tools-post-merge

~/.cache/pre-commit/pre-commit.log (if present)

./.

[jangroth]

Update for future readers that might search for issues with post_merge:

This hook can be invoked without file names being submitted by configuring always_run: true in .pre-commit-config.yaml

git pull
Updating 25d7641..629438c
Fast-forward
 trigger.txt | Bin 0 -> 82 bytes
 1 file changed, 0 insertions(+), 0 deletions(-)
 create mode 100644 trigger.txt
pbi-tools compile (post merge)...........................................Passed
- hook id: run-pbi-tools-post-merge
- duration: 0.62s

2022-07-19 09:20:43,820 run_pbi_tools DEBUG Invoking post_merge_handler with Namespace(filenames=[])

[jangroth]

Hi @asottile - thanks for getting back to me.

Let me make myself clear: I think pre-commit is great and I very much appreciate your work. Also, I understand that you are running this in your own time and I have zero expectation for you to sacrifice your time beyond what you are willing to spend on this project.

Maybe in turn you can understand where I was coming from: I had already spent days working with & learning the framework. Only last week I moved to the post-merge bit of my work and yes, I misunderstood the relevance of the paragraph you pointed me to and also did not make the connection between post_checkout (always_run documented) and post_merge (always_run not mentioned). However, not only is this really difficult stuff, I also made an honest effort to solve the problem without having to post an issue here, including spending considerable time here and on SoF. So yes, ‘RTFM’ wasn’t the answer I was hoping for. There might also be a little bit of cultural differences in the mix, what you consider ‘brevity’ in English is a solid 8/10 ‘rudeness’ in German 😃

However, all good from my end, and as I said, I really appreciate your work here.