Stuck on an issue?

Lightrun Answers was designed to reduce the constant googling that comes with debugging 3rd party libraries. It collects links to all the places you might be looking at while hunting down a tough bug.

And, if you’re still stuck at the end, we’re happy to hop on a call to see how we can help out.

Command `run` should allow external `diff` drivers on `--show-diff-on-failure`

See original GitHub issue

Currently, pre-commit doesn’t allow external diff drivers to be used when --show-diff-on-failure. This is a convenient feature to have since default diff drivers are not so human readable, especially on trailing whitespace changes.

With default driver:

With a custom (diff-so-fancy) driver specified in the .gitconfig of the user:

In practice, --no-ext-diff shouldn’t be enforced. See https://github.com/pre-commit/pre-commit/blob/main/pre_commit/commands/run.py#L306 .

Issue Analytics

State:
Created a year ago
Comments:5 (3 by maintainers)

Top GitHub Comments

1reaction

asottilecommented, Mar 28, 2022

there’s no pipe there

I’m not changing it, stop arguing you are wasting your time and my time

0reactions

ljmf00commented, Mar 28, 2022

if you want custom behaviour use || (your custom behaviour here && exit 1)

Piping the output is an option, but if we consider that hooks could output a unified diff format in the middle of the output, this is not ideal.

invoking a custom diff tool can hang the program indefinitely while waiting for interaction so it is intentionally avoided

External drivers can even open UI tools, but that’s the user option to do so. What about just allowing custom pagers then? In contrast to external diff drivers, pagers are intended to output on the TTY and check for TTY interactiveness.