On my machine, this script took about 3.4 seconds, and was responsible
for essentially all of the time taken by the precommit hook.
The script is a faithful 1:1 reimplementation, even the regexes are
identical. And yet, it takes about 0.02 seconds, making the pre-commit
hook lightning fast again. Apparently python is just faster in this
case.
Fun fact:
- Just reading all ~4000 files took bash about 1.2 seconds
- Checking the license took another 1.8 seconds in total
- Checking for math.h took another 0.4 seconds in total
- Checking for '#pragma once' took another 0.4 seconds in total
The timing is highly load-dependent, so they don't exactly add up to 3.4
seconds. However, it's good enough to determine that bash is no longer
fit for the purpose of this script.
Most of the existing lint-ing shell scripts have the ability
to only run on the files which have actually changed.
The new port lint-ing script doesn't have this functionality
unfortunately. This forces us to lint ALL the ports on every
single change to any other file in the system if you have
the pre-commit hook setup for your git clone locally.
Instead we can use pre-commit's feature to only run a hook
if certain files have changed to reduce the situations in
which we would run the Meta/lint-ports.py script.
The bash version takes around 15 seconds to run; that is way too slow.
This python3 version should take less than one second to run. :^)
Also, the script will now also check .py files and .txt CMake files.
This should speed up pre-commit a bit as only files that are staged will
be processed, and clang-format and shellcheck are only invoked once, not
for every file. When no arguments are given (e.g. on CI), it still uses
'git ls-files'.
Problem:
- The first lint check that fails results in all subsequent checks not
being run.
Solution:
- Run all the lint checks aggregating the number of failures.
- Return a non-0 exit code if any have failed.
Problem:
- It is possible for a new test file to be added to the `AK/Tests`
directory without being added to the corresponding
`CMakeLists.txt`. This results in the tests not being run.
Solution:
- As part of CI linting, verify that all the `AK/Tests/Test*.cpp`
files are mentioned in the `CMakeLists.txt`.
