handle negative intermediate value in rgb to hsv calculation #357

	name: Test Valgrind

	# like the Docker tests, but running valgrind only on .c/.h changes.

	on:
	push:
	branches:
	- "**"
	paths:
	- ".github/workflows/test-valgrind.yml"
	- "**.c"
	- "**.h"
	pull_request:
	paths:
	- ".github/workflows/test-valgrind.yml"
	- "**.c"
	- "**.h"
	workflow_dispatch:

	permissions:
	contents: read

	concurrency:
	group: ${{ github.workflow }}-${{ github.ref }}
	cancel-in-progress: true

	jobs:
	build:

	runs-on: ubuntu-latest
	strategy:
	fail-fast: false
	matrix:
	docker: [
	ubuntu-22.04-jammy-amd64-valgrind,
	]
	dockerTag: [main]

	name: ${{ matrix.docker }}

	steps:
	- uses: actions/checkout@v4

	- name: Build system information
	run: python3 .github/workflows/system-info.py

	- name: Docker pull
	run: \|
	docker pull pythonpillow/${{ matrix.docker }}:${{ matrix.dockerTag }}

	- name: Build and Run Valgrind
	run: \|
	# The Pillow user in the docker container is UID 1001
	sudo chown -R 1001 $GITHUB_WORKSPACE
	docker run --name pillow_container -e "PILLOW_VALGRIND_TEST=true" -v $GITHUB_WORKSPACE:/Pillow pythonpillow/${{ matrix.docker }}:${{ matrix.dockerTag }}
	sudo chown -R runner $GITHUB_WORKSPACE

Provide feedback