[codex] add python test infrastructure #45

	# gitxtend CI — gates every PR to main.
	#
	# HOOK PARITY: this pipeline is mirrored by .githooks/pre-push. When editing the
	# steps here, update the hook to match (and vice-versa).
	name: ci

	on:
	push:
	branches: [main]
	pull_request:
	branches: [main]

	env:
	CARGO_TERM_COLOR: always

	jobs:
	check:
	name: fmt + clippy + test (core) + build (python)
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@v4
	- uses: dtolnay/rust-toolchain@stable
	with:
	components: rustfmt, clippy
	- uses: Swatinem/rust-cache@v2

	- name: rustfmt
	run: cargo fmt --all --check

	# The pure-Rust core (no PyO3 / no libpython): the M1 read methods live here.
	- name: clippy (core)
	run: cargo clippy --no-default-features --all-targets -- -D warnings
	- name: test (core)
	run: cargo test --no-default-features

	# The PyO3 wheel surface. `extension-module` links no libpython, so it
	# builds on CI without python-dev.
	- name: clippy (python)
	run: cargo clippy --features extension-module -- -D warnings
	- name: build (python)
	run: cargo build --features extension-module

	python-e2e:
	name: maturin build + Python E2E vs git
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@v4
	- uses: dtolnay/rust-toolchain@stable
	- uses: Swatinem/rust-cache@v2
	- uses: actions/setup-python@v5
	with:
	python-version: "3.12"
	- name: build wheel + run the E2E suite (the compiled module vs the real git CLI)
	run: \|
	python -m venv .venv
	.venv/bin/pip install -q maturin
	.venv/bin/maturin develop --release --extras dev
	.venv/bin/python -m pytest python/tests/ --cov=gitxtend --cov-fail-under=80

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