refactor cutAtComma to eliminate one bounds check #20

	name: build

	on: [push]

	jobs:
	test:
	runs-on: ubuntu-latest
	strategy:
	matrix:
	go-version: [1.22]
	steps:
	- name: Checkout Source
	uses: actions/checkout@v4
	- name: Setup Go ${{ matrix.go-version }}
	uses: actions/setup-go@v4
	with:
	go-version: ${{ matrix.go-version }}
	cache: true
	- name: Display Go version
	run: go version
	- name: Test
	run: go test -v -coverprofile=cover.out ./...
	- name: Upload coverage reports to Codecov
	uses: codecov/[email protected]
	with:
	token: ${{ secrets.CODECOV_TOKEN }}
	slug: jub0bs/cors
	benchmark:
	needs: test
	strategy:
	matrix:
	os: [ubuntu-latest]
	go-version: [1.22]
	name: Benchmark comparison ${{ matrix.os }} @ Go ${{ matrix.go-version }}
	runs-on: ${{ matrix.os }}
	steps:
	- name: Checkout Code (previous)
	uses: actions/checkout@v4
	with:
	ref: ${{ github.base_ref }}
	path: previous
	- name: Checkout Code (new)
	uses: actions/checkout@v4
	with:
	path: new
	- name: Set up Go ${{ matrix.go-version }}
	uses: actions/setup-go@v4
	with:
	go-version: ${{ matrix.go-version }}
	- name: Install benchstat
	run: go install golang.org/x/perf/cmd/benchstat@latest
	- name: Run Benchmark (previous)
	run: \|
	cd previous
	go test -run=^$ -bench=. -count=10 . -benchtime 10000x > benchmark.txt
	- name: Run Benchmark (new)
	run: \|
	cd new
	go test -run=^$ -bench=. -count=10 . -benchtime 10000x > benchmark.txt
	- name: Run benchstat
	# Mostly to compare allocations;
	# measurements of execution speed in GitHub Actions are unreliable.
	run: \|
	benchstat previous/benchmark.txt new/benchmark.txt

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