eclass/tests: Add a benchmark for python-utils-r1

Initial timings on my system:

```
 * Timing _python_set_impls
real 1463 it/s
user 1886 it/s
```

Signed-off-by: Michał Górny <mgorny@gentoo.org>

1 files changed, 53 insertions, 0 deletions

diff --git a/eclass/tests/python-utils-bench.sh b/eclass/tests/python-utils-bench.sh
new file mode 100755
index 000000000000..7f27adef5509
--- /dev/null
+++ b/eclass/tests/python-utils-bench.sh
@@ -0,0 +1,53 @@
+#!/bin/bash
+# Copyright 2023 Gentoo Authors
+# Distributed under the terms of the GNU General Public License v2
+
+EAPI=8
+source tests-common.sh || exit
+
+export LC_ALL=C
+
+ITERATIONS=10000
+RUNS=3
+
+doit() {
+	local i
+	for (( i = 0; i < ITERATIONS; i++ )); do
+		"${@}"
+	done
+}
+
+timeit() {
+	local real=()
+	local user=()
+	local x vr avg
+
+	einfo "Timing ${*}"
+	for (( x = 0; x < RUNS; x++ )); do
+		while read tt tv; do
+			case ${tt} in
+				real) real+=( ${tv} );;
+				user) user+=( ${tv} );;
+			esac
+		done < <( ( time -p doit "${@}" ) 2>&1 )
+	done
+
+	[[ ${#real[@]} == ${RUNS} ]] || die "Did not get ${RUNS} real times"
+	[[ ${#user[@]} == ${RUNS} ]] || die "Did not get ${RUNS} user times"
+
+	local xr avg
+	for x in real user; do
+		xr="${x}[*]"
+		avg=$(dc -S 3 -e "${ITERATIONS} ${RUNS} * ${!xr} + + / p")
+
+		printf '%s %4.0f it/s\n' "${x}" "${avg}"
+	done
+}
+
+PYTHON_COMPAT=( python3_{10..12} pypy3 )
+
+inherit python-utils-r1
+
+timeit _python_set_impls
+
+texit