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+# Copyright 2026 Gentoo Authors
+# Distributed under the terms of the GNU General Public License v2
+
+# @ECLASS: stainless-python.eclass
+# @MAINTAINER:
+# Florian Albrechtskirchinger <falbrechtskirchinger@gmail.com>
+# @AUTHOR:
+# Florian Albrechtskirchinger <falbrechtskirchinger@gmail.com>
+# @SUPPORTED_EAPIS: 8 9
+# @BLURB: Handle Python SDKs generated via Stainless.
+# @DESCRIPTION:
+# The stainless-python eclass manages the building and testing of Python SDKs
+# generated via Stainless.
+# It automates fetching the OpenAPI spec, provisioning the steady mock server
+# from local npm packages, and managing the background mock server process
+# lifecycle during tests.
+
+case ${EAPI} in
+	8|9) ;;
+	*) die "${ECLASS}: EAPI ${EAPI:-0} not supported" ;;
+esac
+
+if [[ ! ${_STAINLESS_PYTHON_ECLASS} ]]; then
+_STAINLESS_PYTHON_ECLASS=1
+
+inherit distutils-r1
+
+# @ECLASS_VARIABLE: STAINLESS_SPEC_BASE_URI
+# @PRE_INHERIT
+# @DESCRIPTION:
+# The base URI for Stainless SDK OpenAPI spec files.
+: "${STAINLESS_SPEC_BASE_URI:=https://storage.googleapis.com/stainless-sdk-openapi-specs}"
+
+# @ECLASS_VARIABLE: STAINLESS_SPEC_PATH
+# @PRE_INHERIT
+# @DEFAULT_UNSET
+# @REQUIRED
+# @DESCRIPTION:
+# The path of the OpenAPI spec file relative to ${STAINLESS_SPEC_BASE_URI}.
+
+# @ECLASS_VARIABLE: STAINLESS_SPEC_DISTNAME
+# @PRE_INHERIT
+# @DESCRIPTION:
+# The target filename of the OpenAPI spec file in ${DISTDIR}.
+: "${STAINLESS_SPEC_DISTNAME:=${PN}-openapi-spec-${PV}.yml}"
+
+# @ECLASS_VARIABLE: STAINLESS_MOCK_SERVER_VERSION
+# @PRE_INHERIT
+# @DEFAULT_UNSET
+# @REQUIRED
+# @DESCRIPTION:
+# The version string of the mock server.
+
+# @ECLASS_VARIABLE: STAINLESS_MOCK_SERVER_PACKAGE_JSON
+# @PRE_INHERIT
+# @DEFAULT_UNSET
+# @REQUIRED
+# @DESCRIPTION:
+# The full path to the mock server package.json.
+
+# @ECLASS_VARIABLE: STAINLESS_MOCK_SERVER_PACKAGE_LOCK_JSON
+# @PRE_INHERIT
+# @DESCRIPTION:
+# The full path to the mock server package-lock.json.
+: "${STAINLESS_MOCK_SERVER_PACKAGE_LOCK_JSON:=${STAINLESS_MOCK_SERVER_PACKAGE_JSON%.json}-lock.json}"
+
+# @ECLASS_VARIABLE: STAINLESS_MOCK_SERVER_PORT
+# @DESCRIPTION:
+# The requested port for the mock server. 0 to bind to a random available port.
+: "${STAINLESS_MOCK_SERVER_PORT:=0}"
+
+# @ECLASS_VARIABLE: STAINLESS_MOCK_SERVER_EXTRA_ARGS
+# @DESCRIPTION:
+# Additional arguments to pass to the mock server.
+STAINLESS_MOCK_SERVER_EXTRA_ARGS=()
+
+# @ECLASS_VARIABLE: STAINLESS_MOCK_SERVER_DISTFILES
+# @INTERNAL
+# @DESCRIPTION:
+# The array of npm packages for the mock server.
+STAINLESS_MOCK_SERVER_DISTFILES=()
+
+# @ECLASS_VARIABLE: STAINLESS_MOCK_SERVER_DIR
+# @INTERNAL
+# @DESCRIPTION:
+# The full path to the mock server directory.
+: "${STAINLESS_MOCK_SERVER_DIR:=${WORKDIR}/stainless-mock-server}"
+
+# @ECLASS_VARIABLE: STAINLESS_MOCK_SERVER_EXEC
+# @INTERNAL
+# @DESCRIPTION:
+# The full path to the mock server executable.
+: "${STAINLESS_MOCK_SERVER_EXEC:=${STAINLESS_MOCK_SERVER_DIR}/node_modules/.bin/steady}"
+
+# @ECLASS_VARIABLE: STAINLESS_MOCK_SERVER_PID
+# @INTERNAL
+# @DESCRIPTION:
+# The PID assigned to the mock server.
+
+# @ECLASS_VARIABLE: STAINLESS_MOCK_SERVER_PORT_ACTUAL
+# @INTERNAL
+# @DESCRIPTION:
+# The port the mock server actually bound to.
+
+_stainless_set_globals() {
+	[[ -n ${STAINLESS_SPEC_PATH} ]] ||
+		die "STAINLESS_SPEC_PATH undefined."
+	[[ -n ${STAINLESS_MOCK_SERVER_VERSION} ]] ||
+		die "STAINLESS_MOCK_SERVER_VERSION undefined."
+	[[ -n ${STAINLESS_MOCK_SERVER_PACKAGE_JSON} ]] ||
+		die "STAINLESS_MOCK_SERVER_PACKAGE_JSON undefined."
+
+	local stdy_base_uri="https://registry.npmjs.org/@stdy"
+	local stdy_pv="${STAINLESS_MOCK_SERVER_VERSION}"
+
+	SRC_URI="
+		test? (
+			${STAINLESS_SPEC_BASE_URI}/${STAINLESS_SPEC_PATH}
+				-> ${STAINLESS_SPEC_DISTNAME}
+
+			${stdy_base_uri}/cli/-/cli-${stdy_pv}.tgz
+				-> @stdy-cli-cli-${stdy_pv}.tgz
+
+			amd64? (
+				${stdy_base_uri}/cli-linux-x64/-/cli-linux-x64-${stdy_pv}.tgz
+					-> @stdy-cli-linux-x64-cli-linux-x64-${stdy_pv}.tgz
+			)
+
+			arm64? (
+				${stdy_base_uri}/cli-linux-arm64/-/cli-linux-arm64-${stdy_pv}.tgz
+					-> @stdy-cli-linux-arm64-cli-linux-arm64-${stdy_pv}.tgz
+			)
+		)
+	"
+
+	STAINLESS_MOCK_SERVER_DISTFILES=(
+		"@stdy-cli-cli-${stdy_pv}.tgz"
+		"@stdy-cli-linux-x64-cli-linux-x64-${stdy_pv}.tgz"
+		"@stdy-cli-linux-arm64-cli-linux-arm64-${stdy_pv}.tgz"
+	)
+	readonly STAINLESS_MOCK_SERVER_DISTFILES
+
+	BDEPEND="
+		test? (
+			net-libs/nodejs[npm]
+			net-misc/curl
+			sys-apps/iproute2
+		)
+	"
+}
+_stainless_set_globals
+unset -f _stainless_set_globals
+
+# @FUNCTION: stainless_setup_mock_server
+# @USAGE:
+# @DESCRIPTION:
+# Prepare the mock server by populating the npm cache and installing the npm
+# packages.
+stainless_setup_mock_server() {
+	einfo "Populating npm cache ..."
+
+	local -x npm_config_offline="true"
+	local -x npm_config_audit="false"
+	local -x npm_config_fund="false"
+	local -x npm_config_cache="${WORKDIR}/stainless-npm-cache"
+	mkdir -p "${npm_config_cache}" || die
+
+	for f in "${STAINLESS_MOCK_SERVER_DISTFILES[@]}"; do
+		[[ -e ${DISTDIR}/${f} ]] || continue
+		if ! npm cache add "${DISTDIR}/${f}" &>"${T}/stainless-npm-cache-add.log"; then
+			eerror "npm cache add '${f}' failed:"
+			cat "${T}/stainless-npm-cache-add.log"
+			die "npm cache add '${f}' failed"
+		fi
+	done
+
+	einfo "Installing mock server ..."
+
+	mkdir -p "${STAINLESS_MOCK_SERVER_DIR}" || die
+
+	cp "${STAINLESS_MOCK_SERVER_PACKAGE_JSON}" \
+		"${STAINLESS_MOCK_SERVER_DIR}/package.json" || die
+	cp "${STAINLESS_MOCK_SERVER_PACKAGE_LOCK_JSON}" \
+		"${STAINLESS_MOCK_SERVER_DIR}/package-lock.json" || die
+
+	pushd "${STAINLESS_MOCK_SERVER_DIR}" >/dev/null || die
+	if ! npm ci &>"${T}/stainless-npm-ci.log"; then
+		eerror "npm ci failed:"
+		cat "${T}/stainless-npm-ci.log"
+		die "npm ci failed"
+	fi
+	popd >/dev/null || die
+
+	[[ -x ${STAINLESS_MOCK_SERVER_EXEC} ]] || die
+}
+
+# @FUNCTION: _stainless_read_cmdline
+# @USAGE: <pid|'self'> <out_var_name>
+# @INTERNAL
+# @DESCRIPTION:
+# Read /proc/<pid|'self'>/cmdline into the provided array variable.
+_stainless_read_cmdline() {
+	(( ${#} == 2 )) || die "Usage: ${FUNCNAME} <pid|'self'> <out_var_name>"
+
+	local pid="${1}"
+	local -n out_var="${2}"
+
+	readarray -d '' out_var <"/proc/${pid}/cmdline" 2>/dev/null || die
+}
+
+# @FUNCTION: _stainless_is_mock_server_running
+# @USAGE:
+# @INTERNAL
+# @DESCRIPTION:
+# Check if the mock server is running.
+_stainless_is_mock_server_running() {
+	[[ -n ${STAINLESS_MOCK_SERVER_PID} ]] || die
+
+	kill -0 "${STAINLESS_MOCK_SERVER_PID}" 2>/dev/null || return 1
+
+	local -a args
+	_stainless_read_cmdline "${STAINLESS_MOCK_SERVER_PID}" args
+
+	# Check args[1] (native) or args[2] (QEMU user-mode emulation)
+	[[ ${args[1]} == "${STAINLESS_MOCK_SERVER_EXEC}" ||
+		${args[2]} == "${STAINLESS_MOCK_SERVER_EXEC}" ]]
+}
+
+# @FUNCTION: _stainless_mock_server_health_check
+# @USAGE:
+# @INTERNAL
+# @DESCRIPTION:
+# Call the mock server health check endpoint.
+_stainless_mock_server_health_check() {
+	local base_url="http://127.0.0.1:${STAINLESS_MOCK_SERVER_PORT_ACTUAL}"
+	curl -sf "${base_url}/_x-steady/health" &>/dev/null
+}
+
+# @FUNCTION: _stainless_wait_for_mock_server
+# @USAGE:
+# @INTERNAL
+# @DESCRIPTION:
+# Wait for the mock server to start.
+_stainless_wait_for_mock_server() {
+	[[ -n ${STAINLESS_MOCK_SERVER_PID} ]] || die
+
+	local -a self_args mock_args
+	_stainless_read_cmdline self self_args
+
+	# 30s timeout (300 attempts with 0.1s waits)
+	local attempts=0 ready=0
+	while (( attempts < 300 )); do
+		# We can arrive here between fork() & execve()
+		# Wait for Bash to spawn the mock server
+		if [[ -n ${mock_args[*]} && ${self_args[*]} != "${mock_args[*]}" ]]; then
+			if ! _stainless_is_mock_server_running; then
+				eerror "Mock server exited during startup:"
+				cat "${T}/stainless-steady.log"
+				die "Mock server exited during startup"
+			fi
+
+			# Discover actual port
+			if [[ -z ${STAINLESS_MOCK_SERVER_PORT_ACTUAL} ]]; then
+				if (( STAINLESS_MOCK_SERVER_PORT == 0 )); then
+					local -a pids
+					readarray -t pids \
+						< <(pgrep -P "${STAINLESS_MOCK_SERVER_PID}" 2>/dev/null)
+
+					if (( ${#pids[@]} > 1 )); then
+						die "Mock server unexpectedly spawned multiple child processes"
+					elif (( ${#pids[@]} == 1 )); then
+						local port
+						port=$(ss -Hntlp 2>/dev/null | awk -v pid="${pids[0]}" \
+							'$0 ~ "pid="pid"," {split($4, a, ":"); print a[length(a)]}')
+						if [[ -n ${port} ]]; then
+							STAINLESS_MOCK_SERVER_PORT_ACTUAL=${port}
+						fi
+					fi
+				else
+					STAINLESS_MOCK_SERVER_PORT_ACTUAL=${STAINLESS_MOCK_SERVER_PORT}
+				fi
+			fi
+
+			# Confirm startup by connecting to health check endpoint
+			if [[ -n ${STAINLESS_MOCK_SERVER_PORT_ACTUAL} ]]; then
+				if _stainless_mock_server_health_check; then
+					ready=1
+					break
+				fi
+			fi
+		fi
+
+		(( attempts++ ))
+		sleep 0.1
+
+		_stainless_read_cmdline "${STAINLESS_MOCK_SERVER_PID}" mock_args
+	done
+
+	if (( ! ready )); then
+		# Note: Possible sign of failed port discovery
+		eerror "Timed out waiting for mock server to start:"
+		cat "${T}/stainless-steady.log"
+		die "Timed out waiting for mock server to start"
+	fi
+}
+
+# @FUNCTION: stainless_start_mock_server
+# @USAGE:
+# @DESCRIPTION:
+# Start the mock server and wait for it to become ready.
+stainless_start_mock_server() {
+	if (( STAINLESS_MOCK_SERVER_PORT != 0 )); then
+		if _stainless_mock_server_health_check; then
+			die "Mock server address already in use"
+		fi
+	fi
+
+	einfo "Starting mock server ..."
+
+	# Replicate the logic from scripts/mock --daemon
+	"${STAINLESS_MOCK_SERVER_EXEC}" \
+		--host 127.0.0.1 -p "${STAINLESS_MOCK_SERVER_PORT}" \
+		--validator-form-array-format=brackets \
+		--validator-query-array-format=brackets \
+		--validator-form-object-format=brackets \
+		--validator-query-object-format=brackets \
+		"${STAINLESS_MOCK_SERVER_EXTRA_ARGS[@]}" \
+		"${DISTDIR}/${STAINLESS_SPEC_DISTNAME}" &>"${T}/stainless-steady.log" &
+	STAINLESS_MOCK_SERVER_PID=${!}
+
+	_stainless_wait_for_mock_server
+
+	einfo "Mock server ready"
+}
+
+# @FUNCTION: stainless_stop_mock_server
+# @USAGE:
+# @DESCRIPTION:
+# Stop the mock server.
+stainless_stop_mock_server() {
+	[[ -n ${STAINLESS_MOCK_SERVER_PID} ]] || die
+
+	if _stainless_is_mock_server_running; then
+		einfo "Stopping mock server ..."
+		kill "${STAINLESS_MOCK_SERVER_PID}" || die
+		wait "${STAINLESS_MOCK_SERVER_PID}" 2>/dev/null
+	fi
+}
+
+# @FUNCTION: stainless-python_pkg_setup
+# @DESCRIPTION:
+# Abort if testing is enabled on an architecture unsupported by the mock server.
+stainless-python_pkg_setup() {
+	if use test && ! { use amd64 || use arm64; }; then
+		die "Tests are only supported on amd64 and arm64"
+	fi
+}
+
+# @FUNCTION: stainless-python_src_unpack
+# @USAGE:
+# @DESCRIPTION:
+# Implement unpacking of dist files, skipping the mock server npm packages,
+# and run deferred validation of the mock server version.
+stainless-python_src_unpack() {
+	# Validate mock server version:
+	# Ensure STAINLESS_MOCK_SERVER_VERSION matches package.json
+	local json expected_pv
+	json=$(<"${STAINLESS_MOCK_SERVER_PACKAGE_JSON}") || die
+
+	[[ ${json} =~ \"@stdy/cli\"[[:space:]]*:[[:space:]]*\"([^\"]+)\" ]] &&
+		expected_pv=${BASH_REMATCH[1]}
+
+	[[ -n ${expected_pv} ]] ||
+		die "Expected '@stdy/cli' dependency declaration in package.json"
+
+	[[ ${STAINLESS_MOCK_SERVER_VERSION} == "${expected_pv}" ]] ||
+		die "Mock server version mismatch:" \
+			"'${STAINLESS_MOCK_SERVER_VERSION}' (from var) !=" \
+			"'${expected_pv}' (from package.json)"
+
+	for f in ${A}; do
+		! has "${f}" "${STAINLESS_MOCK_SERVER_DISTFILES[@]}" && unpack "${f}"
+	done
+}
+
+# @FUNCTION: stainless-python_src_test
+# @USAGE:
+# @DESCRIPTION:
+# Implement the mock server setup, startup, test run, and shutdown logic.
+stainless-python_src_test() {
+	stainless_setup_mock_server
+
+	stainless_start_mock_server
+
+	local -x TEST_API_BASE_URL="http://127.0.0.1:${STAINLESS_MOCK_SERVER_PORT_ACTUAL}"
+	nonfatal distutils-r1_src_test
+	local ret=${?}
+
+	stainless_stop_mock_server
+
+	(( ret == 0 )) || die
+}
+
+# @FUNCTION: _stainless_death_cleanup
+# @USAGE:
+# @INTERNAL
+# @DESCRIPTION:
+# Death hook function to gracefully stop a running mock server during abnormal
+# test termination.
+_stainless_death_cleanup() {
+	[[ -n ${STAINLESS_MOCK_SERVER_PID} ]] || return 0
+
+	kill "${STAINLESS_MOCK_SERVER_PID}" 2>/dev/null
+	wait "${STAINLESS_MOCK_SERVER_PID}" 2>/dev/null
+}
+
+has _stainless_death_cleanup "${EBUILD_DEATH_HOOKS}" ||
+	EBUILD_DEATH_HOOKS+=" _stainless_death_cleanup"
+
+EXPORT_FUNCTIONS pkg_setup src_unpack src_test
+
+fi