example.sh

#!/bin/bash
declare -a TEST_NAMES_FROM_BOOT

read_test_from_boot() {
    # Check if test names were passed as boot parameter.
    # We expect `run_tests` to be a comma-separated list of test names.
    IFS=',' read -r -a TEST_NAMES_FROM_BOOT <<< \
        "$(sed -n 's/.*run_tests=\([^ ]*\).*/\1/p' /tmp/a)"

    echo "${TEST_NAMES_FROM_BOOT[@]}"
}

# Expect 2 tests
echo "BOOT_IMAGE=(hd0,gpt2)/vmlinuz-5.19.11-300.fc37.x86_64 root=UUID=ac6e459c-7981-469d-916a-58ed2b23a3ef ro rootflags=subvol=root rd.luks.uuid=luks-e2fb3dac-2da5-4503-a4b8-b55de838800a rhgb quiet run_tests=test_progs,test_progs2" > /tmp/a

read_test_from_boot
echo "${#TEST_NAMES_FROM_BOOT[@]}"

# Expect 0 test
echo "BOOT_IMAGE=(hd0,gpt2)/vmlinuz-5.19.11-300.fc37.x86_64 root=UUID=ac6e459c-7981-469d-916a-58ed2b23a3ef ro rootflags=subvol=root rd.luks.uuid=luks-e2fb3dac-2da5-4503-a4b8-b55de838800a rhgb quiet  abc" > /tmp/a

read_test_from_boot
echo "${#TEST_NAMES_FROM_BOOT[@]}"

# Expect 2 tests, some trailing content
echo "BOOT_IMAGE=(hd0,gpt2)/vmlinuz-5.19.11-300.fc37.x86_64 root=UUID=ac6e459c-7981-469d-916a-58ed2b23a3ef ro rootflags=subvol=root rd.luks.uuid=luks-e2fb3dac-2da5-4503-a4b8-b55de838800a rhgb quiet run_tests=test_progs,test_progs2 abc" > /tmp/a

read_test_from_boot
echo "${#TEST_NAMES_FROM_BOOT[@]}"

$ /tmp/example.sh
test_progs test_progs2
2

0
test_progs test_progs2
2