Robot Framework MAC Address test and validation - linux

Question

I run Robot Framework test and it fails me everytime, even I get 1 line or so.
Here is the terminal output for cat command:
RobotFramework:~$ cat macaddresses.txt | grep -o -E '([[:xdigit:]]{1,2}:){5}[[:xdigit:]]{1,2}' | head -n 1
00:01:c0:24:a3:3b
Here is latest Example:
Check MAC Addresses
${macaddress}= Execute Command ifconfig | grep -o -E '([[:xdigit:]]{1,2}:){5}[[:xdigit:]]{1,2}' >> macaddresses.txt
${checkmac}= Execute Command cat macaddresses.txt | grep -o -E '([[:xdigit:]]{1,2}:){5}[[:xdigit:]]{1,2}' | head -n 1
Should Contain ${checkmac} ([[:xdigit:]]{1,2}:){5}[[:xdigit:]]{1,2}
Set Test Message ${checkmac}
If I run it straight from cmd when connected with SSH it works fine and it prints one line of MAC Addressess and that should be fine?
But still I get fail everytime
And here is fail results:
Test MAC Addresses | FAIL |
'00:01:c0:24:a3:3b' does not contain '([[:xdigit:]]{1,2}:){5}[[:xdigit:]]{1,2}'
Debugging Log:
20230124 20:08:16.397 : INFO : ${checkmac} = 00:01:c0:24:a3:3b
20230124 20:08:16.398 : FAIL : '00:01:c0:24:a3:3b' does not contain '([[:xdigit:]]{1,2}:){5}[[:xdigit:]]{1,2}'
Edit:
Also tried Keyword Should Match Regexp
Should Match Regexp ${checkmac} ([[:xdigit:]]{1,2}:){5}[[:xdigit:]]{1,2}
And got error:
20230124 20:24:29.521 : FAIL : '00:01:c0:24:a3:3b' does not match '([[:xdigit:]]{1,2}:){5}[[:xdigit:]]{1,2}'

Answer 1

Well, grep uses a different representation for hex numbers, as you did used :xdigit:. I did not researched, but this looks like a non-standard for Regular Expressions (and first time I see it).
However, I experimented in https://regex101.com/ using Python mode, because that is what Robot Framework uses, and got the following result:
([\d|[a-f]{1,2}:){5}([\d|[a-f]{1,2})
As you can see, each hex pair is constructed with any digit or a-f letters.
This can be validated, with the following Robot Framework test case:
*** Test Cases ***
Test RegEx
${input}= Set Variable 00:01:c0:24:a3:3b
${regex}= Set Variable ([\\d|[a-f]{1,2}:){5}([\\d|[a-f]{1,2})
${result}= Should Match Regexp ${input} ${regex}
Here is the execution log:
Starting test: Test Timeouts.Test RegEx
20230124 21:22:23.128 : INFO : ${input} = 00:01:c0:24:a3:3b
20230124 21:22:23.130 : INFO : ${regex} = ([\d|[a-f]{1,2}:){5}([\d|[a-f]{1,2})
20230124 21:22:23.132 : INFO : ${result} = ['00:01:c0:24:a3:3b', 'a3:', '3b']
Ending test: Test Timeouts.Test RegEx