[ros2param] Provide tests for ros2param verbs

[BMarchi]

As the title says, this PR provides a set of tests covering the usage of all the verbs for ros2param

• Linux
• Arch
• Windows
• OSX

Connected to ros2/rclpy#455

[hidmic]

First pass!

[hidmic]

Second pass!

[hidmic]

LGTM but for a few more comments and pending green CI

[hidmic]

LGTM pending one last CI run

[BMarchi]

Yep, lets hope it doesn't hang

[BMarchi]

• Linux
• Arch
• Windows
• OSX

[BMarchi]

Playing around with a Windows VM I was able to get all test running just fine if and only if I run them individually for each rmw_implementation, when I combine them (at least fastrtps, cyclone and connext), some tests hang and return exit code 1 after a sigterm is sent. I wasn't able yet to determine the root cause of this. Any thoughts?

[claireyywang]

Playing around with a Windows VM I was able to get all test running just fine if and only if I run them individually for each rmw_implementation, when I combine them (at least fastrtps, cyclone and connext), some tests hang and return exit code 1 after a sigterm is sent. I wasn't able yet to determine the root cause of this. Any thoughts?

I've encountered similar situation when running CI on another ros2cli PR on windows. It seems like there's no definite fix for it yet according to @nuclearsandwich 's investigation ros2/rclpy#456 and ros2/build_farmer#248

[nuclearsandwich]

I've encountered similar situation when running CI on another ros2cli PR on windows. It seems like there's no definite fix for it yet according to @nuclearsandwich 's investigation ros2/rclpy#456 and ros2/build_cop#248

The hangs in ros2/build_farmer#248 were resolved by eProsima/Fast-DDS#871 and the hung processes were deadlocked requiring a SIGKILL so it is likely something else going on here.

[ivanpauno]

@hidmic I assigned you, so it doesn't appear more in our triage search, I also understand you're planning to follow-up on this.