Continuous integration setup
Testing PyVISA in a thorough manner is challenging due to the need to access both a VISA library implementation and actual instruments to test against. In their absence, tests are mostly limited to utility functions and infrastructure. Those limited tests are found at the root of the testsuite package of pyvisa. They are run, along with linters and documentation building on each commit using Github Actions.
Thanks to Keysight tools provided to PyVISA developers, it is also possible to test most capabilities of message based resources. However due to the hardware requirements for the build bots, those tests cannot be set up on conventional hosted CIs platform such as Travis, Azure, Github actions, etc.
Self-hosted builder can be used to run the tests requiring those tools. PyVISA developer have chosen to use Azure Pipelines to run self-hosted runners. This choice was based on the ease of use of Azure and the expected low maintenance the builder should require since the CIs proper is handled through Azure. Github Actions has also been considered but due to security reason, self-hosted runners should not run on forks and Github Actions does not currently provide a way to forbid running self-hosted runners on forks.
An Azure self-hosted runner has been set in place and will remain active till December 2020. This runner can only test TCPIP based resources. A new runner will be set up in the first trimester of 2021 with hopefully capabilities extended to USB::INSTR and GPIB resources.
The setup of the current runner is not perfect and the runner may go offline at times. If this happen, before December 2020, please contact @MatthieuDartiailh on Github.
The current runner runs on Windows and uses conda. Due to the working of the activation scripts on Windows calls to activate or conda activate must be preceded by call.