How to combine different coverage files?

[64J0]

Description:

Hello, hope you're good.

I have some tests that run in parallel, and each is responsible for testing a module of the system. I'd like to combine all their coverage files (.xml) into a final single file.

Is it possible when using altcover? If it is, how?

[SteveGilham]

The Merge-OpenCover cmdlet can do this for you in a general case.

If the tests are being run on the exact same set of binaries, it is possible to do

1. instrument once
2. test 1
3. collect
4. test 2
5. collect
6. test 3
7. collect
8. ...

[64J0]

They run in parallel in different virtual machines, but indeed, they are related to the same binaries. Thanks for the fast reply @SteveGilham.

[64J0]

Possibly related: https://stackoverflow.com/questions/23089627/opencover-possible-to-merge-multiple-reports-into-one.

I'm going to start implementing/testing this tomorrow.

[64J0]

I'm reopening this issue since I noticed that this tool documentation is for PowerShell. Does it work in Linux shell as well (like bash, for example)?

[64J0]

Apparently PowerShell works on Linux -> https://learn.microsoft.com/en-us/powershell/scripting/install/installing-powershell-on-linux?view=powershell-7.3

[64J0]

To present an overview of what I'm trying:

• [x] Install and start (pwsh) PowerShell on Linux
• [x] Install AltCover as a global tool (dotnet tool install --global altcover.global --version 8.6.68)
• [x] Use the ImportModule command with altcover ImportModule

But, whenever I try to use the Merge-OpenCover command it throws this error:

Merge-OpenCover: The term 'Merge-OpenCover' is not recognized as a name of a cmdlet, function, script file, or executable program.
Check the spelling of the name, or if a path was included, verify that the path is correct and try again.

[64J0]

Actually, I understood how to use it now, after checking this file:

• https://github.com/SteveGilham/altcover/blob/2afb2c0102c99b5c5d00be7119c5be9a09dbb984/Build/merge-coverage.ps1