The documentation displayed at https://docs.microsoft.com/en-us/dotnet/core/tools/dotnet-test does not match the one that get's shown when you do dotnet test --help.
The webpage states that options go AFTER the project filepath:

The CLI states that options go BEFORE the project filepath:

Also, the project is shown as optional in the webpage and mandatory in the CLI.
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@toqueteos Thanks for pointing that out. We'll investigate and fix it.
Options can go before or after the project file path, so it's just a difference in format between help text and doc.
The help text doesn't put the PROJECT|SOLUTION argument in brackets but the text explains that it could be omitted.
I did find some discrepancies in the options listed in help vs. the doc -- #17264 will fix those.
Thank you! I'll recheck why my test were not running.