1334206 - Try to automatically determine --flavor and --subsuite when running mochitests in a one-click-loaner

Status: NEW

(Testing :: General, defect, P3)

Description

[Andrew Halberstadt [:ahal]]

Currently if you start a one-click loaner with a non-plain flavor or a subsuite, then you also need to specify that --flavor and --subsuite to the mach command. If you don't, there is an unhelpful error about no tests being found.

E.g, this fails:
./mach mochitest devtools/client

but this works:
./mach mochitest -f browser --subsuite devtools devtools/client

When running locally, the build system will find all test paths across all flavors and subsuites given a path to a directory. However, when running in the one-click loaner we don't have that luxury.

I think there are two possibilities here:
1) Try to determine what the flavor/subsuite of the cloned job was and make those the default so the first mach command above works.

2) If that proves to be too hard, make the error messages better so it is obvious that --flavor/--subsuite need to be passed in.