better error messages in the summary if reference file is missing?

[u-fischer]

The following is the output of small test setup: In testfiles are the tests a, b, c. The reference file for b is missing. In another testfolder with its own config is test d. The result of the check is then

$ l3build check
Running l3build with target "check" with configuration build
Running checks on
  a (1/3)
  b (2/3)
Error: failed to find any reference or expectation file for b!
Running l3build with target "check" with configuration config-extra
Running checks on
  d (1/1)

  All checks passed

Failed tests for configuration build:

  Check failed with difference files

As can be seen test c wasn't checked, and the summary doesn't say clearly that not all tests were checked, and it also doesn't say at which test the tests stopped.

[josephwright]

I think this is more of a bug

[FrankMittelbach]

well it is correct that there are no files that show diffs and there was no test made, ie there was no failed test either so it is kind of correct what it shows, it only forgets to tell you why it stopped. So I was trying to be kind and call it enhancing the product :-)