Allow / as root folder

[julianseeger]

When / is the only common directory of the coverage report, the report generation fails.
The root dir "/" is trimmed at several functions, what leads to a path like "home/somefile.php" which is of course not found and thus not imported to the coverage report (at least not with coverage-html).

This PR fixes this issue and allows coverage reports with "/" as the only common path of the report.
I hope the tests point out the problem.

[sebastianbergmann]

Can we use a stub of PHP_CodeCoverage_Report_Node (using getMockForAbstractClass()) instead of DefaultNode? If not, can you please move the DefaultNode class into a separate file under tests/_files?

[julianseeger]

getMockForAbstractClass mocks every method, so it doesn't seem to be possible to use it and still call the original getPath() method. And the "_files" dir is used in the FilterTest so it's some kind of fixture directory for this test. Are you ok with placing it in the same directory as the NodeTest.php?

[julianseeger]

fixed

[sebastianbergmann]

I can’t automatically merge this pull request. Can you please rebase/fix? Thanks!

[julianseeger]

I can’t automatically merge this pull request. Can you please rebase/fix? Thanks!

Rebased. Did it help?

[sebastianbergmann]

This is also a bug fix, right? If so, it should go into 2.0.

[julianseeger]

It is, but from my point of view, I'm fine with the next master release here.
The scenario is probably rare so I don't feel the need to fix this in 2.0.