Viewing the source of files specified as a relative path doesn't always work. For
instance, a path like:

../../../../some/path/somefile.hpp

won't work for me. It looks like the problem is that it searches the workspace for the whole path rather than just using the file base name. I would suggest just searching for the file base name. If there is more than one result, I'd throw a warning and maybe even include links to each of them. Ideally, the warning should say what went wrong rather than giving all the possible things that might have went wrong. Right now the warnings when viewing source files that aren't found, makes it sound like there are 4 or 5 problems, when normally only one of the problems apply.