Steps to reproduce

1. Have SVN repository with at least one branch and trunk

   $ svn diff --summarize -r 1:8 file:///tmp/repository/project1/
   A       file:///tmp/repository/project1/branches/branch-1/file
   A       file:///tmp/repository/project1/branches/branch-1
   A       file:///tmp/repository/project1/branches
   A       file:///tmp/repository/project1/trunk/file
   A       file:///tmp/repository/project1/trunk
   

   $ svn log -v  file:///tmp/repository/project1/branches/branch-1/file
   ------------------------------------------------------------------------
   r8 | glewandowski | 2016-12-14 12:26:56 +0100 (Wed, 14 Dec 2016) | 1 line
   Changed paths:
      M /project1/branches/branch-1/file
   ------------------------------------------------------------------------
   r7 | glewandowski | 2016-12-14 12:26:32 +0100 (Wed, 14 Dec 2016) | 1 line
   Changed paths:
      M /project1/branches/branch-1/file
   ------------------------------------------------------------------------
   r6 | glewandowski | 2016-12-14 12:26:14 +0100 (Wed, 14 Dec 2016) | 2 lines
   Changed paths:
      A /project1/branches/branch-1 (from /project1/trunk:5)
   
   Created branch-1
   ------------------------------------------------------------------------
   r5 | glewandowski | 2016-12-14 12:26:03 +0100 (Wed, 14 Dec 2016) | 1 line
   Changed paths:
      M /project1/trunk/file
   ------------------------------------------------------------------------
   r4 | glewandowski | 2016-12-14 12:25:50 +0100 (Wed, 14 Dec 2016) | 1 line
   Changed paths:
      M /project1/trunk/file
   ------------------------------------------------------------------------
   r3 | glewandowski | 2016-12-14 12:25:35 +0100 (Wed, 14 Dec 2016) | 1 line
   Changed paths:
      A /project1/trunk/file
   

2. Create review
3. Add content via Explore repositories
4. Change Add to Review as select to Diffs to ...
5. Put 5 (or any commit number which was made on trunk)
   

Expected behaviour

Revisions project1/branches/branch-1/file@8 and project1/trunk/file@5 are added to review and diff generates properly between them or meaningful information is presented to a user.

Actual behaviour

FishEye ignores logical paths for a file and fails with NPE.

Potentially the same problem exists for Perforce repositories

There's a code which handles such situation when a revision is on a tag and completely disregards the situation like here when it's on a branch.
Code Snippet from com.cenqua.fisheye.svn.db.SvnRevInfoDAO#getRevId

public int getRevId(Path path, long changesetId) throws DbException {
        int revid = getPureRevId(path, changesetId);
        if (revid == -1 && pathMatcher.isTag(path)) {
            String tag = pathMatcher.getTag(path);
            Path logicalPath = getLogicalPath(path);
            revid = getTaggedPathRevid(logicalPath, tag, changesetId);
        }
        return revid;
    }

Workaround

If user wants to generate diff to a branch point, simply se Diff to branch point