lastline can be referenced before it is assigned to

[terrycojones]

In __init__.py there's this code:

                    for i, line in enumerate(fastafile):
                        line_blen = len(line)
                        line_clen = len(line.rstrip('\n\r'))
                        lastline = i

lastline is not initialized before the for loop. So if fastafile is empty, lastline is not set. But it is then used on line 452. This results in

Traceback (most recent call last):
  File "/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/unittest/case.py", line 331, in run
    testMethod()
  File "/Users/terry/dark-matter/dark-matter/test/test_fasta.py", line 459, in testEmpty
    reads = FastaFaiReads('filename.fasta')
  File "/Users/terry/dark-matter/dark-matter/dark/fasta.py", line 146, in __init__
    self._fasta = Fasta(filename)
  File "build/bdist.macosx-10.10-intel/egg/pyfaidx/__init__.py", line 724, in __init__

  File "build/bdist.macosx-10.10-intel/egg/pyfaidx/__init__.py", line 351, in __init__

  File "build/bdist.macosx-10.10-intel/egg/pyfaidx/__init__.py", line 452, in build_index

exceptions.UnboundLocalError: local variable 'lastline' referenced before assignment