Revert "Don't clobber sys.path[0]. #715"

This reverts commit e82d24d.

CHANGES.rst

@@ -23,17 +23,13 @@ Unreleased
 - Coverage will create directories as needed for the data file if they don't
   exist, closing `issue 721`_.
 
-- Coverage commands no longer clobber the first entry in sys.path, fixing
-  `issue 715`_.
-
 - Improvements to context support:
 
   - The "no such table: meta" error is fixed.: `issue 716`_.
 
   - Combining data files now goes much faster.
 
 .. _issue 695: https://github.com/nedbat/coveragepy/issues/695
-.. _issue 715: https://github.com/nedbat/coveragepy/issues/715
 .. _issue 716: https://github.com/nedbat/coveragepy/issues/716
 .. _issue 721: https://github.com/nedbat/coveragepy/issues/721
 

coverage/cmdline.py

@@ -466,6 +466,10 @@ def command_line(self, argv):
         if self.do_help(options, args, parser):
             return OK
 
+        # We need to be able to import from the current directory, because
+        # plugins may try to, for example, to read Django settings.
+        sys.path[0] = ''
+
         # Listify the list options.
         source = unshell_list(options.source)
         omit = unshell_list(options.omit)