share: allow trailing newline on .hg/sharedpath.

This is extremely handy for those occasional circumstances where you
need to edit .hg/sharedpath manually, since modern Unix text editors
make it surprisingly difficult to create a text file with no trailing
newline.

mercurial/localrepo.py

@@ -79,7 +79,7 b' class localrepository(repo.repository):'
 
         self.sharedpath = self.path
         try:
-            s = os.path.realpath(self.opener.read("sharedpath"))
+            s = os.path.realpath(self.opener.read("sharedpath").rstrip('\n'))
             if not os.path.exists(s):
                 raise error.RepoError(
                     _('.hg/sharedpath points to nonexistent directory %s') % s)

tests/test-share.t

@@ -28,6 +28,15 b' Some sed versions appends newline, some '
   $ cat .hg/sharedpath; echo
   $TESTTMP/repo1/.hg
 
+trailing newline on .hg/sharedpath is ok
+  $ hg tip -q
+  0:d3873e73d99e
+  $ echo '' >> .hg/sharedpath
+  $ cat .hg/sharedpath
+  $TESTTMP/repo1/.hg
+  $ hg tip -q
+  0:d3873e73d99e
+
 commit in shared clone
 
   $ echo a >> a