[tor-commits] [bridgedb/master] Refactor b.persistent.State with problems found in additional tests.

[isis at torproject.org]

commit cda620bc8a4fac397f07a3bc76fe25a5f8abbcf4
Author: Isis Lovecruft <isis at torproject.org>
Date:   Tue Feb 24 21:04:09 2015 +0000

    Refactor b.persistent.State with problems found in additional tests.
    
     * ADD documentation that `b.persistent.State.load` can raise a
       MissingState exception.
    
     * REMOVE an `else` clause in b.persistent.State.load() that was
       impossible to hit because the `elif` clause right before it should
       always succeed or raise an AttributeError.
    
     * ADD error handling for when pickle.load() is given an opened, but
       empty file, and an EOFError is raised.
    
     * CHANGE b.persistent.State.load() to only raise a MissingState
       exception at the end if there were errors detected during the
       function execution.
    
     * REMOVE unused `err` variable from b.persistent.State.save().
---
 lib/bridgedb/persistent.py |   24 +++++++++++++-----------
 1 file changed, 13 insertions(+), 11 deletions(-)

diff --git a/lib/bridgedb/persistent.py b/lib/bridgedb/persistent.py
index 1c0d3df..ad4398d 100644
--- a/lib/bridgedb/persistent.py
+++ b/lib/bridgedb/persistent.py
@@ -158,6 +158,7 @@ class State(jelly.Jellyable):
     def load(self, statefile=None):
         """Load a previously saved statefile.
 
+        :raises MissingState: If there was any error loading the **statefile**.
         :rtype: :class:`State` or None
         :returns: The state, loaded from :attr:`State.STATEFILE`, or None if
             an error occurred.
@@ -176,8 +177,6 @@ class State(jelly.Jellyable):
                 fh = open(statefile, 'r')
             elif not statefile.closed:
                 fh = statefile
-            else:
-                raise TypeError("Nothing worked.")
         except (IOError, OSError) as error:  # pragma: no cover
             err += "There was an error reading statefile "
             err += "'{0}':\n{1}".format(statefile, error)
@@ -186,14 +185,19 @@ class State(jelly.Jellyable):
             err += "\n\t{0}\nstatefile type = '{1}'".format(
                 error.message, type(statefile))
         else:
-            status = pickle.load(fh)
-            quo = jelly.unjelly(status)
-            if fh is not None:
-                fh.close()
-            if quo:
-                return quo
+            try:
+                status = pickle.load(fh)
+            except EOFError:
+                err += "The statefile %s was empty." % fh.name
+            else:
+                quo = jelly.unjelly(status)
+                if fh is not None:
+                    fh.close()
+                if quo:
+                    return quo
 
-        raise MissingState(err)
+        if err:
+            raise MissingState(err)
 
     def save(self, statefile=None):
         """Save state as a pickled jelly to a file on disk."""
@@ -204,8 +208,6 @@ class State(jelly.Jellyable):
         logging.debug("Saving state to: \t'%s'" % statefile)
 
         fh = None
-        err = ''
-
         try:
             fh = open(statefile, 'w')
         except (IOError, OSError) as error:  # pragma: no cover