PY3: use fast cPickle module for Python 2

Move all pickle imports to module level, no benefit to keep them local.
pavoljuhas · Sep 25, 2019 · Sep 25, 2019 · Sep 25, 2019 · Sep 26, 2019 · Sep 26, 2019
commit 15bbfa67b6b9214b227b4732d40475e72ab739e9
diff --git a/src/diffpy/pdfgui/control/calculation.py b/src/diffpy/pdfgui/control/calculation.py
@@ -18,7 +18,7 @@
 
 import copy
 import math
-import types
+import six.moves.cPickle as pickle
 
 from diffpy.pdfgui.control.controlerrors import ControlConfigError
 from diffpy.pdfgui.control.controlerrors import ControlKeyError
@@ -248,8 +248,7 @@ def load(self, z, subpath):
 
         returns a tree of internal hierachy
         """
-        import cPickle
-        config = cPickle.loads(z.read(subpath + 'config'))
+        config = pickle.loads(z.read(subpath + 'config'))
         self.rmin = config['rmin']
         self.rstep = config['rstep']
         self.rmax = config['rmax']

diff --git a/src/diffpy/pdfgui/control/fitdataset.py b/src/diffpy/pdfgui/control/fitdataset.py
@@ -17,6 +17,7 @@
 """
 
 import copy
+import six.moves.cPickle as pickle
 import numpy
 
 from diffpy.pdfgui.control.pdfdataset import PDFDataSet
@@ -455,12 +456,11 @@ def load(self, z, subpath):
         self.clear()
         subs = subpath.split('/')
         rootDict = z.fileTree[subs[0]][subs[1]][subs[2]][subs[3]]
-        import cPickle
         # raw data
         self.readObsStr(z.read(subpath+'obs'))
 
         # data from calculation
-        content = cPickle.loads(z.read(subpath+'calc'))
+        content = pickle.loads(z.read(subpath+'calc'))
         for item in FitDataSet.persistentItems:
             # skip items which are not in the project file
             if item not in content: continue

diff --git a/src/diffpy/pdfgui/control/fitting.py b/src/diffpy/pdfgui/control/fitting.py
@@ -15,6 +15,7 @@
 
 from __future__ import print_function
 
+import six.moves.cPickle as pickle
 import threading
 import time
 
@@ -193,15 +194,14 @@ def load(self, z, subpath):
         subs = subpath.split('/')
         rootDict = z.fileTree[subs[0]][subs[1]]
 
-        import cPickle
         if rootDict.has_key('parameters'):
             from diffpy.pdfgui.control.pdfguicontrol import CtrlUnpickler
             self.parameters = CtrlUnpickler.loads(z.read(subpath+'parameters'))
         if rootDict.has_key('steps'):
             self.itemIndex, self.dataNameDict, self.snapshots = \
-                    cPickle.loads(z.read(subpath+'steps'))
+                    pickle.loads(z.read(subpath+'steps'))
         if rootDict.has_key('result'):
-            self.rw, self.res = cPickle.loads(z.read(subpath+'result'))
+            self.rw, self.res = pickle.loads(z.read(subpath+'result'))
 
         return Organizer.load(self, z, subpath)
 

diff --git a/src/diffpy/pdfgui/control/pdfguicontrol.py b/src/diffpy/pdfgui/control/pdfguicontrol.py
@@ -19,6 +19,7 @@
 import os
 import threading
 import time
+import six.moves.cPickle as pickle
 
 from diffpy.pdfgui.control.pdflist import PDFList
 from diffpy.pdfgui.control.fitting import Fitting
@@ -359,7 +360,6 @@ def _nameParser(namelist):
         self.projfile = projfile
         organizations = []
         import zipfile
-        from cPickle import PickleError
         from diffpy.pdfgui.utils import quote_plain
 
         # IOError can be raised when reading invalid zipfile
@@ -409,7 +409,7 @@ def _nameParser(namelist):
                 organizations.append(org)
                 self.add(fit)
 
-        except (IOError, zipfile.error, PickleError):
+        except (IOError, zipfile.error, pickle.PickleError):
             raise ControlFileError(emsg_invalid_file)
 
         # close input file if opened
@@ -437,7 +437,6 @@ def save(self, projfile=None):
 
         import zipfile
         import shutil
-        from cPickle import PickleError
         import tempfile
         from diffpy.pdfgui.utils import quote_plain
 
@@ -463,7 +462,7 @@ def save(self, projfile=None):
             z.close()
             shutil.copyfile(tmpfilename, self.projfile)
 
-        except (IOError, PickleError):
+        except (IOError, pickle.PickleError):
             emsg = "Error when writing to %s" % self.projfile
             raise ControlFileError(emsg)
 
@@ -568,9 +567,8 @@ class CtrlUnpickler:
     pickle.
     '''
     def loads(s):
-        import cPickle
         try:
-            return cPickle.loads(s)
+            return pickle.loads(s)
         except ImportError,err:
             missedModule = str(err).split(' ')[-1]
             if missedModule.find('pdfgui.control') == -1:
@@ -580,7 +578,7 @@ def loads(s):
             except ImportError:
                 from StringIO import StringIO
             f = StringIO(s)
-            unpickler = cPickle.Unpickler(f)
+            unpickler = pickle.Unpickler(f)
             unpickler.find_global = _find_global
             return unpickler.load()
     loads = _StaticMethod(loads)

diff --git a/src/diffpy/pdfgui/gui/fittree.py b/src/diffpy/pdfgui/gui/fittree.py
@@ -24,7 +24,7 @@
 
 import wx
 import re
-import cPickle
+import six.moves.cPickle as pickle
 
 from diffpy.pdfgui.gui.pdfguiglobals import iconpath
 from diffpy.pdfgui.control.fitting import Fitting
@@ -556,7 +556,7 @@ def CopyBranch(self, startnode):
         if isinstance(cdata, Fitting):
             cdata = cdata.stripped()
         cdata.type = nodetype
-        cdatastring = cPickle.dumps(cdata)
+        cdatastring = pickle.dumps(cdata)
         cdatastring = "pdfgui_cliboard=" + cdatastring
         textdata = wx.TextDataObject(cdatastring)
         if not wx.TheClipboard.IsOpened():
@@ -589,14 +589,9 @@ def GetClipboard(self):
         if cdatastring[:16] == "pdfgui_cliboard=":
             cdatastring = cdatastring[16:]
             try:
-                cdata = cPickle.loads(str(cdatastring))
+                cdata = pickle.loads(str(cdatastring))
             except:
                 pass
-
-        #try:
-        #    cdata = cPickle.loads(str(cdatastring))
-        #except (cPickle.UnpicklingError, UnicodeEncodeError, EOFError):
-        #    cdata = None
         return cdata
 
     def PasteBranch(self, entrypoint = None):

diff --git a/src/diffpy/pdfgui/utils.py b/src/diffpy/pdfgui/utils.py
@@ -15,11 +15,12 @@
 
 """Small shared routines:
     numericStringSort   -- sort list of strings according to numeric value
-    safeCPickleDumps    -- same as cPickleDumps, but safe for NaN and Inf
+    safeCPickleDumps    -- same as pickle.dumps, but safe for NaN and Inf
 """
 
 
 from ConfigParser import RawConfigParser
+import six.moves.cPickle as pickle
 
 
 def numericStringSort(lst):
@@ -41,20 +42,19 @@ def numericStringSort(lst):
     return
 
 def safeCPickleDumps(obj):
-    """Get cPickle representation of an object possibly containing NaN or Inf.
-    By default it uses cPickle.HIGHEST_PROTOCOL, but falls back to ASCII
+    """Get pickle representation of an object possibly containing NaN or Inf.
+    By default it uses pickle.HIGHEST_PROTOCOL, but falls back to ASCII
     protocol 0 if there is SystemError frexp() exception.
 
     obj -- object to be pickled
 
-    Return cPickle string.
+    Return pickle string.
     """
-    import cPickle
     ascii_protocol = 0
     try:
-        s = cPickle.dumps(obj, cPickle.HIGHEST_PROTOCOL)
+        s = pickle.dumps(obj, pickle.HIGHEST_PROTOCOL)
     except SystemError:
-        s = cPickle.dumps(obj, ascii_protocol)
+        s = pickle.dumps(obj, ascii_protocol)
     return s