gyp: use keys in calls to sorted (#106)

This replaces uses of the cmp parameter of sorted (which was removed in
Python 3) with either the key parameter, or no parameter where key
seems redundant. This also encodes Unicode strings before hashing them
(which is needed in Python 3).

Fixes: nodejs/node-gyp#2101

pylib/gyp/xcodeproj_file.py

@@ -138,7 +138,9 @@
 """
 
 import gyp.common
+from functools import cmp_to_key
 import hashlib
+from operator import attrgetter
 import posixpath
 import re
 import struct
@@ -423,6 +425,8 @@ def _HashUpdate(hash, data):
       """
 
             hash.update(struct.pack(">i", len(data)))
+            if isinstance(data, str):
+                data = data.encode("utf-8")
             hash.update(data)
 
         if seed_hash is None:
@@ -1483,7 +1487,7 @@ def TakeOverOnlyChild(self, recurse=False):
 
     def SortGroup(self):
         self._properties["children"] = sorted(
-            self._properties["children"], cmp=lambda x, y: x.Compare(y)
+            self._properties["children"], key=cmp_to_key(lambda x, y: x.Compare(y))
         )
 
         # Recurse.
@@ -2891,7 +2895,7 @@ def SortGroups(self):
         # according to their defined order.
         self._properties["mainGroup"]._properties["children"] = sorted(
             self._properties["mainGroup"]._properties["children"],
-            cmp=lambda x, y: x.CompareRootGroup(y),
+            key=cmp_to_key(lambda x, y: x.CompareRootGroup(y)),
         )
 
         # Sort everything else by putting group before files, and going
@@ -2986,9 +2990,7 @@ def AddOrGetProjectReference(self, other_pbxproject):
             # Xcode seems to sort this list case-insensitively
             self._properties["projectReferences"] = sorted(
                 self._properties["projectReferences"],
-                cmp=lambda x, y: cmp(
-                    x["ProjectRef"].Name().lower(), y["ProjectRef"].Name().lower()
-                ),
+                key=lambda x: x["ProjectRef"].Name().lower
             )
         else:
             # The link already exists.  Pull out the relevnt data.
@@ -3120,7 +3122,7 @@ def CompareProducts(x, y, remote_products):
             product_group = ref_dict["ProductGroup"]
             product_group._properties["children"] = sorted(
                 product_group._properties["children"],
-                cmp=lambda x, y, rp=remote_products: CompareProducts(x, y, rp),
+                key=cmp_to_key(lambda x, y, rp=remote_products: CompareProducts(x, y, rp)),
             )
 
 
@@ -3155,7 +3157,7 @@ def Print(self, file=sys.stdout):
         else:
             self._XCPrint(file, 0, "{\n")
         for property, value in sorted(
-            self._properties.items(), cmp=lambda x, y: cmp(x, y)
+            self._properties.items()
         ):
             if property == "objects":
                 self._PrintObjects(file)
@@ -3183,7 +3185,7 @@ def _PrintObjects(self, file):
             self._XCPrint(file, 0, "\n")
             self._XCPrint(file, 0, "/* Begin " + class_name + " section */\n")
             for object in sorted(
-                objects_by_class[class_name], cmp=lambda x, y: cmp(x.id, y.id)
+                objects_by_class[class_name], key=attrgetter("id")
             ):
                 object.Print(file)
             self._XCPrint(file, 0, "/* End " + class_name + " section */\n")