Simplify dict iterations from Python 2 to 3 migration

AutoDuck/Dump2HHC.py

@@ -231,9 +231,7 @@ def _urlescape(name):
 
 
 def _genCategoryHTMLFromDict(dict, output):
-    keys = list(dict.keys())
-    keys.sort()
-    for key in keys:
+    for key in sorted(dict):
         topic = dict[key]
         output.write(f'<LI><A HREF="{topic.context}">{topic.name}</A>\n')
 
@@ -285,9 +283,7 @@ def genCategoryHTML(output_dir, cats):
 
 def _genItemsFromDict(dict, cat, output, target, do_children=1):
     CHM = "mk:@MSITStore:%s.chm::/" % target
-    keys = list(dict.keys())
-    keys.sort()
-    for k in keys:
+    for k in sorted(dict):
         context = dict[k].context
         name = dict[k].name
         output.write(

AutoDuck/InsertExternalOverviews.py

@@ -26,12 +26,8 @@ def genHTML(doc):
     s = ""
     for cat in doc:
         s += f"<H3>{cat.label}</H3>\n"
-        dict = {}
-        for item in cat.overviewItems.items:
-            dict[item.name] = item.href
-        keys = list(dict.keys())
-        keys.sort()
-        for k in keys:
+        dict = {item.name: item.href for item in cat.overviewItems.items}
+        for k in sorted(dict):
             s += f'<LI><A HREF="html/{dict[k]}">{k}</A>\n'
     return s
 

AutoDuck/py2d.py

@@ -100,7 +100,7 @@ def build_module(fp, mod_name):
     functions = []
     classes = []
     constants = []
-    for name, ob in list(mod.__dict__.items()):
+    for name, ob in mod.__dict__.items():
         if name.startswith("_"):
             continue
         if hasattr(ob, "__module__") and ob.__module__ != mod_name:
@@ -139,7 +139,7 @@ def build_module(fp, mod_name):
         func_infos = []
         # We need to iter the keys then to a getattr() so the funky descriptor
         # things work.
-        for n in list(ob.ob.__dict__.keys()):
+        for n in ob.ob.__dict__:
             o = getattr(ob.ob, n)
             if isinstance(o, (types.FunctionType, types.MethodType)):
                 info = BuildInfo(n, o)

CHANGES.txt

@@ -14,6 +14,7 @@ https://mhammond.github.io/pywin32_installers.html.
 Coming in build 309, as yet unreleased
 --------------------------------------
 
+* Improved handling of dict iterations (removes Python 2 support code, small general speed improvement) (#2332, @Avasam)
 * Fixed "Open GL Demo" (`Pythonwin/pywin/Demos/openGLDemo.py`) and restore "Font" demo in `Pythonwin/pywin/Demos/guidemo.py` (#2345, @Avasam)
 
 Build 308, released 2024-10-12

Pythonwin/pywin/Demos/app/customprint.py

@@ -45,9 +45,7 @@ def OnDraw(self, dc):
         oldPen = None
         x, y = self.size
         delta = 2
-        colors = list(self.colors.keys())
-        colors.sort()
-        colors *= 2
+        colors = sorted(self.colors) * 2
         for color in colors:
             if oldPen is None:
                 oldPen = dc.SelectObject(self.pens[color])

Pythonwin/pywin/debugger/configui.py

@@ -19,7 +19,7 @@ def OnInitDialog(self):
     def OnOK(self):
         self.UpdateData()
         dirty = 0
-        for key, val in list(self.items()):
+        for key, val in self.items():
             if key in self.options:
                 if self.options[key] != val:
                     self.options[key] = val

Pythonwin/pywin/debugger/debugger.py

@@ -389,7 +389,7 @@ def DeleteSelected(self):
             item_id = self.GetItem(num)[6]
             from bdb import Breakpoint
 
-            for bplist in list(Breakpoint.bplist.values()):
+            for bplist in Breakpoint.bplist.values():
                 for bp in bplist:
                     if id(bp) == item_id:
                         self.debugger.clear_break(bp.file, bp.line)

Pythonwin/pywin/framework/dbgcommands.py

@@ -37,7 +37,7 @@ def HookCommands(self):
             if not methUpdate is None:
                 frame.HookCommandUpdate(methUpdate, id)
 
-        for id in list(IdToBarNames.keys()):
+        for id in IdToBarNames:
             frame.HookCommand(self.OnDebuggerBar, id)
             frame.HookCommandUpdate(self.OnUpdateDebuggerBar, id)
 

Pythonwin/pywin/framework/mdi_pychecker.py

@@ -112,9 +112,7 @@ def __init__(self, str, recurse=0):
                                     sd = sd.lower()
                                     if sd not in dirs:
                                         dirs[sd] = None
-        self.dirs = []
-        for d in dirs.keys():
-            self.dirs.append(d)
+        self.dirs = list(dirs)
 
     def __getitem__(self, key):
         return self.dirs[key]

Pythonwin/pywin/framework/scriptutils.py

@@ -440,7 +440,7 @@ def ImportFile():
     # note that some packages (*cough* email *cough*) use "lazy importers"
     # meaning sys.modules can change as a side-effect of looking at
     # module.__file__ - so we must take a copy (ie, list(items()))
-    for key, mod in list(sys.modules.items()):
+    for key, mod in sys.modules.items():
         if getattr(mod, "__file__", None):
             fname = mod.__file__
             base, ext = os.path.splitext(fname)

Pythonwin/pywin/framework/sgrepmdi.py

@@ -94,9 +94,7 @@ def __init__(self, str, recurse=0):
                                     sd = sd.lower()
                                     if sd not in dirs:
                                         dirs[sd] = None
-        self.dirs = []
-        for d in list(dirs.keys()):
-            self.dirs.append(d)
+        self.dirs = list(dirs)
 
     def __getitem__(self, key):
         return self.dirs[key]

Pythonwin/pywin/mfc/dialog.py

@@ -83,13 +83,13 @@ def __setitem__(self, key, item):
         self._obj_.data[key] = item  # self.UpdateData(0)
 
     def keys(self):
-        return list(self.data.keys())
+        return self.data.keys()
 
     def items(self):
-        return list(self.data.items())
+        return self.data.items()
 
     def values(self):
-        return list(self.data.values())
+        return self.data.values()
 
     def __contains__(self, key):
         return key in self.data

Pythonwin/pywin/scintilla/bindings.py

@@ -56,7 +56,7 @@ def prepare_configure(self):
         self.keymap = {}
 
     def complete_configure(self):
-        for id in command_to_events.keys():
+        for id in command_to_events:
             self.parent_view.HookCommand(self._OnCommand, id)
 
     def close(self):

Pythonwin/pywin/scintilla/config.py

@@ -198,7 +198,7 @@ def configure(self, editor, subsections=None):
                 ns = None
             if ns:
                 num = 0
-                for name, func in list(ns.items()):
+                for name, func in ns.items():
                     if isinstance(func, types.FunctionType) and name[:1] != "_":
                         bindings.bind(name, func)
                         num += 1
@@ -230,10 +230,8 @@ def get_key_binding(self, event, subsections=None):
         for subsection in subsections:
             map = self.key_to_events.get(subsection)
             if map is None:  # Build it
-                map = {}
                 keymap = subsection_keymap.get(subsection, {})
-                for key_info, map_event in list(keymap.items()):
-                    map[map_event] = key_info
+                map = {map_event: key_info for key_info, map_event in keymap.items()}
                 self.key_to_events[subsection] = map
 
             info = map.get(event)

Pythonwin/pywin/scintilla/configui.py

@@ -88,8 +88,7 @@ def OnInitDialog(self):
             self.butIsDefaultBackground = self.GetDlgItem(win32ui.IDC_CHECK2)
             self.listbox = self.GetDlgItem(win32ui.IDC_LIST1)
             self.HookCommand(self.OnListCommand, win32ui.IDC_LIST1)
-            names = list(self.styles.keys())
-            names.sort()
+            names = sorted(self.styles)
             for name in names:
                 if self.styles[name].aliased is None:
                     self.listbox.AddString(name)

Pythonwin/pywin/scintilla/formatter.py

@@ -185,7 +185,7 @@ def ApplyFormattingStyles(self, bReload=1):
         defaultStyle = Style("default", baseFormat)
         defaultStyle.stylenum = scintillacon.STYLE_DEFAULT
         self._ReformatStyle(defaultStyle)
-        for style in list(self.styles.values()):
+        for style in self.styles.values():
             if style.aliased is None:
                 style.NormalizeAgainstDefault(baseFormat)
             self._ReformatStyle(style)
@@ -202,7 +202,7 @@ def LoadPreferences(self):
         )
         self.bUseFixed = int(self.LoadPreference("Use Fixed", 1))
 
-        for style in list(self.styles.values()):
+        for style in self.styles.values():
             new = self.LoadPreference(style.name, str(style.format))
             try:
                 style.format = eval(new)
@@ -222,7 +222,7 @@ def SavePreferences(self):
         self.SavePreference("Base Format Fixed", str(self.baseFormatFixed))
         self.SavePreference("Base Format Proportional", str(self.baseFormatProp))
         self.SavePreference("Use Fixed", self.bUseFixed)
-        for style in list(self.styles.values()):
+        for style in self.styles.values():
             if style.aliased is None:
                 self.SavePreference(style.name, str(style.format))
                 bg_name = style.name + " background"

Pythonwin/pywin/scintilla/view.py

@@ -517,10 +517,14 @@ def list2dict(l):
                     )
                 )
 
-        # ensure all keys are strings.
-        items = [str(k) for k in items_dict.keys()]
-        # All names that start with "_" go!
-        items = [k for k in items if not k.startswith("_")]
+        items = [
+            k
+            for k in
+            # ensure all keys are strings.
+            map(str, items_dict)
+            # All names that start with "_" go!
+            if not k.startswith("_")
+        ]
 
         if not items:
             # Heuristics a-la AutoExpand
@@ -550,9 +554,7 @@ def list2dict(l):
             if curclass and left == "self":
                 self._UpdateWithClassMethods(unique, curclass)
 
-            items = [
-                word for word in unique.keys() if word[:2] != "__" or word[-2:] != "__"
-            ]
+            items = [word for word in unique if word[:2] != "__" or word[-2:] != "__"]
             # Ignore the word currently to the right of the dot - probably a red-herring.
             try:
                 items.remove(right[1:])

Pythonwin/pywin/tools/browser.py

@@ -110,7 +110,7 @@ def CalculateIsExpandable(self):
         if hasattr(self.myobject, "__doc__"):
             return 1
         try:
-            for key in self.myobject.__dict__.keys():
+            for key in self.myobject.__dict__:
                 if key not in special_names:
                     return 1
         except (AttributeError, TypeError):
@@ -288,12 +288,7 @@ def IsExpandable(self):
             return len(self.myobject) > 0
 
     def GetSubList(self):
-        ret = []
-        keys = list(self.myobject.keys())
-        keys.sort()
-        for key in keys:
-            ob = self.myobject[key]
-            ret.append(MakeHLI(ob, str(key)))
+        ret = [MakeHLI(self.myobject[key], str(key)) for key in sorted(self.myobject)]
         self.InsertDocString(ret)
         return ret
 

com/win32com/client/__init__.py

@@ -7,6 +7,7 @@
 # with dynamic.Dispatch behaviour, where dynamic objects are always used.
 
 import sys
+from itertools import chain
 
 import pythoncom
 import pywintypes
@@ -510,17 +511,18 @@ def __init__(self, oobj=None):
         self.__dict__["_oleobj_"] = oobj  # so we don't call __setattr__
 
     def __dir__(self):
-        lst = (
-            list(self.__dict__.keys())
-            + dir(self.__class__)
-            + list(self._prop_map_get_.keys())
-            + list(self._prop_map_put_.keys())
+        attributes = chain(
+            self.__dict__,
+            dir(self.__class__),
+            self._prop_map_get_,
+            self._prop_map_put_,
         )
+
         try:
-            lst += [p.Name for p in self.Properties_]
+            attributes = chain(attributes, [p.Name for p in self.Properties_])
         except AttributeError:
             pass
-        return list(set(lst))
+        return list(set(attributes))
 
     # Provide a prettier name than the CLSID
     def __repr__(self):

com/win32com/client/build.py

@@ -18,6 +18,7 @@
 
 import datetime
 import string
+from itertools import chain
 from keyword import iskeyword
 
 import pythoncom
@@ -493,18 +494,20 @@ def Build(self, typeinfo, attr, bForUser=1):
         DispatchItem.Build(self, typeinfo, attr, bForUser)
         assert typeinfo is not None, "Can't build vtables without type info!"
 
-        meth_list = (
-            list(self.mapFuncs.values())
-            + list(self.propMapGet.values())
-            + list(self.propMapPut.values())
+        meth_list = sorted(
+            chain(
+                self.mapFuncs.values(),
+                self.propMapGet.values(),
+                self.propMapPut.values(),
+            ),
+            key=lambda m: m.desc[7],
         )
-        meth_list.sort(key=lambda m: m.desc[7])
 
         # Now turn this list into the run-time representation
         # (ready for immediate use or writing to gencache)
-        self.vtableFuncs = []
-        for entry in meth_list:
-            self.vtableFuncs.append((entry.names, entry.dispid, entry.desc))
+        self.vtableFuncs = [
+            (entry.names, entry.dispid, entry.desc) for entry in meth_list
+        ]
 
 
 # A Lazy dispatch item - builds an item on request using info from

com/win32com/client/dynamic.py

@@ -17,6 +17,7 @@
 """
 
 import traceback
+from itertools import chain
 from types import MethodType
 
 import pythoncom  # Needed as code we eval() references it.
@@ -233,19 +234,19 @@ def __str__(self):
             return self.__repr__()
 
     def __dir__(self):
-        lst = list(self.__dict__.keys()) + dir(self.__class__) + self._dir_ole_()
+        attributes = chain(self.__dict__, dir(self.__class__), self._dir_ole_())
         try:
-            lst += [p.Name for p in self.Properties_]
+            attributes = chain(attributes, [p.Name for p in self.Properties_])
         except AttributeError:
             pass
-        return list(set(lst))
+        return list(set(attributes))
 
     def _dir_ole_(self):
         items_dict = {}
         for iTI in range(0, self._oleobj_.GetTypeInfoCount()):
             typeInfo = self._oleobj_.GetTypeInfo(iTI)
             self._UpdateWithITypeInfo_(items_dict, typeInfo)
-        return list(items_dict.keys())
+        return list(items_dict)
 
     def _UpdateWithITypeInfo_(self, items_dict, typeInfo):
         typeInfos = [typeInfo]
@@ -455,7 +456,7 @@ def _print_details_(self):
         print("AxDispatch container", self._username_)
         try:
             print("Methods:")
-            for method in self._olerepr_.mapFuncs.keys():
+            for method in self._olerepr_.mapFuncs:
                 print("\t", method)
             print("Props:")
             for prop, entry in self._olerepr_.propMap.items():