Use set instead of True-only dict for non-public names (#4381)

pkg_resources/__init__.py

@@ -724,15 +724,15 @@ def __iter__(self) -> Iterator[Distribution]:
         The yield order is the order in which the items' path entries were
         added to the working set.
         """
-        seen = {}
+        seen = set()
         for item in self.entries:
             if item not in self.entry_keys:
                 # workaround a cache issue
                 continue
 
             for key in self.entry_keys[item]:
                 if key not in seen:
-                    seen[key] = True
+                    seen.add(key)
                     yield self.by_key[key]
 
     def add(
@@ -808,7 +808,7 @@ def resolve(
         # set up the stack
         requirements = list(requirements)[::-1]
         # set of processed requirements
-        processed = {}
+        processed = set()
         # key -> dist
         best = {}
         to_activate = []
@@ -842,7 +842,7 @@ def resolve(
                 required_by[new_requirement].add(req.project_name)
                 req_extras[new_requirement] = req.extras
 
-            processed[req] = True
+            processed.add(req)
 
         # return list of distros to activate
         return to_activate
@@ -1313,7 +1313,7 @@ def get_cache_path(self, archive_name: str, names: Iterable[StrPath] = ()):
 
         self._warn_unsafe_extraction_path(extract_path)
 
-        self.cached_files[target_path] = 1
+        self.cached_files[target_path] = True
         return target_path
 
     @staticmethod

setuptools/command/easy_install.py

@@ -1047,7 +1047,7 @@ def exe_to_egg(self, dist_filename, egg_tmp):  # noqa: C901
         prefixes = get_exe_prefixes(dist_filename)
         to_compile = []
         native_libs = []
-        top_level = {}
+        top_level = set()
 
         def process(src, dst):
             s = src.lower()
@@ -1059,10 +1059,10 @@ def process(src, dst):
                     dl = dst.lower()
                     if dl.endswith('.pyd') or dl.endswith('.dll'):
                         parts[-1] = bdist_egg.strip_module(parts[-1])
-                        top_level[os.path.splitext(parts[0])[0]] = True
+                        top_level.add([os.path.splitext(parts[0])[0]])
                         native_libs.append(src)
                     elif dl.endswith('.py') and old != 'SCRIPTS/':
-                        top_level[os.path.splitext(parts[0])[0]] = True
+                        top_level.add([os.path.splitext(parts[0])[0]])
                         to_compile.append(dst)
                     return dst
             if not src.endswith('.pth'):
@@ -1484,14 +1484,14 @@ def get_site_dirs():
 def expand_paths(inputs):  # noqa: C901  # is too complex (11)  # FIXME
     """Yield sys.path directories that might contain "old-style" packages"""
 
-    seen = {}
+    seen = set()
 
     for dirname in inputs:
         dirname = normalize_path(dirname)
         if dirname in seen:
             continue
 
-        seen[dirname] = True
+        seen.add(dirname)
         if not os.path.isdir(dirname):
             continue
 
@@ -1520,7 +1520,7 @@ def expand_paths(inputs):  # noqa: C901  # is too complex (11)  # FIXME
                 if line in seen:
                     continue
 
-                seen[line] = True
+                seen.add(line)
                 if not os.path.isdir(line):
                     continue
 
@@ -1622,7 +1622,7 @@ def __init__(self, filename, sitedirs=()):
     def _load_raw(self):
         paths = []
         dirty = saw_import = False
-        seen = dict.fromkeys(self.sitedirs)
+        seen = set(self.sitedirs)
         f = open(self.filename, 'rt', encoding=py39.LOCALE_ENCODING)
         # ^-- Requires encoding="locale" instead of "utf-8" (python/cpython#77102).
         for line in f:
@@ -1643,7 +1643,7 @@ def _load_raw(self):
                 dirty = True
                 paths.pop()
                 continue
-            seen[normalized_path] = True
+            seen.add(normalized_path)
         f.close()
         # remove any trailing empty/blank line
         while paths and not paths[-1].strip():

setuptools/package_index.py

@@ -627,7 +627,7 @@ def fetch_distribution(  # noqa: C901  # is too complex (14)  # FIXME
         """
         # process a Requirement
         self.info("Searching for %s", requirement)
-        skipped = {}
+        skipped = set()
         dist = None
 
         def find(req, env=None):
@@ -642,7 +642,7 @@ def find(req, env=None):
                             "Skipping development or system egg: %s",
                             dist,
                         )
-                        skipped[dist] = True
+                        skipped.add(dist)
                     continue
 
                 test = dist in req and (dist.precedence <= SOURCE_DIST or not source)

setuptools/tests/test_dist_info.py

@@ -122,7 +122,7 @@ def test_output_dir(self, tmp_path, keep_egg_info):
         run_command("dist_info", "--output-dir", out, *opts, cwd=tmp_path)
         assert len(list(out.glob("*.dist-info"))) == 1
         assert len(list(tmp_path.glob("*.dist-info"))) == 0
-        expected_egg_info = 1 if keep_egg_info else 0
+        expected_egg_info = int(keep_egg_info)
         assert len(list(out.glob("*.egg-info"))) == expected_egg_info
         assert len(list(tmp_path.glob("*.egg-info"))) == 0
         assert len(list(out.glob("*.__bkp__"))) == 0