👹 Feed the hobgoblins (delint).

Fix PERF401 errors.

distutils/bcppcompiler.py

@@ -236,8 +236,7 @@ def link(  # noqa: C901
                 temp_dir = os.path.dirname(objects[0])  # preserve tree structure
                 def_file = os.path.join(temp_dir, f'{modname}.def')
                 contents = ['EXPORTS']
-                for sym in export_symbols or []:
-                    contents.append(f'  {sym}=_{sym}')
+                contents.extend(f'  {sym}=_{sym}' for sym in export_symbols)
                 self.execute(write_file, (def_file, contents), f"writing {def_file}")
 
             # Borland C++ has problems with '/' in paths

distutils/ccompiler.py

@@ -1124,10 +1124,10 @@ def show_compilers():
     # commands that use it.
     from distutils.fancy_getopt import FancyGetopt
 
-    compilers = []
-    for compiler in compiler_class.keys():
-        compilers.append(("compiler=" + compiler, None, compiler_class[compiler][2]))
-    compilers.sort()
+    compilers = sorted(
+        ("compiler=" + compiler, None, compiler_class[compiler][2])
+        for compiler in compiler_class.keys()
+    )
     pretty_printer = FancyGetopt(compilers)
     pretty_printer.print_help("List of available compilers:")
 
@@ -1218,8 +1218,7 @@ def gen_preprocess_options(macros, include_dirs):
                 # shell at all costs when we spawn the command!
                 pp_opts.append("-D{}={}".format(*macro))
 
-    for dir in include_dirs:
-        pp_opts.append(f"-I{dir}")
+    pp_opts.extend(f"-I{dir}" for dir in include_dirs)
     return pp_opts
 
 
@@ -1230,10 +1229,7 @@ def gen_lib_options(compiler, library_dirs, runtime_library_dirs, libraries):
     directories.  Returns a list of command-line options suitable for use
     with some compiler (depending on the two format strings passed in).
     """
-    lib_opts = []
-
-    for dir in library_dirs:
-        lib_opts.append(compiler.library_dir_option(dir))
+    lib_opts = [compiler.library_dir_option(dir) for dir in library_dirs]
 
     for dir in runtime_library_dirs:
         lib_opts.extend(always_iterable(compiler.runtime_library_dir_option(dir)))

distutils/command/bdist.py

@@ -15,9 +15,10 @@ def show_formats():
     """Print list of available formats (arguments to "--format" option)."""
     from ..fancy_getopt import FancyGetopt
 
-    formats = []
-    for format in bdist.format_commands:
-        formats.append(("formats=" + format, None, bdist.format_commands[format][1]))
+    formats = [
+        ("formats=" + format, None, bdist.format_commands[format][1])
+        for format in bdist.format_commands
+    ]
     pretty_printer = FancyGetopt(formats)
     pretty_printer.print_help("List of available distribution formats:")
 

distutils/command/build_ext.py

@@ -465,10 +465,7 @@ def get_outputs(self):
         # And build the list of output (built) filenames.  Note that this
         # ignores the 'inplace' flag, and assumes everything goes in the
         # "build" tree.
-        outputs = []
-        for ext in self.extensions:
-            outputs.append(self.get_ext_fullpath(ext.name))
-        return outputs
+        return [self.get_ext_fullpath(ext.name) for ext in self.extensions]
 
     def build_extensions(self):
         # First, sanity-check the 'extensions' list

distutils/command/check.py

@@ -100,10 +100,9 @@ def check_metadata(self):
         """
         metadata = self.distribution.metadata
 
-        missing = []
-        for attr in 'name', 'version':
-            if not getattr(metadata, attr, None):
-                missing.append(attr)
+        missing = [
+            attr for attr in ('name', 'version') if not getattr(metadata, attr, None)
+        ]
 
         if missing:
             self.warn("missing required meta-data: {}".format(', '.join(missing)))

distutils/command/install_lib.py

@@ -161,9 +161,7 @@ def _mutate_outputs(self, has_any, build_cmd, cmd_option, output_dir):
         build_dir = getattr(build_cmd, cmd_option)
 
         prefix_len = len(build_dir) + len(os.sep)
-        outputs = []
-        for file in build_files:
-            outputs.append(os.path.join(output_dir, file[prefix_len:]))
+        outputs = [os.path.join(output_dir, file[prefix_len:]) for file in build_files]
 
         return outputs
 

distutils/command/sdist.py

@@ -24,10 +24,10 @@ def show_formats():
     from ..archive_util import ARCHIVE_FORMATS
     from ..fancy_getopt import FancyGetopt
 
-    formats = []
-    for format in ARCHIVE_FORMATS.keys():
-        formats.append(("formats=" + format, None, ARCHIVE_FORMATS[format][2]))
-    formats.sort()
+    formats = sorted(
+        ("formats=" + format, None, ARCHIVE_FORMATS[format][2])
+        for format in ARCHIVE_FORMATS.keys()
+    )
     FancyGetopt(formats).print_help("List of available source distribution formats:")
 
 

distutils/dist.py

@@ -745,10 +745,7 @@ def print_commands(self):
         for cmd in std_commands:
             is_std.add(cmd)
 
-        extra_commands = []
-        for cmd in self.cmdclass.keys():
-            if cmd not in is_std:
-                extra_commands.append(cmd)
+        extra_commands = [cmd for cmd in self.cmdclass.keys() if cmd not in is_std]
 
         max_length = 0
         for cmd in std_commands + extra_commands:
@@ -776,10 +773,7 @@ def get_command_list(self):
         for cmd in std_commands:
             is_std.add(cmd)
 
-        extra_commands = []
-        for cmd in self.cmdclass.keys():
-            if cmd not in is_std:
-                extra_commands.append(cmd)
+        extra_commands = [cmd for cmd in self.cmdclass.keys() if cmd not in is_std]
 
         rv = []
         for cmd in std_commands + extra_commands:
@@ -1301,7 +1295,4 @@ def fix_help_options(options):
     """Convert a 4-tuple 'help_options' list as found in various command
     classes to the 3-tuple form required by FancyGetopt.
     """
-    new_options = []
-    for help_tuple in options:
-        new_options.append(help_tuple[0:3])
-    return new_options
+    return [opt[0:3] for opt in options]

distutils/msvc9compiler.py

@@ -640,9 +640,7 @@ def link(  # noqa: C901
                 else:
                     ldflags = self.ldflags_shared
 
-            export_opts = []
-            for sym in export_symbols or []:
-                export_opts.append("/EXPORT:" + sym)
+            export_opts = [f"/EXPORT:{sym}" for sym in export_symbols or []]
 
             ld_args = (
                 ldflags + lib_opts + export_opts + objects + ['/OUT:' + output_filename]

distutils/msvccompiler.py

@@ -534,9 +534,7 @@ def link(  # noqa: C901
                 else:
                     ldflags = self.ldflags_shared
 
-            export_opts = []
-            for sym in export_symbols or []:
-                export_opts.append("/EXPORT:" + sym)
+            export_opts = [f"/EXPORT:{sym}" for sym in export_symbols or []]
 
             ld_args = (
                 ldflags + lib_opts + export_opts + objects + ['/OUT:' + output_filename]