Add type hints to Tools/patchcheck/patchcheck.py

Tools/patchcheck/patchcheck.py

@@ -1,32 +1,35 @@
 #!/usr/bin/env python3
 """Check proposed changes for common issues."""
+
 import sys
 import os.path
 import subprocess
 import sysconfig
+from typing import Callable, Optional
 
 
-def get_python_source_dir():
-    src_dir = sysconfig.get_config_var('abs_srcdir')
+def get_python_source_dir() -> str:
+    src_dir = sysconfig.get_config_var("abs_srcdir")
     if not src_dir:
-        src_dir = sysconfig.get_config_var('srcdir')
+        src_dir = sysconfig.get_config_var("srcdir")
     return os.path.abspath(src_dir)
 
 
 SRCDIR = get_python_source_dir()
 
 
-def n_files_str(count):
+def n_files_str(count: int) -> str:
     """Return 'N file(s)' with the proper plurality on 'file'."""
     s = "s" if count != 1 else ""
     return f"{count} file{s}"
 
 
-def status(message, modal=False, info=None):
+def status(message: str, modal: bool = False, info: Optional[Callable] = None):
     """Decorator to output status info to stdout."""
+
     def decorated_fxn(fxn):
         def call_fxn(*args, **kwargs):
-            sys.stdout.write(message + ' ... ')
+            sys.stdout.write(message + " ... ")
             sys.stdout.flush()
             result = fxn(*args, **kwargs)
             if not modal and not info:
@@ -40,19 +43,18 @@ def call_fxn(*args, **kwargs):
     return decorated_fxn
 
 
-def get_git_branch():
+def get_git_branch() -> Optional[str]:
     """Get the symbolic name for the current git branch"""
     cmd = "git rev-parse --abbrev-ref HEAD".split()
     try:
-        return subprocess.check_output(cmd,
-                                       stderr=subprocess.DEVNULL,
-                                       cwd=SRCDIR,
-                                       encoding='UTF-8')
+        return subprocess.check_output(
+            cmd, stderr=subprocess.DEVNULL, cwd=SRCDIR, encoding="UTF-8"
+        )
     except subprocess.CalledProcessError:
         return None
 
 
-def get_git_upstream_remote():
+def get_git_upstream_remote() -> str:
     """
     Get the remote name to use for upstream branches
 
@@ -63,14 +65,12 @@ def get_git_upstream_remote():
     """
     cmd = "git remote -v".split()
     output = subprocess.check_output(
-        cmd,
-        stderr=subprocess.DEVNULL,
-        cwd=SRCDIR,
-        encoding="UTF-8"
+        cmd, stderr=subprocess.DEVNULL, cwd=SRCDIR, encoding="UTF-8"
     )
     # Filter to desired remotes, accounting for potential uppercasing
     filtered_remotes = {
-        remote.split("\t")[0].lower() for remote in output.split('\n')
+        remote.split("\t")[0].lower()
+        for remote in output.split("\n")
         if "python/cpython" in remote.lower() and remote.endswith("(fetch)")
     }
     if len(filtered_remotes) == 1:
@@ -80,7 +80,7 @@ def get_git_upstream_remote():
         if remote_name in filtered_remotes:
             return remote_name
     remotes_found = "\n".join(
-        {remote for remote in output.split('\n') if remote.endswith("(fetch)")}
+        {remote for remote in output.split("\n") if remote.endswith("(fetch)")}
     )
     raise ValueError(
         f"Patchcheck was unable to find an unambiguous upstream remote, "
@@ -89,23 +89,25 @@ def get_git_upstream_remote():
         f"https://devguide.python.org/getting-started/"
         f"git-boot-camp/#cloning-a-forked-cpython-repository "
         f"\nRemotes found: \n{remotes_found}"
-        )
+    )
 
 
-def get_git_remote_default_branch(remote_name):
+def get_git_remote_default_branch(remote_name: str) -> Optional[str]:
     """Get the name of the default branch for the given remote
 
     It is typically called 'main', but may differ
     """
     cmd = f"git remote show {remote_name}".split()
     env = os.environ.copy()
-    env['LANG'] = 'C'
+    env["LANG"] = "C"
     try:
-        remote_info = subprocess.check_output(cmd,
-                                              stderr=subprocess.DEVNULL,
-                                              cwd=SRCDIR,
-                                              encoding='UTF-8',
-                                              env=env)
+        remote_info = subprocess.check_output(
+            cmd,
+            stderr=subprocess.DEVNULL,
+            cwd=SRCDIR,
+            encoding="UTF-8",
+            env=env,
+        )
     except subprocess.CalledProcessError:
         return None
     for line in remote_info.splitlines():
@@ -115,15 +117,17 @@ def get_git_remote_default_branch(remote_name):
     return None
 
 
-@status("Getting base branch for PR",
-        info=lambda x: x if x is not None else "not a PR branch")
-def get_base_branch():
-    if not os.path.exists(os.path.join(SRCDIR, '.git')):
+@status(
+    "Getting base branch for PR",
+    info=lambda x: x if x is not None else "not a PR branch",
+)
+def get_base_branch() -> Optional[str]:
+    if not os.path.exists(os.path.join(SRCDIR, ".git")):
         # Not a git checkout, so there's no base branch
         return None
     upstream_remote = get_git_upstream_remote()
     version = sys.version_info
-    if version.releaselevel == 'alpha':
+    if version.releaselevel == "alpha":
         base_branch = get_git_remote_default_branch(upstream_remote)
     else:
         base_branch = "{0.major}.{0.minor}".format(version)
@@ -134,38 +138,40 @@ def get_base_branch():
     return upstream_remote + "/" + base_branch
 
 
-@status("Getting the list of files that have been added/changed",
-        info=lambda x: n_files_str(len(x)))
-def changed_files(base_branch=None):
+@status(
+    "Getting the list of files that have been added/changed",
+    info=lambda x: n_files_str(len(x)),
+)
+def changed_files(base_branch: Optional[str] = None) -> list[str]:
     """Get the list of changed or added files from git."""
-    if os.path.exists(os.path.join(SRCDIR, '.git')):
+    if os.path.exists(os.path.join(SRCDIR, ".git")):
         # We just use an existence check here as:
         #  directory = normal git checkout/clone
         #  file = git worktree directory
         if base_branch:
-            cmd = 'git diff --name-status ' + base_branch
+            cmd = "git diff --name-status " + base_branch
         else:
-            cmd = 'git status --porcelain'
+            cmd = "git status --porcelain"
         filenames = []
-        with subprocess.Popen(cmd.split(),
-                              stdout=subprocess.PIPE,
-                              cwd=SRCDIR) as st:
+        with subprocess.Popen(
+            cmd.split(), stdout=subprocess.PIPE, cwd=SRCDIR
+        ) as st:
             git_file_status, _ = st.communicate()
             if st.returncode != 0:
-                sys.exit(f'error running {cmd}')
+                sys.exit(f"error running {cmd}")
             for line in git_file_status.splitlines():
                 line = line.decode().rstrip()
                 status_text, filename = line.split(maxsplit=1)
                 status = set(status_text)
                 # modified, added or unmerged files
-                if not status.intersection('MAU'):
+                if not status.intersection("MAU"):
                     continue
-                if ' -> ' in filename:
+                if " -> " in filename:
                     # file is renamed
-                    filename = filename.split(' -> ', 2)[1].strip()
+                    filename = filename.split(" -> ", 2)[1].strip()
                 filenames.append(filename)
     else:
-        sys.exit('need a git checkout to get modified files')
+        sys.exit("need a git checkout to get modified files")
 
     return list(map(os.path.normpath, filenames))
 
@@ -179,40 +185,45 @@ def docs_modified(file_paths):
 @status("Misc/ACKS updated", modal=True)
 def credit_given(file_paths):
     """Check if Misc/ACKS has been changed."""
-    return os.path.join('Misc', 'ACKS') in file_paths
+    return os.path.join("Misc", "ACKS") in file_paths
 
 
 @status("Misc/NEWS.d updated with `blurb`", modal=True)
 def reported_news(file_paths):
     """Check if Misc/NEWS.d has been changed."""
-    return any(p.startswith(os.path.join('Misc', 'NEWS.d', 'next'))
-               for p in file_paths)
+    return any(
+        p.startswith(os.path.join("Misc", "NEWS.d", "next"))
+        for p in file_paths
+    )
 
 
 @status("configure regenerated", modal=True, info=str)
 def regenerated_configure(file_paths):
     """Check if configure has been regenerated."""
-    if 'configure.ac' in file_paths:
-        return "yes" if 'configure' in file_paths else "no"
+    if "configure.ac" in file_paths:
+        return "yes" if "configure" in file_paths else "no"
     else:
         return "not needed"
 
 
 @status("pyconfig.h.in regenerated", modal=True, info=str)
 def regenerated_pyconfig_h_in(file_paths):
     """Check if pyconfig.h.in has been regenerated."""
-    if 'configure.ac' in file_paths:
-        return "yes" if 'pyconfig.h.in' in file_paths else "no"
+    if "configure.ac" in file_paths:
+        return "yes" if "pyconfig.h.in" in file_paths else "no"
     else:
         return "not needed"
 
 
-def main():
+def main() -> None:
     base_branch = get_base_branch()
     file_paths = changed_files(base_branch)
-    has_doc_files = any(fn for fn in file_paths if fn.startswith('Doc') and
-                        fn.endswith(('.rst', '.inc')))
-    misc_files = {p for p in file_paths if p.startswith('Misc')}
+    has_doc_files = any(
+        fn
+        for fn in file_paths
+        if fn.startswith("Doc") and fn.endswith((".rst", ".inc"))
+    )
+    misc_files = {p for p in file_paths if p.startswith("Misc")}
     # Docs updated.
     docs_modified(has_doc_files)
     # Misc/ACKS changed.
@@ -225,14 +236,14 @@ def main():
     regenerated_pyconfig_h_in(file_paths)
 
     # Test suite run and passed.
-    has_c_files = any(fn for fn in file_paths if fn.endswith(('.c', '.h')))
-    has_python_files = any(fn for fn in file_paths if fn.endswith('.py'))
+    has_c_files = any(fn for fn in file_paths if fn.endswith((".c", ".h")))
+    has_python_files = any(fn for fn in file_paths if fn.endswith(".py"))
     print()
     if has_c_files:
         print("Did you run the test suite and check for refleaks?")
     elif has_python_files:
         print("Did you run the test suite?")
 
 
-if __name__ == '__main__':
+if __name__ == "__main__":
     main()