Support script to audit, remove dotfile symlinks

Adding a simple script to help me manage the symlinks to the dotfiles
managed by my mono-repo.

python/delete_dotfile_symlinks.py

@@ -0,0 +1,88 @@
+#!/usr/bin/env python3
+
+# TODO: Prefer a proper Python module doc here.
+# Find and delete all symlinks to the dotfiles defined in $BRIEFCASE.
+#
+# Oftentimes I corrupt the state of my dotfiles. The intention with this script
+# is to write some tooling to help me better manage my dotfile cleanliness. An
+# example workflow might look like:
+#
+# ```shell
+# > ./delete_dotfile_symlinks.py --audit
+# > ./delete_dotfile_symlinks.py --seriously
+# > cd ..
+# > make install
+# ```
+
+################################################################################
+# Dependencies
+################################################################################
+
+import argparse
+import os
+import sys
+
+from os.path import expanduser
+
+################################################################################
+# Library
+################################################################################
+
+def homify(path):
+  """Prefer ~ instead of the absolute `path`."""
+  home = expanduser('~')
+  return path.replace(home, '~')
+
+def main():
+  parser = argparse.ArgumentParser(description='Remove symlinks to my managed dotfiles.')
+  parser.add_argument('--audit', dest='audit', action='store_true', help='Output all symlinks that would be deleted. This is the default behavior. This option is mutually exclusive with the --seriously option.')
+  parser.add_argument('--seriously', dest='seriously', action='store_true', help='Actually delete the symlinks. This option is mutually exclusive with the --audit option.')
+  parser.add_argument('--repo-name', dest='name', default='briefcase', help='The name of the repository. Usually "briefcase" or "dotfiles".')
+  parser.add_argument('--device-only', dest='device_only', action='store_true', help='Only output the device-specific dotfiles.')
+  args = parser.parse_args()
+
+  # TODO: Instead of doing this manually, is this something that argparse supports?
+  if not args.audit and not args.seriously:
+     print('Either --audit or --seriously must be passed. See --help for more information.')
+     # TODO: What's the proper exit code here?
+     sys.exit(1)
+
+  # These two options are mutually exclusive.
+  assert args.audit != args.seriously
+
+  count = 0
+
+  for cwd, dirs, files in os.walk(expanduser("~")):
+    # Skip this repository.
+    if args.name in cwd:
+      continue
+    for file in files:
+      source = os.path.join(cwd, file)
+      if os.path.islink(source):
+        dest = os.readlink(source)
+        # We won't know certainly if the link points to a dotfile that I manage
+        # with this simple test.
+        if args.device_only:
+          # TODO: Change 'desktop' with a lookup of hostname to device name.
+          if 'configs/desktop' in dest:
+            if args.audit:
+              print('{} -> {}'.format(homify(source), homify(dest)))
+            elif args.seriously:
+              print('rm {}'.format(source))
+              os.remove(source)
+            count += 1
+        elif args.name in dest:
+          if args.audit:
+            print('{} -> {}'.format(homify(source), homify(dest)))
+          elif args.seriously:
+            print('rm {}'.format(source))
+            os.remove(source)
+          count += 1
+
+  if args.audit:
+    print('Would have deleted {} symlinks.'.format(count))
+  elif args.seriously:
+    print('Successfully deleted {} symlinks.'.format(count))
+
+if __name__ == '__main__':
+   main()