feat(mirrors): support URL-only MIRRORS entries and keep git config clean

- Allow MIRRORS to contain plain URLs (one per line) in addition to legacy "NAME URL"
- Treat strings as single URLs to avoid iterable pitfalls
- Write PyPI URLs as metadata-only entries (never added to git config)
- Keep MIRRORS as the single source of truth for mirror setup
- Update integration test to assert URL-only MIRRORS output

https://chatgpt.com/share/6941a9aa-b8b4-800f-963d-2486b34856b1

src/pkgmgr/actions/mirror/io.py

@@ -1,8 +1,9 @@
 from __future__ import annotations
 
 import os
+from collections.abc import Iterable, Mapping
+from typing import Union
 from urllib.parse import urlparse
-from typing import Mapping
 
 from .types import MirrorMap, Repository
 
@@ -32,7 +33,7 @@ def read_mirrors_file(repo_dir: str, filename: str = "MIRRORS") -> MirrorMap:
     """
     Supports:
         NAME URL
-        URL  → auto name = hostname
+        URL  -> auto-generate name from hostname
     """
     path = os.path.join(repo_dir, filename)
     mirrors: MirrorMap = {}
@@ -52,7 +53,8 @@ def read_mirrors_file(repo_dir: str, filename: str = "MIRRORS") -> MirrorMap:
                 # Case 1: "name url"
                 if len(parts) == 2:
                     name, url = parts
-                # Case 2: "url" → auto-generate name
+
+                # Case 2: "url" -> auto name
                 elif len(parts) == 1:
                     url = parts[0]
                     parsed = urlparse(url)
@@ -67,21 +69,56 @@ def read_mirrors_file(repo_dir: str, filename: str = "MIRRORS") -> MirrorMap:
                     continue
 
                 mirrors[name] = url
+
     except OSError as exc:
         print(f"[WARN] Could not read MIRRORS file at {path}: {exc}")
 
     return mirrors
 
 
+MirrorsInput = Union[Mapping[str, str], Iterable[str]]
+
+
 def write_mirrors_file(
     repo_dir: str,
-    mirrors: Mapping[str, str],
+    mirrors: MirrorsInput,
     filename: str = "MIRRORS",
     preview: bool = False,
 ) -> None:
+    """
+    Write MIRRORS in one of two formats:
 
+    1) Mapping[str, str] -> "NAME URL" per line (legacy / compatible)
+    2) Iterable[str]     -> "URL" per line (new preferred)
+
+    Strings are treated as a single URL (not iterated character-by-character).
+    """
     path = os.path.join(repo_dir, filename)
-    lines = [f"{name} {url}" for name, url in sorted(mirrors.items())]
+
+    lines: list[str]
+
+    if isinstance(mirrors, Mapping):
+        items = [
+            (str(name), str(url))
+            for name, url in mirrors.items()
+            if url is not None and str(url).strip()
+        ]
+        items.sort(key=lambda x: (x[0], x[1]))
+        lines = [f"{name} {url}" for name, url in items]
+
+    else:
+        if isinstance(mirrors, (str, bytes)):
+            urls = [str(mirrors).strip()]
+        else:
+            urls = [
+                str(url).strip()
+                for url in mirrors
+                if url is not None and str(url).strip()
+            ]
+
+        urls = sorted(set(urls))
+        lines = urls
+
     content = "\n".join(lines) + ("\n" if lines else "")
 
     if preview:
@@ -94,5 +131,6 @@ def write_mirrors_file(
         with open(path, "w", encoding="utf-8") as fh:
             fh.write(content)
         print(f"[INFO] Wrote MIRRORS file at {path}")
+
     except OSError as exc:
         print(f"[ERROR] Failed to write MIRRORS file at {path}: {exc}")

src/pkgmgr/actions/repository/create/mirrors.py

@@ -12,8 +12,8 @@ class MirrorBootstrapper:
     """
     MIRRORS is the single source of truth.
 
-    We write defaults to MIRRORS and then call mirror setup which will
-    configure git remotes based on MIRRORS content (but only for git URLs).
+    Defaults are written to MIRRORS and mirror setup derives
+    git remotes exclusively from that file (git URLs only).
     """
 
     def write_defaults(
@@ -25,10 +25,8 @@ class MirrorBootstrapper:
         preview: bool,
     ) -> None:
         mirrors = {
-            # preferred SSH url is supplied by CreateRepoPlanner.primary_remote
-            "origin": primary,
-            # metadata only: must NEVER be configured as a git remote
-            "pypi": f"https://pypi.org/project/{name}/",
+            primary,
+            f"https://pypi.org/project/{name}/",
         }
         write_mirrors_file(repo_dir, mirrors, preview=preview)
 
@@ -41,7 +39,8 @@ class MirrorBootstrapper:
         preview: bool,
         remote: bool,
     ) -> None:
-        # IMPORTANT: do NOT set repo["mirrors"] here.
+        # IMPORTANT:
+        # Do NOT set repo["mirrors"] here.
         # MIRRORS file is the single source of truth.
         setup_mirrors(
             selected_repos=[repo],

tests/integration/test_repos_create_pypi_not_in_git_config.py

@@ -75,12 +75,12 @@ class TestCreateRepoPypiNotInGitConfig(unittest.TestCase):
 
             mirrors_content = mirrors_file.read_text(encoding="utf-8")
             self.assertIn(
-                "pypi https://pypi.org/project/repo/",
+                "https://pypi.org/project/repo/",
                 mirrors_content,
                 "PyPI mirror entry must exist in MIRRORS",
             )
             self.assertIn(
-                "origin git@github.com:acme/repo.git",
+                "git@github.com:acme/repo.git",
                 mirrors_content,
                 "origin SSH URL must exist in MIRRORS",
             )