fix preflight

build/release/version.py

@@ -5,12 +5,16 @@ from __future__ import annotations
 import json
 import os
 import re
+import subprocess
 import urllib.error
 import urllib.request
 from pathlib import Path
 
 PYPI_JSON_URL = "https://pypi.org/pypi/orisys/json"
 
+# Sibling repository that carries the public GitHub releases and their tags.
+RELEASE_REPO_DIRNAME = "orisys-sdk-release"
+
 # orisys-<version>-<pytag>-<abitag>-<platformtag>.whl
 _WHEEL_NAME_RE = re.compile(r"^orisys-(?P<version>[^-]+)-[^-]+-[^-]+-.+\.whl$")
 
@@ -103,6 +107,42 @@ def _version_sort_key(name: str):
     return ([int(part) for part in parts] or [0], name)
 
 
+def git_tags(repo_root: Path) -> list[str]:
+    """Local git tags from this repo and the sibling release repo.
+
+    Tags are the only offline evidence that a version was already released
+    (``v0.5.1`` in ``orisys-sdk-release`` marks a published GitHub release), so
+    the duplicate guard works without network access.
+    """
+    roots = [Path(repo_root)]
+    sibling = Path(repo_root).parent / RELEASE_REPO_DIRNAME
+    if sibling.is_dir():
+        roots.append(sibling)
+
+    tags: set[str] = set()
+    for root in roots:
+        try:
+            completed = subprocess.run(
+                ["git", "-C", str(root), "tag", "--list"],
+                capture_output=True,
+                text=True,
+                check=False,
+            )
+        except OSError:
+            continue
+        if completed.returncode != 0:
+            continue
+        tags.update(
+            line.strip() for line in (completed.stdout or "").splitlines() if line.strip()
+        )
+    return sorted(tags)
+
+
+def released_tags_for(version: str, tags: list[str]) -> list[str]:
+    """Tag spellings that mark ``version`` as already released."""
+    return sorted({version, f"v{version}"} & set(tags))
+
+
 def conda_envs_root() -> Path | None:
     """Locate the conda envs directory the same way build/wheel/win.bat does."""
     override = os.getenv("CONDA_ENVS_ROOT")