fix(bundler): fall back to packaged catalog snapshot

Assisted-by: GitHub Copilot (model: gpt-5.6-luna, autonomous)

Author: Markus

src/specify_cli/bundler/services/adapters.py

@@ -143,7 +143,16 @@ def fetch(source: CatalogSource) -> dict:
             if repository_url is None:
                 raise BundlerError(f"Unknown built-in catalog '{url}'.")
             if allow_network:
-                return _http_get_json(source.id, repository_url)
+                try:
+                    return _http_get_json(source.id, repository_url)
+                except BundlerError as exc:
+                    # Built-in catalogs remain usable when the repository is
+                    # temporarily unavailable; the packaged snapshot is the
+                    # authoritative offline fallback.
+                    try:
+                        return _load_packaged_catalog(_BUILTIN_PACKAGED_SNAPSHOTS[url])
+                    except BundlerError as snapshot_exc:
+                        raise snapshot_exc from exc
             return _load_packaged_catalog(_BUILTIN_PACKAGED_SNAPSHOTS[url])
 
         if scheme == "file":
@@ -204,7 +213,7 @@ def _validate_redirect(_old_url: str, new_url: str) -> None:
             ).decode("utf-8")
     except BundlerError:
         raise
-    except Exception as exc:  # noqa: BLE001
+    except Exception as exc:
         raise BundlerError(f"Failed to fetch catalog from {url}: {exc}") from exc
     return loads_json(raw, origin=final_url)
 

tests/integration/test_bundler_offline.py

@@ -41,6 +41,36 @@ def test_builtin_default_catalog_resolves_first_party_bundles_offline():
     assert resolved.install_allowed is True
 
 
+def test_builtin_catalog_failure_does_not_block_lower_priority_source(monkeypatch):
+    def fail_http_get_json(source_id, url):
+        raise BundlerError("repository unavailable")
+
+    monkeypatch.setattr(
+        "specify_cli.bundler.services.adapters._http_get_json", fail_http_get_json
+    )
+    monkeypatch.setattr(
+        "specify_cli.bundler.services.adapters._load_packaged_catalog",
+        lambda filename: {"schema_version": "1.0", "bundles": {}},
+    )
+
+    project = _src("project", "https://example.com/catalog.json", priority=10)
+    fetcher = make_catalog_fetcher(allow_network=True)
+
+    def fetch_project(source):
+        if source.id == "project":
+            return {
+                "schema_version": "1.0",
+                "bundles": {"company": catalog_entry_dict("company")},
+            }
+        return fetcher(source)
+
+    stack = CatalogStack(
+        [_src("default", "builtin://default"), project], fetch_project
+    )
+
+    assert stack.resolve("company").source.id == "project"
+
+
 def test_builtin_community_catalog_resolves_from_packaged_snapshot_offline():
     fetcher = make_catalog_fetcher(allow_network=False)
     source = _src(

tests/unit/test_bundler_adapters.py

@@ -1,6 +1,8 @@
 """Unit tests for catalog-fetch adapters (auth + redirect safety)."""
 from __future__ import annotations
 
+from typing import Self
+
 import pytest
 
 from specify_cli.bundler import BundlerError
@@ -23,7 +25,7 @@ def __init__(self, body: bytes, final_url: str) -> None:
         self._offset = 0
         self._final_url = final_url
 
-    def __enter__(self) -> "_FakeResponse":
+    def __enter__(self) -> Self:
         return self
 
     def __exit__(self, *exc) -> bool:
@@ -136,6 +138,33 @@ def fake_http_get_json(source_id, url):
     }
 
 
+def test_builtin_default_catalog_falls_back_to_core_pack_on_fetch_error(
+    monkeypatch, tmp_path
+):
+    catalog_path = tmp_path / "bundles" / "catalog.json"
+    catalog_path.parent.mkdir()
+    catalog_path.write_text(
+        '{"schema_version":"1.0","bundles":{"packaged":{'
+        '"id":"packaged","name":"Packaged","version":"1.0.0",'
+        '"role":"developer","description":"Packaged catalog entry.",'
+        '"author":"Spec Kit","license":"MIT","download_url":"",'
+        '"requires":{"speckit_version":">=0.1.0"},'
+        '"provides":{},"verified":false}}}',
+        encoding="utf-8",
+    )
+    monkeypatch.setattr(adapters, "_locate_core_pack", lambda: tmp_path)
+
+    def fail_http_get_json(source_id, url):
+        raise BundlerError("repository unavailable")
+
+    monkeypatch.setattr(adapters, "_http_get_json", fail_http_get_json)
+
+    fetcher = adapters.make_catalog_fetcher(allow_network=True)
+    result = fetcher(_source("builtin://default"))
+
+    assert "packaged" in result["bundles"]
+
+
 def test_builtin_default_catalog_uses_core_pack_snapshot_offline(monkeypatch, tmp_path):
     catalog_path = tmp_path / "bundles" / "catalog.json"
     catalog_path.parent.mkdir()