fix(metricsai): query reactors, not the removed users field, for review reactions

metricsai/src/metricsai/sources/github.py

@@ -479,8 +479,10 @@ def _review_reactions(requester: object, raw: dict) -> tuple[int, int]:
 
     REST omits reactions for pull-request reviews (there is no reactions endpoint for
     them), so the summary-level 👍/👎 is only reachable through GraphQL -- ``PullRequestReview``
-    implements the ``Reactable`` interface. A missing node id, a GraphQL/permission error,
-    or a network failure degrades quietly to ``(0, 0)`` rather than aborting the scan.
+    implements the ``Reactable`` interface. The per-group total comes from ``reactors`` (the
+    ``users`` field GitHub once exposed here was removed in 2021); a missing node id, a
+    GraphQL/permission error, or a network failure degrades quietly to ``(0, 0)`` rather than
+    aborting the scan.
 
     :param requester: The PyGithub ``Requester`` (``Github.requester``).
     :param raw: The review's ``raw_data`` (its ``node_id`` keys the GraphQL node lookup).
@@ -491,15 +493,16 @@ def _review_reactions(requester: object, raw: dict) -> tuple[int, int]:
         return 0, 0
     try:
         _, resp = requester.graphql_node(
-            node_id, "reactionGroups { content users { totalCount } }", "PullRequestReview"
+            node_id, "reactionGroups { content reactors { totalCount } }", "PullRequestReview"
         )
     except Exception as exc:  # GraphQL / permission / network errors must not abort the scan.
         logger.debug("review reactions lookup failed for %s: %s", node_id, exc)
         return 0, 0
     node = ((resp or {}).get("data") or {}).get("node") or {}
     up = down = 0
     for group in node.get("reactionGroups") or []:
-        total = int((group.get("users") or {}).get("totalCount") or 0)
+        # ``reactors`` is the current field; fall back to the legacy ``users`` for old GHE.
+        total = int((group.get("reactors") or group.get("users") or {}).get("totalCount") or 0)
         if group.get("content") == "THUMBS_UP":
             up = total
         elif group.get("content") == "THUMBS_DOWN":

metricsai/tests/test_github_source.py

@@ -174,12 +174,17 @@ def get_repo(self, name):
 
 
 class _FakeRequester:
-    """Stub GitHub requester returning fixed reaction totals for ``graphql_node``."""
+    """Stub GitHub requester returning fixed reaction totals for ``graphql_node``.
 
-    def __init__(self, up: int = 0, down: int = 0):
+    Uses the current ``reactors`` field (the ``users`` field was removed from
+    ``ReactionGroup`` in 2021); ``legacy=True`` emulates an old GHE that still serves ``users``.
+    """
+
+    def __init__(self, up: int = 0, down: int = 0, *, legacy: bool = False):
+        key = "users" if legacy else "reactors"
         self._groups = [
-            {"content": "THUMBS_UP", "users": {"totalCount": up}},
-            {"content": "THUMBS_DOWN", "users": {"totalCount": down}},
+            {"content": "THUMBS_UP", key: {"totalCount": up}},
+            {"content": "THUMBS_DOWN", key: {"totalCount": down}},
         ]
 
     def graphql_node(self, node_id, output_schema, node_type):
@@ -252,6 +257,14 @@ def test_scan_review_offdiff_respects_author_and_window() -> None:
     assert _offdiff(wrong_author, _FakeRequester(0, 0), match_all_authors=True)
 
 
+def test_review_reactions_reads_reactors_and_maps_down_correctly() -> None:
+    # The 👎 must land in thumbs_down, not thumbs_up (regression: wrong content mapping).
+    assert github._review_reactions(_FakeRequester(0, 3), {"node_id": "R_1"}) == (0, 3)
+    assert github._review_reactions(_FakeRequester(2, 0), {"node_id": "R_1"}) == (2, 0)
+    # Legacy GHE still serving the old ``users`` field is read via the fallback.
+    assert github._review_reactions(_FakeRequester(1, 4, legacy=True), {"node_id": "R_1"}) == (1, 4)
+
+
 def test_review_reactions_degrades_to_zero() -> None:
     assert github._review_reactions(_FakeRequester(1, 1), {}) == (0, 0)  # no node_id
     assert github._review_reactions(None, {"node_id": "R_1"}) == (0, 0)  # no requester