Fix the team resolve properly: backfill the name BEFORE confirmation

My first attempt did not work in prod -- team stayed 0/323 after deploy.
I resolved the team name AFTER the hint-confirmation check, but the check
itself reads hit.currentTeam.name, which is undefined because
/sports/1/players returns { id, link }. With a FULL-NAME hint (what
snapshotService passes) neither branch of teamRecordMatchesHint could
match: the name branch had no name, and the abbr branch cannot resolve a
full name to an abbr. Confirmation failed, the team was nulled, and my
later backfill ran on an already-null value.

withTeamName() now backfills the name from the cached /teams list BEFORE
any comparison, and is used at all three confirmation sites plus the
return. Verified against the live API on all four cases: no hint, FULL-NAME
hint, abbr hint -> "Philadelphia Phillies"; WRONG hint -> null.

That last case matters most: a wrong hint must still REFUSE. The
confirmation exists so a namesake collision cannot tag a player to a team
he is not on, which would fabricate opponents downstream. Making the match
succeed must not make it succeed wrongly, and a test locks it.

Gates: 4,087 tests / 327 suites green; next build exit 0.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01QJs13VsyiSKYQP6rj3NNmc

src/services/adapters/mlbStatsAdapter.js

@@ -216,6 +216,21 @@ function teamNorm(s) {
  * teams = the cached statsapi `/teams` list ([{ id, abbr, name }]) used to turn
  * an abbr hint into a team id.
  */
+/**
+ * `/sports/1/players` returns `currentTeam: { id, link }` with NO `name`, so a
+ * raw currentTeam cannot be matched against a FULL-NAME hint and cannot be
+ * reported as a team. Backfill the name from the cached `/teams` list (id is
+ * present on 100% of the player list) BEFORE any comparison — doing it after
+ * the confirmation check leaves the check failing and nulls the team anyway,
+ * which is exactly how `team` ended up null on 416/416 graded rows.
+ */
+function withTeamName(currentTeam, teams) {
+  if (!currentTeam || currentTeam.id == null) return null;
+  if (currentTeam.name) return { id: currentTeam.id, name: currentTeam.name };
+  const row = (teams || []).find((t) => t.id === currentTeam.id);
+  return { id: currentTeam.id, name: (row && row.name) || null };
+}
+
 function teamRecordMatchesHint(team, teamHint, teams) {
   if (!team || !Array.isArray(teamHint) || teamHint.length === 0) return false;
   const tId = team.id;
@@ -237,7 +252,7 @@ function teamRecordMatchesHint(team, teamHint, teams) {
 function disambiguateByHint(candidates, teamHint, teams) {
   if (!Array.isArray(teamHint) || teamHint.length === 0) return null;
   const matches = (candidates || []).filter((p) =>
-    p.currentTeam && teamRecordMatchesHint({ id: p.currentTeam.id, name: p.currentTeam.name }, teamHint, teams));
+    p.currentTeam && teamRecordMatchesHint(withTeamName(p.currentTeam, teams), teamHint, teams));
   return matches.length === 1 ? matches[0] : null;
 }
 
@@ -288,8 +303,8 @@ async function searchPlayer(name, season = DEFAULT_SEASON, opts = {}) {
   if (exact.length === 1) {
     hit = exact[0];
     if (teamHint && hit.currentTeam) {
-      teamConfirmed = teamRecordMatchesHint(
-        { id: hit.currentTeam.id, name: hit.currentTeam.name }, teamHint, await ensureTeams());
+      const tms = await ensureTeams();
+      teamConfirmed = teamRecordMatchesHint(withTeamName(hit.currentTeam, tms), teamHint, tms);
     }
   } else if (exact.length >= 2) {
     // Namesake collision — resolve ONLY with a confident hint, else refuse.
@@ -298,8 +313,8 @@ async function searchPlayer(name, season = DEFAULT_SEASON, opts = {}) {
   } else {
     hit = lastNameInitialFallback(people, targetKey);
     if (hit && teamHint && hit.currentTeam) {
-      teamConfirmed = teamRecordMatchesHint(
-        { id: hit.currentTeam.id, name: hit.currentTeam.name }, teamHint, await ensureTeams());
+      const tms = await ensureTeams();
+      teamConfirmed = teamRecordMatchesHint(withTeamName(hit.currentTeam, tms), teamHint, tms);
     }
   }
 
@@ -313,14 +328,13 @@ async function searchPlayer(name, season = DEFAULT_SEASON, opts = {}) {
   //
   // The id is present on 100% of the list, and the /teams list (already cached
   // 24h) maps id -> name, so this costs no new request.
-  const teamId = teamConfirmed ? (hit.currentTeam?.id ?? null) : null;
-  let teamName = teamConfirmed ? (hit.currentTeam?.name ?? null) : null;
-  if (teamName == null && teamId != null) {
-    try {
-      const row = (await ensureTeams()).find((t) => t.id === teamId);
-      if (row && row.name) teamName = row.name;
-    } catch { /* honest-absent: an unresolved team stays null, never guessed */ }
+  let resolvedTeam = null;
+  if (teamConfirmed && hit.currentTeam) {
+    try { resolvedTeam = withTeamName(hit.currentTeam, await ensureTeams()); }
+    catch { resolvedTeam = null; /* honest-absent: never guessed */ }
   }
+  const teamId = resolvedTeam ? resolvedTeam.id : null;
+  const teamName = resolvedTeam ? resolvedTeam.name : null;
   return {
     id: hit.id,
     fullName: hit.fullName ?? name,
@@ -443,5 +457,7 @@ module.exports = {
     BASE, TTL, extractSplits, ymd, DEFAULT_SEASON,
     // Wave 1 — pure namesake-disambiguation helpers (unit-tested with fixtures).
     canonAbbr, teamNorm, teamRecordMatchesHint, disambiguateByHint, lastNameInitialFallback,
+    // 2026-08-01 — the team-name backfill the S59 invariant depends on.
+    withTeamName,
   },
 };

tests/unit/slateJoinInvariant.test.js

@@ -66,3 +66,37 @@ describe('the invariant’s input is the PLAYER team, not the prop’s own game'
     expect(players(out)).toEqual(['X']);   // abstained — no player team known
   });
 });
+
+describe('mlbStatsAdapter — the team the invariant depends on', () => {
+  const { __internals } = require('../../src/services/adapters/mlbStatsAdapter');
+  const { withTeamName, teamRecordMatchesHint } = __internals || {};
+  const TEAMS = [{ id: 143, abbr: 'PHI', name: 'Philadelphia Phillies' },
+                 { id: 141, abbr: 'TOR', name: 'Toronto Blue Jays' }];
+
+  it('backfills the team NAME from the id — the list returns { id, link } only', () => {
+    expect(withTeamName({ id: 143, link: '/api/v1/teams/143' }, TEAMS))
+      .toEqual({ id: 143, name: 'Philadelphia Phillies' });
+  });
+
+  it('returns null for an absent team rather than an empty shell', () => {
+    expect(withTeamName(null, TEAMS)).toBeNull();
+    expect(withTeamName({ link: '/x' }, TEAMS)).toBeNull();
+  });
+
+  it('leaves the name null when the id is unknown — never guessed', () => {
+    expect(withTeamName({ id: 999 }, TEAMS)).toEqual({ id: 999, name: null });
+  });
+
+  it('a FULL-NAME hint now matches — this is what was silently failing', () => {
+    // Before the backfill, name was undefined, so a full-name hint could match
+    // neither branch: confirmation failed and the team was nulled.
+    const t = withTeamName({ id: 143 }, TEAMS);
+    expect(teamRecordMatchesHint(t, ['Philadelphia Phillies', 'New York Mets'], TEAMS)).toBe(true);
+    expect(teamRecordMatchesHint(t, ['PHI'], TEAMS)).toBe(true);
+  });
+
+  it('a WRONG hint still REFUSES — the anti-fabrication guard is preserved', () => {
+    const t = withTeamName({ id: 143 }, TEAMS);
+    expect(teamRecordMatchesHint(t, ['Toronto Blue Jays'], TEAMS)).toBe(false);
+  });
+});