Fix best of calculation for low number of teams

app/features/tournament-bracket/core/bestOf.server.ts

@@ -8,6 +8,12 @@ export function resolveBestOfs(
   // 3 is default
   const result: [bestOf: 5 | 7, id: number][] = [];
 
+  // special case: only 2 teams
+  if (matches.length === 1) {
+    result.push([7, matches[0]!.matchId]);
+    return result;
+  }
+
   /// Best of 7
 
   // 1) Grand Finals
@@ -45,7 +51,8 @@ export function resolveBestOfs(
   );
 
   const losersFinals = matches.filter(
-    (match) => match.roundNumber === maxLosersRoundNumber
+    (match) =>
+      match.roundNumber === maxLosersRoundNumber && match.groupNumber === 2
   );
   invariant(losersFinals.length === 1, "losersFinals must be 1");
 

app/features/tournament-bracket/core/bestOf.test.ts

@@ -0,0 +1,61 @@
+import { suite } from "uvu";
+import * as assert from "uvu/assert";
+import { resolveBestOfs } from "./bestOf.server";
+
+const ResolveBestOfs = suite("resolveBestOfs()");
+
+const count = (bestOfs: [bestOf: 5 | 7, id: number][], target: 5 | 7) =>
+  bestOfs.reduce((acc, cur) => acc + (cur[0] === target ? 1 : 0), 0);
+
+ResolveBestOfs("2 teams", () => {
+  const matches = [{ matchId: 1, roundNumber: 1, groupNumber: 1 }];
+
+  const bestOfs = resolveBestOfs(matches);
+
+  assert.equal(count(bestOfs, 5), 0);
+  assert.equal(count(bestOfs, 7), 1);
+});
+
+ResolveBestOfs("4 teams", () => {
+  const matches = [
+    { matchId: 1, roundNumber: 1, groupNumber: 1 },
+    { matchId: 2, roundNumber: 1, groupNumber: 1 },
+    { matchId: 3, roundNumber: 2, groupNumber: 1 },
+    { matchId: 4, roundNumber: 1, groupNumber: 2 },
+    { matchId: 5, roundNumber: 2, groupNumber: 2 },
+    { matchId: 6, roundNumber: 1, groupNumber: 3 },
+    { matchId: 7, roundNumber: 2, groupNumber: 3 },
+  ];
+
+  const bestOfs = resolveBestOfs(matches);
+
+  assert.equal(count(bestOfs, 5), 1);
+  assert.equal(count(bestOfs, 7), 2);
+});
+
+ResolveBestOfs("8 teams", () => {
+  const matches = [
+    { matchId: 1, roundNumber: 1, groupNumber: 1 },
+    { matchId: 2, roundNumber: 1, groupNumber: 1 },
+    { matchId: 3, roundNumber: 1, groupNumber: 1 },
+    { matchId: 4, roundNumber: 1, groupNumber: 1 },
+    { matchId: 5, roundNumber: 2, groupNumber: 1 },
+    { matchId: 6, roundNumber: 2, groupNumber: 1 },
+    { matchId: 7, roundNumber: 3, groupNumber: 1 },
+    { matchId: 8, roundNumber: 1, groupNumber: 2 },
+    { matchId: 9, roundNumber: 1, groupNumber: 2 },
+    { matchId: 10, roundNumber: 2, groupNumber: 2 },
+    { matchId: 11, roundNumber: 2, groupNumber: 2 },
+    { matchId: 12, roundNumber: 3, groupNumber: 2 },
+    { matchId: 13, roundNumber: 4, groupNumber: 2 },
+    { matchId: 14, roundNumber: 1, groupNumber: 3 },
+    { matchId: 15, roundNumber: 2, groupNumber: 3 },
+  ];
+
+  const bestOfs = resolveBestOfs(matches);
+
+  assert.equal(count(bestOfs, 5), 2);
+  assert.equal(count(bestOfs, 7), 2);
+});
+
+ResolveBestOfs.run();