feat: add ranked season rollover policy

2026-09-16 00:32:21 +00:00 · 2026-08-31 20:29:11 +01:00
parent 1793eb7621
commit cc2cd80a01
16 changed files with 688 additions and 249 deletions
@@ -0,0 +1,59 @@
+package domain
+
+import "testing"
+
+func TestRankedProvisionalBoundaryIsFirstTenGames(t *testing.T) {
+	for games := 0; games < 10; games++ {
+		if !RankedIsProvisional(RankedProfile{RankedGames: games}) {
+			t.Fatalf("game %d should be provisional", games)
+		}
+	}
+	if RankedIsProvisional(RankedProfile{RankedGames: 10}) {
+		t.Fatal("game ten should be fully ranked")
+	}
+}
+
+func TestSeasonRolloverCompressesRatingAndPreservesHistory(t *testing.T) {
+	profile := RankedProfile{Rating: Rating{Value: 1900, RD: 100, Volatility: 0.12}, RankedGames: 25, SeasonHistory: []string{"season-0"}}
+	updated, applied, err := ApplySeasonRollover(profile, "season-1")
+	if err != nil || !applied {
+		t.Fatalf("rollover failed: %+v applied=%v err=%v", updated, applied, err)
+	}
+	if updated.Value != 1800 || updated.RD != 200 || updated.Volatility != profile.Volatility || updated.RankedGames != profile.RankedGames {
+		t.Fatalf("rollover changed wrong fields: %+v", updated)
+	}
+	if len(updated.SeasonHistory) != 2 || updated.SeasonHistory[0] != "season-0" || updated.SeasonHistory[1] != "season-1" {
+		t.Fatalf("history not preserved: %+v", updated.SeasonHistory)
+	}
+}
+
+func TestSeasonRolloverIsExactlyOnceAndCapsRD(t *testing.T) {
+	profile := RankedProfile{Rating: Rating{Value: 1200, RD: 350, Volatility: 0.06}, RankedGames: 4}
+	updated, applied, err := ApplySeasonRollover(profile, "season-1")
+	if err != nil || !applied || updated.Value != 1275 || updated.RD != 350 {
+		t.Fatalf("first rollover wrong: %+v applied=%v err=%v", updated, applied, err)
+	}
+	replay, applied, err := ApplySeasonRollover(updated, "season-1")
+	if err != nil || applied || replay.Value != updated.Value || replay.RD != updated.RD || len(replay.SeasonHistory) != 1 {
+		t.Fatalf("duplicate rollover was not inert: %+v applied=%v err=%v", replay, applied, err)
+	}
+}
+
+func TestSeasonRolloverRejectsInvalidProfileAndReplaysAnyRecordedSeason(t *testing.T) {
+	if _, _, err := ApplySeasonRollover(RankedProfile{RankedGames: -1, Rating: Rating{Value: 1500, RD: 350, Volatility: 0.06}}, "season-1"); err == nil {
+		t.Fatal("negative ranked games should be rejected")
+	}
+	profile := RankedProfile{Rating: Rating{Value: 1600, RD: 250, Volatility: 0.06}, SeasonHistory: []string{"season-1", "season-2"}}
+	updated, applied, err := ApplySeasonRollover(profile, "season-1")
+	if err != nil || applied || updated.Value != profile.Value || updated.RD != profile.RD {
+		t.Fatalf("recorded season replay was not inert: %+v applied=%v err=%v", updated, applied, err)
+	}
+}
+
+func TestCasualRatingHasNoSeasonOperation(t *testing.T) {
+	// The API accepts only RankedProfile, making casual season reset impossible
+	// without an explicit type/compile-time boundary violation.
+	if RankedIsProvisional(RankedProfile{RankedGames: 10}) {
+		t.Fatal("casual boundary test fixture unexpectedly provisional")
+	}
+}