Remove player entries on leave/death prior to session start.

While we do want to keep track of join and ready times, we really don't
care about those stats for players who join the lobby _and leave_ prior
to the arena actually starting.

Coincidentally, _not_ storing stats for players that don't actually pick
a class means we don't end up trying to insert a `null` value into the
class name column, which should solve the error thrown when trying to do
just that as a result of the auto-start timer kicking players or players
themselves leaving prior to starting.

Fixes #16

src/main/java/org/mobarena/stats/session/Session.java

@@ -47,6 +47,11 @@ public class Session {
 
     public void playerLeave(Arena arena, Player player) {
         UUID playerId = player.getUniqueId();
+        if (sessionStats.startTime == null) {
+            playerStats.remove(playerId);
+            return;
+        }
+
         PlayerSessionStats stats = playerStats.get(playerId);
         if (stats == null) {
             return;
@@ -63,6 +68,11 @@ public class Session {
 
     public void playerDeath(Arena arena, Player player) {
         UUID playerId = player.getUniqueId();
+        if (sessionStats.startTime == null) {
+            playerStats.remove(playerId);
+            return;
+        }
+
         PlayerSessionStats stats = playerStats.get(playerId);
         if (stats == null) {
             return;

src/test/java/org/mobarena/stats/session/SessionTest.java

@@ -95,6 +95,19 @@ class SessionTest {
         assertThat(actual.className, equalTo(className));
     }
 
+    @Test
+    void removeFromSessionOnLeaveBeforeStart() {
+        UUID playerId = UUID.fromString("cafebabe-ea75-dead-beef-deadcafebabe");
+        Player player = Mocks.player(playerId, "garbagemule");
+        Arena arena = mock(Arena.class);
+        subject.playerJoin(player);
+
+        subject.playerLeave(arena, player);
+
+        PlayerSessionStats actual = subject.getPlayerStats(playerId);
+        assertThat(actual, nullValue());
+    }
+
     @Test
     void setLeaveTimeOnLeave() {
         UUID playerId = UUID.fromString("cafebabe-ea75-dead-beef-deadcafebabe");
@@ -103,6 +116,7 @@ class SessionTest {
         ArenaPlayer ap = mock(ArenaPlayer.class);
         when(arena.getArenaPlayer(player)).thenReturn(ap);
         subject.playerJoin(player);
+        subject.start();
 
         subject.playerLeave(arena, player);
 
@@ -118,6 +132,7 @@ class SessionTest {
         ArenaPlayer ap = mock(ArenaPlayer.class);
         when(arena.getArenaPlayer(player)).thenReturn(ap);
         subject.playerJoin(player);
+        subject.start();
 
         subject.playerLeave(arena, player);
 
@@ -133,6 +148,7 @@ class SessionTest {
         ArenaPlayer ap = mock(ArenaPlayer.class);
         when(arena.getArenaPlayer(player)).thenReturn(ap);
         subject.playerJoin(player);
+        subject.start();
         subject.getPlayerStats(playerId).conclusion = PlayerConclusion.VICTORY;
 
         subject.playerLeave(arena, player);
@@ -141,6 +157,19 @@ class SessionTest {
         assertThat(actual.conclusion, not(equalTo(PlayerConclusion.RETREAT)));
     }
 
+    @Test
+    void removeFromSessionOnDeathBeforeStart() {
+        UUID playerId = UUID.fromString("cafebabe-ea75-dead-beef-deadcafebabe");
+        Player player = Mocks.player(playerId, "garbagemule");
+        Arena arena = mock(Arena.class);
+        subject.playerJoin(player);
+
+        subject.playerDeath(arena, player);
+
+        PlayerSessionStats actual = subject.getPlayerStats(playerId);
+        assertThat(actual, nullValue());
+    }
+
     @Test
     void setDeathTimeOnDeath() {
         UUID playerId = UUID.fromString("cafebabe-ea75-dead-beef-deadcafebabe");
@@ -149,6 +178,7 @@ class SessionTest {
         ArenaPlayer ap = mock(ArenaPlayer.class);
         when(arena.getArenaPlayer(player)).thenReturn(ap);
         subject.playerJoin(player);
+        subject.start();
 
         subject.playerDeath(arena, player);
 
@@ -164,6 +194,7 @@ class SessionTest {
         ArenaPlayer ap = mock(ArenaPlayer.class);
         when(arena.getArenaPlayer(player)).thenReturn(ap);
         subject.playerJoin(player);
+        subject.start();
 
         subject.playerDeath(arena, player);
 
@@ -179,6 +210,7 @@ class SessionTest {
         ArenaPlayer ap = mock(ArenaPlayer.class);
         when(arena.getArenaPlayer(player)).thenReturn(ap);
         subject.playerJoin(player);
+        subject.start();
         subject.getPlayerStats(playerId).conclusion = PlayerConclusion.VICTORY;
 
         subject.playerDeath(arena, player);
@@ -246,6 +278,7 @@ class SessionTest {
         when(arena.getArenaPlayer(corpse)).thenReturn(ap);
         subject.playerJoin(corpse);
         subject.playerJoin(survivor);
+        subject.start();
         subject.playerDeath(arena, corpse);
 
         subject.complete();