SPIGOT-2101: Check the result of damageEntity before applying knockback from sweep attacks

nms-patches/EntityHuman.patch

@@ -278,7 +278,20 @@
                          }
                      }
  
-@@ -925,11 +1029,28 @@
+@@ -915,8 +1019,11 @@
+                                 EntityLiving entityliving = (EntityLiving) iterator.next();
+ 
+                                 if (entityliving != this && entityliving != entity && !this.r(entityliving) && this.h(entityliving) < 9.0D) {
++                                    // CraftBukkit start - Only apply knockback if the damage hits
++                                    if (entityliving.damageEntity(DamageSource.playerAttack(this), 1.0F)) {
+                                     entityliving.a(this, 0.4F, (double) MathHelper.sin(this.yaw * 0.017453292F), (double) (-MathHelper.cos(this.yaw * 0.017453292F)));
+-                                    entityliving.damageEntity(DamageSource.playerAttack(this), 1.0F);
++                                    }
++                                    // CraftBukkit end
+                                 }
+                             }
+ 
+@@ -925,11 +1032,28 @@
                          }
  
                          if (entity instanceof EntityPlayer && entity.velocityChanged) {
@@ -307,7 +320,7 @@
                          }
  
                          if (flag2) {
-@@ -991,7 +1112,8 @@
+@@ -991,7 +1115,8 @@
  
                          if (itemstack3 != null && object instanceof EntityLiving) {
                              itemstack3.a((EntityLiving) object, this);
@@ -317,7 +330,7 @@
                                  this.a(EnumHand.MAIN_HAND, (ItemStack) null);
                              }
                          }
-@@ -1001,7 +1123,14 @@
+@@ -1001,7 +1126,14 @@
  
                              this.a(StatisticList.y, Math.round(f5 * 10.0F));
                              if (j > 0) {
@@ -333,7 +346,7 @@
                              }
  
                              if (this.world instanceof WorldServer && f5 > 2.0F) {
-@@ -1090,6 +1219,20 @@
+@@ -1090,6 +1222,20 @@
              this.stopRiding();
          }
  
@@ -354,7 +367,7 @@
          this.setSize(0.2F, 0.2F);
          if (this.world.isLoaded(blockposition)) {
              EnumDirection enumdirection = (EnumDirection) this.world.getType(blockposition).get(BlockFacingHorizontal.FACING);
-@@ -1172,6 +1315,23 @@
+@@ -1172,6 +1318,23 @@
              this.world.everyoneSleeping();
          }
  
@@ -378,7 +391,7 @@
          this.sleepTicks = flag ? 0 : 100;
          if (flag2) {
              this.setRespawnPosition(this.bedPosition, false);
-@@ -1222,9 +1382,11 @@
+@@ -1222,9 +1385,11 @@
          if (blockposition != null) {
              this.e = blockposition;
              this.f = flag;