SPIGOT-7576, #970: Add methods in MushroomCow to change stew effects

By: Doc <nachito94@msn.com>

paper-api/src/main/java/org/bukkit/entity/MushroomCow.java

@@ -1,5 +1,8 @@
 package org.bukkit.entity;
 
+import java.util.List;
+import org.bukkit.potion.PotionEffect;
+import org.bukkit.potion.PotionEffectType;
 import org.jetbrains.annotations.NotNull;
 
 /**
@@ -7,6 +10,63 @@ import org.jetbrains.annotations.NotNull;
  */
 public interface MushroomCow extends Cow {
 
+    /**
+     * Checks for the presence of custom potion effects to be applied to the
+     * next suspicious stew received from milking this {@link MushroomCow}.
+     *
+     * @return true if custom potion effects are applied to the stew
+     */
+    boolean hasEffectsForNextStew();
+
+    /**
+     * Gets an immutable list containing all custom potion effects applied to
+     * the next suspicious stew received from milking this {@link MushroomCow}.
+     * <p>
+     * Plugins should check that hasCustomEffects() returns true before calling
+     * this method.
+     *
+     * @return an immutable list of custom potion effects
+     */
+    @NotNull
+    List<PotionEffect> getEffectsForNextStew();
+
+    /**
+     * Adds a custom potion effect to be applied to the next suspicious stew
+     * received from milking this {@link MushroomCow}.
+     *
+     * @param effect the potion effect to add
+     * @param overwrite true if any existing effect of the same type should be
+     * overwritten
+     * @return true if the effects to be applied to the suspicious stew changed
+     * as a result of this call
+     */
+    boolean addEffectToNextStew(@NotNull PotionEffect effect, boolean overwrite);
+
+    /**
+     * Removes a custom potion effect from being applied to the next suspicious
+     * stew received from milking this {@link MushroomCow}.
+     *
+     * @param type the potion effect type to remove
+     * @return true if the effects to be applied to the suspicious stew changed
+     * as a result of this call
+     */
+    boolean removeEffectFromNextStew(@NotNull PotionEffectType type);
+
+    /**
+     * Checks for a specific custom potion effect type to be applied to the next
+     * suspicious stew received from milking this {@link MushroomCow}.
+     *
+     * @param type the potion effect type to check for
+     * @return true if the suspicious stew to be generated has this effect
+     */
+    boolean hasEffectForNextStew(@NotNull PotionEffectType type);
+
+    /**
+     * Removes all custom potion effects to be applied to the next suspicious
+     * stew received from milking this {@link MushroomCow}.
+     */
+    void clearEffectsForNextStew();
+
     /**
      * Get the variant of this cow.
      *