item/stack.go: add option to apply incompatible enchantments (df-mc#1117)

* add ability to enchant item with incompatible enchantments

* accept variadic arguments

* requested

* rename function

* Update server/item/stack.go

Co-authored-by: RestartFU <45609733+RestartFU@users.noreply.github.com>

* Update server/internal/nbtconv/read.go

* Update server/item/stack.go

---------

Co-authored-by: Hashim <hashimssoftware@gmail.com>
Co-authored-by: RestartFU <45609733+RestartFU@users.noreply.github.com>

Author: 3 people

server/internal/nbtconv/read.go

@@ -3,12 +3,13 @@ package nbtconv
 import (
 	"bytes"
 	"encoding/gob"
+	"time"
+
 	"github.com/df-mc/dragonfly/server/block/cube"
 	"github.com/df-mc/dragonfly/server/item"
 	"github.com/df-mc/dragonfly/server/world"
 	"github.com/go-gl/mathgl/mgl64"
 	"golang.org/x/exp/constraints"
-	"time"
 )
 
 // Bool reads a uint8 value from a map at key k and returns true if it equals 1.
@@ -225,7 +226,7 @@ func readEnchantments(m map[string]any, s *item.Stack) {
 	}
 	for _, ench := range enchantments {
 		if t, ok := item.EnchantmentByID(int(Int16(ench, "id"))); ok {
-			*s = s.WithEnchantments(item.NewEnchantment(t, int(Int16(ench, "lvl"))))
+			*s = s.WithForcedEnchantments(item.NewEnchantment(t, int(Int16(ench, "lvl"))))
 		}
 	}
 }

server/item/stack.go

@@ -281,6 +281,17 @@ func (s Stack) WithEnchantments(enchants ...Enchantment) Stack {
 	return s
 }
 
+// WithForcedEnchantments returns the current stack with the passed enchantments applied,
+// bypassing compatibility checks that would normally prevent incompatible enchantments
+// from being applied together.
+func (s Stack) WithForcedEnchantments(enchants ...Enchantment) Stack {
+	s.enchantments = cloneMap(s.enchantments)
+	for _, enchant := range enchants {
+		s.enchantments[enchant.t] = enchant
+	}
+	return s
+}
+
 // WithoutEnchantments returns the current stack but with the passed enchantments removed.
 func (s Stack) WithoutEnchantments(enchants ...EnchantmentType) Stack {
 	s.enchantments = cloneMap(s.enchantments)