🎨 Move HAS_EXTRUDERS

Marlin/src/inc/Conditionals_LCD.h

@@ -538,7 +538,12 @@
  *  E_MANUAL     - Number of E steppers for LCD move options
  */
 
-#if EXTRUDERS == 0
+#if EXTRUDERS
+  #define HAS_EXTRUDERS 1
+  #if EXTRUDERS > 1
+    #define HAS_MULTI_EXTRUDER 1
+  #endif
+#else
   #undef EXTRUDERS
   #define EXTRUDERS 0
   #undef SINGLENOZZLE
@@ -546,8 +551,6 @@
   #undef SWITCHING_NOZZLE
   #undef MIXING_EXTRUDER
   #undef HOTEND_IDLE_TIMEOUT
-#elif EXTRUDERS > 1
-  #define HAS_MULTI_EXTRUDER 1
 #endif
 
 #if ENABLED(SWITCHING_EXTRUDER)   // One stepper for every two EXTRUDERS
@@ -663,7 +666,7 @@
  * All the logical axes that can be commanded directly by G-code.
  * Delta maps stepper-specific values to ABC steppers.
  */
-#if EXTRUDERS
+#if HAS_EXTRUDERS
   #define LOGICAL_AXES INCREMENT(LINEAR_AXES)
 #else
   #define LOGICAL_AXES LINEAR_AXES

Marlin/src/inc/Conditionals_adv.h

@@ -75,7 +75,7 @@
   #define SERVO_DELAY { 50 }
 #endif
 
-#if EXTRUDERS == 0
+#if !HAS_EXTRUDERS
   #define NO_VOLUMETRICS
   #undef TEMP_SENSOR_0
   #undef TEMP_SENSOR_1

Marlin/src/inc/SanityCheck.h

@@ -1555,7 +1555,7 @@ static_assert(Y_MAX_LENGTH >= Y_BED_SIZE, "Movement bounds (Y_MIN_POS, Y_MAX_POS
 #endif
 
 #if ENABLED(G26_MESH_VALIDATION)
-  #if !EXTRUDERS
+  #if !HAS_EXTRUDERS
     #error "G26_MESH_VALIDATION requires at least one extruder."
   #elif !HAS_MESH
     #error "G26_MESH_VALIDATION requires MESH_BED_LEVELING, AUTO_BED_LEVELING_BILINEAR, or AUTO_BED_LEVELING_UBL."