Fixes: #8332.

src/Kernel-Tests/CommonClassDefinitionPrinterTest.class.st

@@ -6,21 +6,24 @@ Class {
 	#name : #CommonClassDefinitionPrinterTest,
 	#superclass : #TestCase,
 	#instVars : [
-		'slotuse'
+		'slotDisplay',
+		'slotUse'
 	],
 	#category : #'Kernel-Tests-Fluid'
 }
 
 { #category : #running }
 CommonClassDefinitionPrinterTest >> setUp [ 
 	super setUp.
-	slotuse := ClassDefinitionPrinter showFluidClassDefinition.
+	slotUse := ClassDefinitionPrinter showFluidClassDefinition.
+	slotDisplay := ClassDefinitionPrinter displayEmptySlots.
 
 ]
 
 { #category : #running }
 CommonClassDefinitionPrinterTest >> tearDown [
 
-	ClassDefinitionPrinter showFluidClassDefinition: slotuse.
+	ClassDefinitionPrinter showFluidClassDefinition: slotUse.
+	ClassDefinitionPrinter displayEmptySlots: slotDisplay.
 	super tearDown
 ]

src/Kernel-Tests/FluidClassDefinitionPrinterTest.class.st

@@ -99,6 +99,36 @@ FluidClassDefinitionPrinterTest >> testDefinitionWithComplexSlot [
 	package: ''Kernel-Tests''' 
 ]
 
+{ #category : #'tests - unnecessary values' }
+FluidClassDefinitionPrinterTest >> testDisplayEmptySlots [
+	"I would like to be able to test if I provide too many empty values that
+	the default empty values are just ignored."
+	| class |
+	ClassDefinitionPrinter displayEmptySlots: true.
+	class := (Object << #CDFluidMock
+	slots: {};
+	tag: 'BasicObjects';
+	package: 'Kernel') build.
+	self assert: (self forClass: class) equals: 'Object << #CDFluidMock
+	slots: {};
+	package: ''_UnpackagedPackage'''
+
+]
+
+{ #category : #'tests - unnecessary values' }
+FluidClassDefinitionPrinterTest >> testDoesNotDisplayEmptySlots [
+
+	| class |
+	ClassDefinitionPrinter displayEmptySlots: false.
+	class := (Object << #CDFluidMock
+	slots: {};
+	tag: 'BasicObjects';
+	package: 'Kernel') build.
+	self assert: (self forClass: class) equals: 'Object << #CDFluidMock
+	package: ''_UnpackagedPackage'''
+
+]
+
 { #category : #'tests - expanded' }
 FluidClassDefinitionPrinterTest >> testExpandedEmptyLayoutClass [
 

src/Kernel/ClassDefinitionPrinter.class.st

@@ -59,11 +59,24 @@ Class {
 		'forClass'
 	],
 	#classVars : [
+		'DisplayEmptySlots',
 		'ShowFluidClassDefinition'
 	],
 	#category : #'Kernel-ClassDefinitionPrinter'
 }
 
+{ #category : #configure }
+ClassDefinitionPrinter class >> displayEmptySlots [
+
+	^ DisplayEmptySlots ifNil: [ DisplayEmptySlots := false ]
+]
+
+{ #category : #configure }
+ClassDefinitionPrinter class >> displayEmptySlots: aBoolean [
+
+	DisplayEmptySlots := aBoolean
+]
+
 { #category : #'instance creation' }
 ClassDefinitionPrinter class >> fluid [ 
 	^  FluidClassDefinitionPrinter basicNew initialize 
@@ -125,7 +138,20 @@ Object << #Point
 	
 We suggest to use it because it will become the default syntax for Pharo. This new class definition has been designed to control the parameter explosion of the old one. 
 In addition, as soon as you will use slots such as ObservableSlot and more this fluid class definition will be used because the old one is not handling well the slots.';
-		target: self
+		target: self.
+
+	(aBuilder setting: #displayEmptySlots)
+		parent: #codeBrowsing;
+		default: false;
+		label: 'Display empty slots';
+		description: 'If true, the system will display the slots even if they are empty e.g., 
+
+Object << #Faked
+	slots: { };
+	tag: ''BasicObjects'';
+	package: ''Kernel''
+	';
+		target: self.
 ]
 
 { #category : #configure }

src/Kernel/FluidClassDefinitionPrinter.class.st

@@ -46,8 +46,9 @@ FluidClassDefinitionPrinter >> classDefinitionString [
 				ifFalse: [ self layoutOn: s ].
 
 			self traitsOn: s.
-
-		  forClass slots ifNotEmpty: [ self slotsOn: s ].
+			self class displayEmptySlots 
+				ifTrue: [ self slotsOn: s ]
+		  		ifFalse: [forClass slots ifNotEmpty: [ self slotsOn: s ]].
 		  forClass classVariables ifNotEmpty: [ self sharedVariablesOn: s ].
 		  forClass sharedPools ifNotEmpty: [ self sharedPoolsOn: s ].