12-Add-simplification-for-ifEmptyifNotEmpty

resources/doc/documentation.md

@@ -132,7 +132,7 @@ Channel do multiple cleanings in protocols.
 *Warnings:*
 This cleaning should not have any counter indication.
 
-### Conditional simplifications
+### Nil conditional simplifications
 
 Chanel simplifies conditionals. For example it will rewrite:
 
@@ -181,6 +181,55 @@ ifNotNil: aBlock
 *Warnings:*
 The only danger of this cleaning happens for projects working on multiple Smalltalks
 
+### Empty conditional simplifications
+
+Chanel simplifies empty conditionals. For example it will rewrite:
+
+| Original | Transformation |
+| ------------- | ------------- |
+| `x isEmpty ifTrue: y` | `x ifEmpty: y` |
+| `x isEmpty ifFalse: y` | `x ifNotEmpty: y` |
+| `x isEmpty ifTrue: y ifFalse: z` | `x ifEmpty: y ifNotEmpty: z` |
+| `x isEmpty ifFalse: y ifTrue: z` | `x ifEmpty: z ifNotEmpty: y` |
+| `x isNotEmpty ifTrue: y` | `x ifNotEmpty: y` |
+| `x isNotEmpty ifFalse: y` | `x ifEmpty: y` |
+| `x isNotEmpty ifTrue: y ifFalse: z` | `x ifEmpty: z ifNotEmpty: y` |
+| `x isNotEmpty ifFalse: y ifTrue: z` | `x ifEmpty: y ifNotEmpty: z` |
+| `x ifEmpty: [ true ] ifNotEmpty: [ false ]` | `x isEmpty` |
+| `x ifEmpty: [ false ] ifNotEmpty: [ true ]` | `x isNotEmpty` |
+| `x ifNotEmpty: [ false ] ifEmpty: [ true ]` | `x isEmpty` |
+| `x ifNotEmpty: [ true ] ifEmpty: [ false ]` | `x isNotEmpty` |
+| `x isEmpty ifTrue: [ true ] ifFalse: [ false ]` | `x isEmpty` |
+| `x isEmpty ifTrue: [ false ] ifFalse: [ true ]` | `x isNotEmpty` |
+| `x isEmpty ifFalse: [ false ] ifTrue: [ true ]` | `x isEmpty` |
+| `x isEmpty ifFalse: [ true ] ifTrue: [ false ]` | `x isNotEmpty` |
+| `x isNotEmpty ifTrue: [ true ] ifFalse: [ false ]` | `x isNotEmpty` |
+| `x isNotEmpty ifTrue: [ false ] ifFalse: [ true ]` | `x isEmpty` |
+| `x isNotEmpty ifFalse: [ false ] ifTrue: [ true ]` | `x isNotEmpty` |
+| `x isNotEmpty ifFalse: [ true ] ifTrue: [ false ]` | `x isEmpty` |
+
+*Conditions for the cleanings to by applied:*
+- Can be applied on any classes and traits.
+- A pattern from the list above match.
+- Does not apply if the application of the pattern would cause an infinit loop. For example it will **not** rewrite:
+
+```Smalltalk
+ifEmpty:: aBlock
+	^ self isEmpty ifTrue: aBlock
+```
+
+into:
+
+```Smalltalk
+ifEmpty: aBlock
+	^ self ifEmpty: aBlock
+```
+
+*Warnings:*
+This cleaner might introduce problems in two cases:
+- You project works on multiple smalltalks with different APIs
+- You have your own objects implementing #isEmpty or #isNotEmpty but not the conditionals. 
+
 ### Methods with alias unification
 
 Chanel unify the use of some methods with alias. Here is the list of rewrites:

src/Chanel-Tests/ChanelEmptyConditionalSimplifierCleanerTest.class.st

@@ -0,0 +1,235 @@
+"
+A ChanelEmptyConditionalSimplifierCleanerTest is a test class for testing the behavior of ChanelEmptyConditionalSimplifierCleaner
+"
+Class {
+	#name : #ChanelEmptyConditionalSimplifierCleanerTest,
+	#superclass : #ChanelAbstractCleanerTest,
+	#category : #'Chanel-Tests'
+}
+
+{ #category : #running }
+ChanelEmptyConditionalSimplifierCleanerTest >> setUp [
+	super setUp.
+	class := self createDefaultClass
+]
+
+{ #category : #tests }
+ChanelEmptyConditionalSimplifierCleanerTest >> testDoesNotReplaceIfItIntroduceAnInfinitLoop [
+	| oldMethod |
+	class
+		compile:
+			'ifEmpty: aBlock
+  ^self isEmpty ifTrue: aBlock'.
+
+	oldMethod := class >> #ifEmpty:.
+
+	self runCleaner.
+
+	self
+		assert: (class >> #ifEmpty:) sourceCode
+		equals:
+			'ifEmpty: aBlock
+  ^self isEmpty ifTrue: aBlock'.
+
+	self assert: class >> #ifEmpty: identicalTo: oldMethod
+]
+
+{ #category : #tests }
+ChanelEmptyConditionalSimplifierCleanerTest >> testDoesNotReplaceIfItIntroduceAnInfinitLoop2 [
+	| oldMethod |
+	class
+		compile:
+			'ifEmpty: aBlock
+  self isEmpty ifTrue: aBlock'.
+
+	oldMethod := class >> #ifEmpty:.
+
+	self runCleaner.
+
+	self
+		assert: (class >> #ifEmpty:) sourceCode
+		equals:
+			'ifEmpty: aBlock
+  self isEmpty ifTrue: aBlock'.
+
+	self assert: class >> #ifEmpty: identicalTo: oldMethod
+]
+
+{ #category : #tests }
+ChanelEmptyConditionalSimplifierCleanerTest >> testIfEmptyIfNotEmpty [
+	self assert: '#() ifEmpty: [ true ] ifNotEmpty: [ false ]' isRewrittenAs: '#() isEmpty'
+]
+
+{ #category : #tests }
+ChanelEmptyConditionalSimplifierCleanerTest >> testIfEmptyIfNotEmpty2 [
+	self assert: '#() ifEmpty: [ false ] ifNotEmpty: [ true ]' isRewrittenAs: '#() isNotEmpty'
+]
+
+{ #category : #tests }
+ChanelEmptyConditionalSimplifierCleanerTest >> testIfNotEmptyIfEmpty [
+	self assert: '#() ifNotEmpty: [ false ] ifEmpty: [ true ]' isRewrittenAs: '#() isEmpty'
+]
+
+{ #category : #tests }
+ChanelEmptyConditionalSimplifierCleanerTest >> testIfNotEmptyIfEmpty2 [
+	self assert: '#() ifNotEmpty: [ true ] ifEmpty: [ false ]' isRewrittenAs: '#() isNotEmpty'
+]
+
+{ #category : #tests }
+ChanelEmptyConditionalSimplifierCleanerTest >> testIsEmptyIfFalse [
+	self assert: '#() isEmpty ifFalse: [ 2 ]' isRewrittenAs: '#() ifNotEmpty: [ 2 ]'
+]
+
+{ #category : #tests }
+ChanelEmptyConditionalSimplifierCleanerTest >> testIsEmptyIfFalseIfTrue [
+	self assert: '#() isEmpty ifFalse: [ 2 ] ifTrue: [ 1 ]' isRewrittenAs: '#() ifEmpty: [ 1 ] ifNotEmpty: [ 2 ]'
+]
+
+{ #category : #tests }
+ChanelEmptyConditionalSimplifierCleanerTest >> testIsEmptyIfFalseIfTrue2 [
+	self assert: '#() isEmpty ifFalse: [ false ] ifTrue: [ true ]' isRewrittenAs: '#() isEmpty'
+]
+
+{ #category : #tests }
+ChanelEmptyConditionalSimplifierCleanerTest >> testIsEmptyIfFalseIfTrue3 [
+	self assert: '#() isEmpty ifFalse: [ true ] ifTrue: [ false ]' isRewrittenAs: '#() isNotEmpty'
+]
+
+{ #category : #tests }
+ChanelEmptyConditionalSimplifierCleanerTest >> testIsEmptyIfTrue [
+	self assert: '#() isEmpty ifTrue: [ 2 ]' isRewrittenAs: '#() ifEmpty: [ 2 ]'
+]
+
+{ #category : #tests }
+ChanelEmptyConditionalSimplifierCleanerTest >> testIsEmptyIfTrueIfFalse [
+	self assert: '#() isEmpty ifTrue: [ 1 ] ifFalse: [ 2 ]' isRewrittenAs: '#() ifEmpty: [ 1 ] ifNotEmpty: [ 2 ]'
+]
+
+{ #category : #tests }
+ChanelEmptyConditionalSimplifierCleanerTest >> testIsEmptyIfTrueIfFalse2 [
+	self assert: '#() isEmpty ifTrue: [ true ] ifFalse: [ false ]' isRewrittenAs: '#() isEmpty'
+]
+
+{ #category : #tests }
+ChanelEmptyConditionalSimplifierCleanerTest >> testIsEmptyIfTrueIfFalse3 [
+	self assert: '#() isEmpty ifTrue: [ false ] ifFalse: [ true ]' isRewrittenAs: '#() isNotEmpty'
+]
+
+{ #category : #tests }
+ChanelEmptyConditionalSimplifierCleanerTest >> testIsNotEmptyIfFalse [
+	self assert: '#() isNotEmpty ifFalse: [ 2 ]' isRewrittenAs: '#() ifEmpty: [ 2 ]'
+]
+
+{ #category : #tests }
+ChanelEmptyConditionalSimplifierCleanerTest >> testIsNotEmptyIfFalseIfTrue [
+	self assert: '#() isNotEmpty ifFalse: [ 1 ] ifTrue: [ 2 ]' isRewrittenAs: '#() ifEmpty: [ 1 ] ifNotEmpty: [ 2 ]'
+]
+
+{ #category : #tests }
+ChanelEmptyConditionalSimplifierCleanerTest >> testIsNotEmptyIfFalseIfTrue2 [
+	self assert: '#() isNotEmpty ifFalse: [ true ] ifTrue: [ false ]' isRewrittenAs: '#() isEmpty'
+]
+
+{ #category : #tests }
+ChanelEmptyConditionalSimplifierCleanerTest >> testIsNotEmptyIfFalseIfTrue3 [
+	self assert: '#() isNotEmpty ifFalse: [ false ] ifTrue: [ true ]' isRewrittenAs: '#() isNotEmpty'
+]
+
+{ #category : #tests }
+ChanelEmptyConditionalSimplifierCleanerTest >> testIsNotEmptyIfTrue [
+	self assert: '#() isNotEmpty ifTrue: [ 2 ]' isRewrittenAs: '#() ifNotEmpty: [ 2 ]'
+]
+
+{ #category : #tests }
+ChanelEmptyConditionalSimplifierCleanerTest >> testIsNotEmptyIfTrueIfFalse [
+	self assert: '#() isNotEmpty ifTrue: [ 2 ] ifFalse: [ 1 ]' isRewrittenAs: '#() ifEmpty: [ 1 ] ifNotEmpty: [ 2 ]'
+]
+
+{ #category : #tests }
+ChanelEmptyConditionalSimplifierCleanerTest >> testIsNotEmptyIfTrueIfFalse2 [
+	self assert: '#() isNotEmpty ifTrue: [ false ] ifFalse: [ true ]' isRewrittenAs: '#() isEmpty'
+]
+
+{ #category : #tests }
+ChanelEmptyConditionalSimplifierCleanerTest >> testIsNotEmptyIfTrueIfFalse3 [
+	self assert: '#() isNotEmpty ifTrue: [ true ] ifFalse: [ false ]' isRewrittenAs: '#() isNotEmpty'
+]
+
+{ #category : #tests }
+ChanelEmptyConditionalSimplifierCleanerTest >> testReplacementDoesNotRemoveExtensions [
+	class
+		compile:
+			('{1}
+  {2}' format: {self selector . '#() isEmpty ifTrue: [ false ]'})
+		classified: self extensionProtocol.
+
+	self runCleaner.
+
+	self
+		assert: (class >> self selector) sourceCode
+		equals:
+			('{1}
+  {2}' format: {self selector . '#() ifEmpty: [ false ]'}).
+
+	self assert: (class >> self selector) protocol equals: self extensionProtocol
+]
+
+{ #category : #tests }
+ChanelEmptyConditionalSimplifierCleanerTest >> testReplacementInTraits [
+	| trait |
+	trait := self createDefaultTrait.
+
+	class setTraitComposition: trait.
+
+	trait
+		compile:
+			('{1}
+  {2}' format: {self selector . '#() isEmpty ifTrue: [ false ]'}).
+
+	self runCleaner.
+
+	self
+		assert: (trait >> self selector) sourceCode
+		equals:
+			('{1}
+  {2}' format: {self selector . '#() ifEmpty: [ false ]'}).
+
+	self assert: (trait localSelectors includes: self selector).
+	self deny: (class localSelectors includes: self selector)
+]
+
+{ #category : #tests }
+ChanelEmptyConditionalSimplifierCleanerTest >> testReplacementOnClassSide [
+	class class
+		compile:
+			('{1}
+  {2}' format: {self selector . '#() isEmpty ifTrue: [ false ]'}).
+
+	self runCleaner.
+
+	self
+		assert: (class class >> self selector) sourceCode
+		equals:
+			('{1}
+  {2}' format: {self selector . '#() ifEmpty: [ false ]'})
+]
+
+{ #category : #tests }
+ChanelEmptyConditionalSimplifierCleanerTest >> testWithNothingToReplace [
+	| oldMethod |
+	class
+		compile:
+			('{1}
+	{2}' format: {self selector . '#() ifEmpty: [ false ]'}).
+
+	oldMethod := class >> self selector.
+	self runCleaner.
+
+	self
+		assert: (class >> self selector) sourceCode
+		equals:
+			('{1}
+	{2}' format: {self selector . '#() ifEmpty: [ false ]'}).
+
+	self assert: class >> self selector identicalTo: oldMethod
+]

src/Chanel/ChanelEmptyConditionalSimplifierCleaner.class.st

@@ -0,0 +1,46 @@
+"
+Description
+--------------------
+
+I am a cleaner simplifying conditionals related to emptyness of collections.
+"
+Class {
+	#name : #ChanelEmptyConditionalSimplifierCleaner,
+	#superclass : #ChanelMethodRewriterCleaner,
+	#category : #Chanel
+}
+
+{ #category : #accessing }
+ChanelEmptyConditionalSimplifierCleaner class >> priority [
+	^ 3500
+]
+
+{ #category : #cleaning }
+ChanelEmptyConditionalSimplifierCleaner >> rewriter [
+	^ RBParseTreeRewriter new
+		replace: '`@receiver ifEmpty: [ true ] ifNotEmpty: [ false ]' with: '`@receiver isEmpty';
+		replace: '`@receiver ifEmpty: [ false ] ifNotEmpty: [ true ]' with: '`@receiver isNotEmpty';
+		replace: '`@receiver ifNotEmpty: [ false ] ifEmpty: [ true ]' with: '`@receiver isEmpty';
+		replace: '`@receiver ifNotEmpty: [ true ] ifEmpty: [ false ]' with: '`@receiver isNotEmpty';
+
+		replace: '`@receiver isEmpty ifTrue: [ true ] ifFalse: [ false ]' with: '`@receiver isEmpty';
+		replace: '`@receiver isEmpty ifTrue: [ false ] ifFalse: [ true ]' with: '`@receiver isNotEmpty';
+		replace: '`@receiver isEmpty ifFalse: [ false ] ifTrue: [ true ]' with: '`@receiver isEmpty';
+		replace: '`@receiver isEmpty ifFalse: [ true ] ifTrue: [ false ]' with: '`@receiver isNotEmpty';
+
+		replace: '`@receiver isNotEmpty ifTrue: [ true ] ifFalse: [ false ]' with: '`@receiver isNotEmpty';
+		replace: '`@receiver isNotEmpty ifTrue: [ false ] ifFalse: [ true ]' with: '`@receiver isEmpty';
+		replace: '`@receiver isNotEmpty ifFalse: [ false ] ifTrue: [ true ]' with: '`@receiver isNotEmpty';
+		replace: '`@receiver isNotEmpty ifFalse: [ true ] ifTrue: [ false ]' with: '`@receiver isEmpty';
+
+		replace: '`@receiver isEmpty ifTrue: `@arg' with: '`@receiver ifEmpty: `@arg';
+		replace: '`@receiver isEmpty ifFalse: `@arg' with: '`@receiver ifNotEmpty: `@arg';
+		replace: '`@receiver isEmpty ifTrue: `@arg ifFalse: `@arg2' with: '`@receiver ifEmpty: `@arg ifNotEmpty: `@arg2';
+		replace: '`@receiver isEmpty ifFalse: `@arg ifTrue: `@arg2' with: '`@receiver ifEmpty: `@arg2 ifNotEmpty: `@arg';
+
+		replace: '`@receiver isNotEmpty ifTrue: `@arg' with: '`@receiver ifNotEmpty: `@arg';
+		replace: '`@receiver isNotEmpty ifFalse: `@arg' with: '`@receiver ifEmpty: `@arg';
+		replace: '`@receiver isNotEmpty ifTrue: `@arg ifFalse: `@arg2' with: '`@receiver ifEmpty: `@arg2 ifNotEmpty: `@arg';
+		replace: '`@receiver isNotEmpty ifFalse: `@arg ifTrue: `@arg2' with: '`@receiver ifEmpty: `@arg ifNotEmpty: `@arg2';
+		yourself
+]