Fix cursor enter/leave attributes in the text editor

src/Album-Tests/AlbTextEditorTest.class.st

@@ -10,12 +10,102 @@ Class {
 	#category : #'Album-Tests-TextEditor'
 }
 
+{ #category : #'tests - cursor attributes' }
+AlbTextEditorTest >> addCursorAttributeLoggingIn: aCollection to: aText [
+	"Add to the 13 to 23 part of aText a cursor attribute that logs in aCollection when the cursor enters and leaves it"
+
+	(aText from: 13 to: 23)
+		onCursorEnter: [ :anEditor :anEvent :aFrom :aTo | aCollection add: #enter -> (aFrom to: aTo) ]
+		leave: [ :anEditor :anEvent :aFrom :aTo | aCollection add: #leave -> (aFrom to: aTo) ]
+]
+
+{ #category : #'tests - cursor attributes' }
+AlbTextEditorTest >> editorTextWithCursorAttributeLoggingIn: aCollection [
+	"Give the editor a text with a cursor attribute logging in aCollection, and forget the initial leave sent when the text is set"
+
+	textEditor text: (self textWithCursorAttributeLoggingIn: aCollection).
+	aCollection removeAll
+]
+
 { #category : #initialization }
 AlbTextEditorTest >> setUp [
 
 	textEditor := AlbTextEditor new
 ]
 
+{ #category : #'tests - cursor attributes' }
+AlbTextEditorTest >> testCursorAttributeAddedToEditorTextFiresEnterAction [
+
+	| log |
+	log := OrderedCollection new.
+	textEditor text: 'Hello World- click here' asRopedText.
+	self addCursorAttributeLoggingIn: log to: textEditor text.
+	textEditor moveCursorTo: 15.
+	self assert: log asArray equals: { (#enter -> (13 to: 23)) }
+]
+
+{ #category : #'tests - cursor attributes' }
+AlbTextEditorTest >> testCursorAttributeDoesNotFireWhenCursorStaysOutside [
+
+	| log |
+	log := OrderedCollection new.
+	self editorTextWithCursorAttributeLoggingIn: log.
+	textEditor moveCursorTo: 2.
+	textEditor moveCursorTo: 5.
+	self assert: log isEmpty
+]
+
+{ #category : #'tests - cursor attributes' }
+AlbTextEditorTest >> testCursorAttributeFiresEnterActionOnceWhileCursorStaysInside [
+
+	| log |
+	log := OrderedCollection new.
+	self editorTextWithCursorAttributeLoggingIn: log.
+	textEditor moveCursorTo: 15.
+	textEditor moveCursorTo: 18.
+	self assert: log asArray equals: { (#enter -> (13 to: 23)) }
+]
+
+{ #category : #'tests - cursor attributes' }
+AlbTextEditorTest >> testCursorAttributeInInitialTextFiresEnterAction [
+
+	| log |
+	log := OrderedCollection new.
+	self editorTextWithCursorAttributeLoggingIn: log.
+	textEditor moveCursorTo: 15.
+	self assert: log asArray equals: { (#enter -> (13 to: 23)) }
+]
+
+{ #category : #'tests - cursor attributes' }
+AlbTextEditorTest >> testCursorAttributeInInitialTextFiresLeaveAction [
+
+	| log |
+	log := OrderedCollection new.
+	self editorTextWithCursorAttributeLoggingIn: log.
+	textEditor moveCursorTo: 15.
+	textEditor moveCursorTo: 2.
+	self assert: log asArray equals: {
+			(#enter -> (13 to: 23)).
+			(#leave -> (13 to: 23)) }
+]
+
+{ #category : #'tests - cursor attributes' }
+AlbTextEditorTest >> testSettingTextFiresLeaveActionOfCursorAttribute [
+
+	| log |
+	log := OrderedCollection new.
+	textEditor text: (self textWithCursorAttributeLoggingIn: log).
+	self assert: log asArray equals: { (#leave -> (13 to: 23)) }
+]
+
+{ #category : #'tests - cursor attributes' }
+AlbTextEditorTest >> testTextWithoutCursorAttributeHasNoEventHandlerAttribute [
+
+	textEditor text: (self textWithCursorAttributeLoggingIn: OrderedCollection new).
+	textEditor text: 'Hello' asRopedText.
+	self deny: textEditor hasEventHandlerAttribute
+]
+
 { #category : #tests }
 AlbTextEditorTest >> test_emptyEditor [
 
@@ -83,3 +173,13 @@ AlbTextEditorTest >> test_textFromStringWithNonPrintableCharacter [
 	"non printable character test"
 	self should: [textEditor checkAndSetText: Character backspace asString] raise: Error.
 ]
+
+{ #category : #'tests - cursor attributes' }
+AlbTextEditorTest >> textWithCursorAttributeLoggingIn: aCollection [
+	"Return the text 'Hello World- click here' whose 'click here' part (13 to 23) logs in aCollection when the cursor enters and leaves it"
+
+	| text |
+	text := 'Hello World- click here' asRopedText.
+	self addCursorAttributeLoggingIn: aCollection to: text.
+	^ text
+]

src/Album/AlbTextCrappyEventHandlerAttribute.class.st

@@ -29,6 +29,13 @@ AlbTextCrappyEventHandlerAttribute >> mayHaveExternalReferences [
 	^ true
 ]
 
+{ #category : #registration }
+AlbTextCrappyEventHandlerAttribute >> registerInEditor: aTextEditor [
+	"Called by aTextEditor when I am part of its text. I receive the cursor events directly through #handleEvent:, so I have nothing to hand over"
+
+
+]
+
 { #category : #comparing }
 AlbTextCrappyEventHandlerAttribute >> type [
 	^ self

src/Album/AlbTextEditor.class.st

@@ -447,6 +447,28 @@ AlbTextEditor >> notifyAttributesWithinCursor: aCollectionOfAttributes [
 				(eachAttribute wantsEvent: anEvent) ifTrue: [ eachAttribute handleEvent: anEvent ] ] ]
 ]
 
+{ #category : #'event handler attributes' }
+AlbTextEditor >> notifyCursorAttributesOfCursorPositions [
+	"Send an enter event to each event handler attribute of my text that contains one of my cursors, and a leave event to the others. Cursor attributes ignore repeated enter or leave events"
+
+	| intervals |
+	intervals := IdentityDictionary new.
+	text findAttributesSuchThat: [ :eachAttribute | eachAttribute isEventHandler ] indicesDo: [ :aStart :anEnd :anAttribute |
+			| previous |
+			previous := intervals at: anAttribute ifAbsent: [ aStart to: anEnd ].
+			intervals at: anAttribute put: ((previous first min: aStart) to: (previous last max: anEnd)) ].
+
+	intervals keysAndValuesDo: [ :anAttribute :anInterval |
+			| anEvent |
+			anEvent := (self cursors anySatisfy: [ :eachCursor | eachCursor position between: anInterval first and: anInterval last ])
+				           ifTrue: [ AlbTextCursorAttributeEnterEvent new ]
+				           ifFalse: [ AlbTextCursorAttributeLeaveEvent new ].
+			anEvent
+				textEditor: self;
+				interval: anInterval.
+			(anAttribute wantsEvent: anEvent) ifTrue: [ anAttribute handleEvent: anEvent ] ]
+]
+
 { #category : #'event firing' }
 AlbTextEditor >> notifyDeletedFrom: aFromIndex to: aToIndex [
 	self dispatchEvent: (AlbTextDeletedEvent new
@@ -756,12 +778,21 @@ AlbTextEditor >> redo [
 ]
 
 { #category : #'event handler attributes' }
-AlbTextEditor >> registerEventHandlerAttribute: anEventHandlerattribute from: aFromIndex to: aToIndex [
-	| eventHandlers |
+AlbTextEditor >> registerEventHandlerAttribute: anEventHandlerAttribute from: aFromIndex to: aToIndex [
+	"Remember that my text has event handler attributes, so that cursor moves notify them, and let the attribute register itself"
+
 	hasEventHandlerAttribute := true.
-	eventHandlers := anEventHandlerattribute eventDispatcher handlers.
-	anEventHandlerattribute  eventDispatcher removeEventHandlers.
-	eventHandlers do: [ :eachHandler | self addEventHandler: (BlEventForwarder forwardTo: eachHandler from: anEventHandlerattribute) ]	
+	anEventHandlerAttribute registerInEditor: self
+]
+
+{ #category : #'event handler attributes' }
+AlbTextEditor >> registerEventHandlerAttributesOfText [
+	"Register the event handler attributes already present in my text, so that they are notified as if they had been added after the text was set"
+
+	hasEventHandlerAttribute := false.
+	text
+		findAttributesSuchThat: [ :eachAttribute | eachAttribute isEventHandler ]
+		indicesDo: [ :aStart :anEnd :anAttribute | self registerEventHandlerAttribute: anAttribute from: aStart to: anEnd ]
 ]
 
 { #category : #'api - shortcuts' }
@@ -800,20 +831,19 @@ AlbTextEditor >> restoreState: aTextEditorMemento [
 
 { #category : #accessing }
 AlbTextEditor >> restoreText: aText [
-
 	"before changing the text we must unsubscribe from existing one"
+
 	text ifNotNil: [ text unsubscribe: self ].
 	self history setUpToStart.
 	cursor := self defaultCursor.
 	secondaryCursors := OrderedCollection new.
 	text := aText.
 	" then subscribe to internal text state change (insertion/deletion/attribute change) "
 	self initializeText: text.
+	self registerEventHandlerAttributesOfText.
 	"Replacing text instance means that we can not guarantee structural integrity
 	of existing cache and have to rebuild it invalidating the whole underlying model structure"
-	segmentCollector
-		ifNil: [ segmentCollector := self newSegmentCollector ]
-		ifNotNil: [ segmentCollector resetCache ].
+	segmentCollector ifNil: [ segmentCollector := self newSegmentCollector ] ifNotNil: [ segmentCollector resetCache ].
 	segmentCollector text: text.
 	self onTextReplaced.
 	"notify UI about structural update"

src/Album/AlbTextEditorCursorAddCommand.class.st

@@ -42,61 +42,8 @@ AlbTextEditorCursorAddCommand >> newHolderEvent [
 
 { #category : #executing }
 AlbTextEditorCursorAddCommand >> processAttributesOn: aTextEditor [
+	"Tell the event handler attributes of the text whether the cursors now enter or leave them"
 
-	| anEditorText thePotentialHandlerTextInterval theEventHandlingAttributes eventHandlingAttributesOutside eventHandlingAttributesInside |
-	self flag: 'what a crap!'.
 	aTextEditor hasEventHandlerAttribute ifFalse: [ ^ self ].
-	anEditorText := aTextEditor text.
-	self cursor position > anEditorText size ifTrue: [ ^ self ].
-	self cursor position <= 0 ifTrue: [ ^ self ].
-
-	"only chars to the left from the cursor handle cursor events"
-	thePotentialHandlerTextInterval := self cursor position to: self cursor position.
-
-	theEventHandlingAttributes := ((thePotentialHandlerTextInterval
-		flatCollect: [ :eachTextIndex | anEditorText attributesAt: eachTextIndex ])
-			select: [ :eachAttribute | eachAttribute isEventHandler ]) asSet.
-
-	theEventHandlingAttributes
-		ifEmpty: [ ^ self ].
-
-	eventHandlingAttributesOutside := OrderedCollection new.
-	eventHandlingAttributesInside := OrderedCollection new.
-
-	anEditorText
-		findAttributes: theEventHandlingAttributes
-		indicesDo: [ :eachEventHandlerStart :eachEventHandlerEnd :eachEventHandlerAttribute |
-			(aTextEditor cursor position between: eachEventHandlerStart and: eachEventHandlerEnd)
-				ifTrue: [
-					eventHandlingAttributesInside
-						add: eachEventHandlerAttribute ->
-							(eachEventHandlerStart to: eachEventHandlerEnd) ]
-				ifFalse: [
-					eventHandlingAttributesOutside
-						add: eachEventHandlerAttribute ->
-							(eachEventHandlerStart to: eachEventHandlerEnd) ] ].
-
-	eventHandlingAttributesOutside do: [ :eachEventHandlerAttributeAndInterval |
-		| eachAttribute eachInterval anEvent |
-		eachAttribute := eachEventHandlerAttributeAndInterval key.
-		eachInterval := eachEventHandlerAttributeAndInterval value.
-		anEvent :=
-			AlbTextCursorAttributeLeaveEvent new
-				textEditor: aTextEditor;
-				interval: eachInterval;
-				yourself.
-		(eachAttribute wantsEvent: anEvent) ifTrue: [
-			eachAttribute handleEvent: anEvent ] ].
-
-	eventHandlingAttributesInside do: [ :eachEventHandlerAttributeAndInterval |
-		| eachAttribute eachInterval anEvent |
-		eachAttribute := eachEventHandlerAttributeAndInterval key.
-		eachInterval := eachEventHandlerAttributeAndInterval value.
-		anEvent :=
-			AlbTextCursorAttributeEnterEvent new
-				textEditor: aTextEditor;
-				interval: eachInterval;
-				yourself.
-		(eachAttribute wantsEvent: anEvent) ifTrue: [
-			eachAttribute handleEvent: anEvent ] ]
+	aTextEditor notifyCursorAttributesOfCursorPositions
 ]

src/Album/AlbTextEventHandlerAttribute.class.st

@@ -38,6 +38,16 @@ AlbTextEventHandlerAttribute >> isEventHandler [
 	^ true
 ]
 
+{ #category : #registration }
+AlbTextEventHandlerAttribute >> registerInEditor: aTextEditor [
+	"Called by aTextEditor when I am part of its text. Move my event handlers to aTextEditor so that the events it receives are forwarded to them"
+
+	| eventHandlers |
+	eventHandlers := self eventDispatcher handlers.
+	self eventDispatcher removeEventHandlers.
+	eventHandlers do: [ :eachHandler | aTextEditor addEventHandler: (BlEventForwarder forwardTo: eachHandler from: self) ]
+]
+
 { #category : #'api - event managing' }
 AlbTextEventHandlerAttribute >> wantsEvent: aBlEvent [