adding a method as an alternative to bestNodeFor and tests for it

src/AST-Core-Tests/RBMethodNodeTest.class.st

@@ -57,6 +57,54 @@ RBMethodNodeTest >> testCommentedMethodHasComments [
 
 ]
 
+{ #category : #tests }
+RBMethodNodeTest >> testNodeForOffsetAssignment [
+	"test the case of a Assignment"
+	| source ast foundNode |
+	source := 'method Object := Class'.
+	ast := RBParser parseMethod: source.
+	foundNode := ast nodeForOffset: 9.
+	self assert: (foundNode class == RBVariableNode).
+	foundNode := ast nodeForOffset: 14.
+	self assert: (foundNode class == RBAssignmentNode).
+	foundNode := ast nodeForOffset: 19.
+	self assert: (foundNode class == RBVariableNode)
+]
+
+{ #category : #tests }
+RBMethodNodeTest >> testNodeForOffsetMessage [
+	"test the case of Messages"
+	| source ast foundNode |
+	source := 'method Object doit: Class'.
+	ast := RBParser parseMethod: source.
+	foundNode := ast nodeForOffset: 9.
+	self assert: (foundNode class == RBVariableNode).
+	foundNode := ast nodeForOffset: 14.
+	self assert: (foundNode class == RBMessageNode).
+	foundNode := ast nodeForOffset: 22.
+	self assert: (foundNode class == RBVariableNode)
+]
+
+{ #category : #tests }
+RBMethodNodeTest >> testNodeForOffsetTempDefinition [
+	"test the case of Messages"
+	| source ast foundNode |
+	source := 'method | temp |'.
+	ast := RBParser parseFaultyMethod: source.
+	foundNode := ast nodeForOffset: 12.
+	self assert: (foundNode class == RBVariableNode).
+]
+
+{ #category : #tests }
+RBMethodNodeTest >> testNodeForOffsetVar [
+	"test the case of a variable"
+	| source ast foundNode |
+	source := 'method Object'.
+	ast := RBParser parseMethod: source.
+	foundNode := ast nodeForOffset: 9.
+	self assert: (foundNode class == RBVariableNode)
+]
+
 { #category : #tests }
 RBMethodNodeTest >> testSelectorAndArgumentNames [
 

src/AST-Core/RBProgramNode.class.st

@@ -633,6 +633,17 @@ RBProgramNode >> newSource [
 	^self formattedCode
 ]
 
+{ #category : #'node access' }
+RBProgramNode >> nodeForOffset: anInteger [
+	| children |
+	"choosing the best node on the specific offset"
+	children := self children.
+	"when we are on a leaf, we take the leaf node"
+	(children isEmpty) ifTrue: [ (self sourceInterval includes: anInteger) ifTrue: [^self]].
+	"if the node has children then we check the children"
+	children do: [:each | (each sourceInterval includes: anInteger) ifTrue: [^each nodeForOffset: anInteger] ].
+]
+
 { #category : #iterating }
 RBProgramNode >> nodesDo: aBlock [ 
 	aBlock value: self.