diff --git a/src/AI-EditDistances-Tests/AIManhattanDistanceTest.class.st b/src/AI-EditDistances-Tests/AIManhattanDistanceTest.class.st
index 60e3ad8..3204605 100644
--- a/src/AI-EditDistances-Tests/AIManhattanDistanceTest.class.st
+++ b/src/AI-EditDistances-Tests/AIManhattanDistanceTest.class.st
@@ -13,3 +13,39 @@ AIManhattanDistanceTest >> testManhattanDistanceTo [
 	
 	self assert: (metric distanceBetween: #( 10 20 10 ) and: #( 10 20 20 ) ) equals: 10
 ]
+
+{ #category : 'tests' }
+AIManhattanDistanceTest >> testEmptyCollections [
+	"Checks that the Manhattan distance between empty collections is 0."
+	
+	| metric |
+	metric := AIManhattanDistance new.
+	self assert: (metric distanceBetween: #() and: #()) equals: 0
+]
+
+{ #category : 'tests' }
+AIManhattanDistanceTest >> testIdenticalCollections [
+	"Checks that the Manhattan distance between identical collections is 0."
+	
+	| metric |
+	metric := AIManhattanDistance new.
+	self assert: (metric distanceBetween: #(1 2 3) and: #(1 2 3)) equals: 0
+]
+
+{ #category : 'tests' }
+AIManhattanDistanceTest >> testNegativeNumbers [
+	"Checks Manhattan distance with negative numbers."
+	
+	| metric |
+	metric := AIManhattanDistance new.
+	self assert: (metric distanceBetween: #(-1 2 -3) and: #(1 -2 3)) equals: 12
+]
+
+{ #category : 'tests' }
+AIManhattanDistanceTest >> testFloatingPointNumbers [
+	"Checks Manhattan distance with floating-point numbers."
+	
+	| metric |
+	metric := AIManhattanDistance new.
+	self assert: (metric distanceBetween: #(1.5 2.5) and: #(0.5 0.5)) equals: 3.0
+]
\ No newline at end of file