diff --git a/.classpath b/.classpath
index fb50116..3e0fb27 100644
--- a/.classpath
+++ b/.classpath
@@ -2,5 +2,6 @@
 <classpath>
 	<classpathentry kind="src" path="src"/>
 	<classpathentry kind="con" path="org.eclipse.jdt.launching.JRE_CONTAINER"/>
+	<classpathentry kind="con" path="org.eclipse.jdt.junit.JUNIT_CONTAINER/4"/>
 	<classpathentry kind="output" path="bin"/>
 </classpath>
diff --git a/src/kernel/Cell.java b/src/kernel/Cell.java
index 6e11457..11e9530 100644
--- a/src/kernel/Cell.java
+++ b/src/kernel/Cell.java
@@ -56,6 +56,7 @@ public class Cell {
     }
 
     public void setFormula(Formula formula) {
+    	
         this.formula = formula;
         this.updateValue();
         this.spread();
diff --git a/src/kernel/exception/CycleFoundedException.java b/src/kernel/exception/CycleFoundedException.java
new file mode 100644
index 0000000..bd1918c
--- /dev/null
+++ b/src/kernel/exception/CycleFoundedException.java
@@ -0,0 +1,5 @@
+package kernel.exception;
+
+public class CycleFoundedException extends Exception {
+
+}
diff --git a/src/kernel/function/Average.java b/src/kernel/function/Average.java
index a3f3527..f504d58 100644
--- a/src/kernel/function/Average.java
+++ b/src/kernel/function/Average.java
@@ -15,6 +15,7 @@ public class Average extends Function {
     }
 
     public Double eval() {
+    	
         OptionalDouble average = this.listCells.stream()
                 .mapToDouble(Cell::getValue)
                 .average();
diff --git a/src/kernel/operation/Addition.java b/src/kernel/operation/Addition.java
index 9b3d175..5e3d7d7 100644
--- a/src/kernel/operation/Addition.java
+++ b/src/kernel/operation/Addition.java
@@ -11,6 +11,7 @@ public class Addition extends BinaryOperation {
     }
 
     public Double eval() {
+    	
         return this.leftCell.getValue() + this.rightCell.getValue();
     }
 }
diff --git a/src/kernel/test/Test.java b/src/kernel/test/Test.java
new file mode 100644
index 0000000..5a4f572
--- /dev/null
+++ b/src/kernel/test/Test.java
@@ -0,0 +1,133 @@
+package kernel.test;
+
+import static org.junit.Assert.*;
+
+import java.util.ArrayList;
+import java.util.List;
+
+import kernel.Cell;
+import kernel.function.Sum;
+import kernel.operation.Addition;
+
+
+public class Test {
+
+	@org.junit.Test
+	public void CreateCellValueTest() {
+		Cell A1= new Cell("A",1,25.);
+		assertEquals(A1.getValue(),25.,0);
+		assertEquals(A1.containFormula(),false);
+		assertEquals(A1.getUsedIn().size(),0);
+		assertEquals(A1.getId(),"A1");
+	}
+
+	
+	@org.junit.Test
+	public void CreateCellBinaryOperationTest() {
+		Cell A1= new Cell("A",1,25.);
+		Cell A2= new Cell("A",2,35.);
+        
+
+		Cell A3= new Cell("A",3,new Addition(A1,A2));
+		
+		assertEquals(A3.getValue(),60.,0);
+		assertEquals(A3.containFormula(),true);
+		assertEquals(A3.getUsedIn().size(),0);
+		assertEquals(A3.getId(),"A3");
+		
+		assertEquals(A3.toString(),"A1 + A2");
+		assertEquals(A1.getUsedIn().size(),1);
+		assertEquals(A2.getUsedIn().size(),1);
+			
+
+	}
+
+	
+	@org.junit.Test
+	public void CreateCellFunctionTest() {
+		Cell A1= new Cell("A",1,25.);
+		Cell A2= new Cell("A",2,35.);
+		Cell A3= new Cell("A",3,new Addition(A1,A2));
+		Cell A5= new Cell("A",5,45.);
+		List<Cell> sumList = new ArrayList<>();
+        sumList.add(A1);
+        sumList.add(A2);
+        sumList.add(A3);
+        sumList.add(A5);
+		Cell A4= new Cell("A",4,new Sum(sumList));
+		
+		assertEquals(A4.getValue(),165.,0);
+		assertEquals(A4.containFormula(),true);
+		assertEquals(A4.getUsedIn().size(),0);
+		
+		
+		assertEquals(A4.toString(),"SOMME(A1,A2,A3,A5)");
+		assertEquals(A4.getDevelopedFormula(),"SOMME(A1,A2,A1 + A2,A5)");
+		assertEquals(A1.getUsedIn().size(),2);
+		assertEquals(A2.getUsedIn().size(),2);
+		assertEquals(A3.getUsedIn().size(),1);
+		assertEquals(A5.getUsedIn().size(),1);
+			
+
+	}
+
+	
+	@org.junit.Test
+	public void ModifyCellValueTest() {
+		Cell A1= new Cell("A",1,25.);
+		Cell A2= new Cell("A",2,35.);
+		Cell A3= new Cell("A",3,new Addition(A1,A2));
+		assertEquals(A1.getValue(),25.,0);
+		assertEquals(A2.getValue(),35.,0);	
+		assertEquals(A3.getValue(),60.,0);	
+		A1.setValue(45.);
+		assertEquals(A1.getValue(),45.,0);	
+		assertEquals(A3.getValue(),80.,0);	
+	
+	}
+
+	@org.junit.Test
+	public void ModifyCellFormulaTest() {
+		Cell A1= new Cell("A",1,25.);
+		Cell A2= new Cell("A",2,35.);
+		Cell A3= new Cell("A",3,new Addition(A1,A2));
+		Cell A5= new Cell("A",5,45.);
+		List<Cell> sumList = new ArrayList<>();
+        sumList.add(A1);
+        sumList.add(A2);
+        sumList.add(A3);
+        sumList.add(A5);
+		Cell A4= new Cell("A",4,new Sum(sumList));
+		
+		assertEquals(A4.getValue(),165.,0);
+		assertEquals(A4.containFormula(),true);
+		assertEquals(A4.getUsedIn().size(),0);
+		
+		assertEquals(A1.containFormula(),false);
+		A1.setFormula(new Addition(A2,A5));
+		assertEquals(A1.containFormula(),true);
+		
+		assertEquals(A1.getValue(),80.,0);
+		assertEquals(A3.getValue(),115.,0);
+		assertEquals(A4.getValue(),275.,0);
+		
+		assertEquals(A1.getUsedIn().size(),2);
+		assertEquals(A2.getUsedIn().size(),2);
+		assertEquals(A3.getUsedIn().size(),1);
+		assertEquals(A5.getUsedIn().size(),1);
+		
+		
+		assertEquals(A1.toString(),"A2 + A5");
+		assertEquals(A4.getDevelopedFormula(),"SOMME(A2 + A5,A2,A1 + A2,A5)");
+		
+		
+		assertEquals(A1.getUsedIn().size(),2);
+		assertEquals(A2.getUsedIn().size(),3);
+		assertEquals(A3.getUsedIn().size(),1);
+		assertEquals(A5.getUsedIn().size(),2);
+			
+
+	}
+	
+	
+}
--
libgit2 0.21.2