diff --git a/tp1/DbContextLib/LibraryContext.cs b/tp1/DbContextLib/LibraryContext.cs
index 16fd76b..8ef5245 100644
--- a/tp1/DbContextLib/LibraryContext.cs
+++ b/tp1/DbContextLib/LibraryContext.cs
@@ -29,6 +29,40 @@ namespace DbContextLib
             : base(options)
         { }
 
+        public void AddBook(BookEntity book)
+        {
+            if (!BooksSet.Contains(book))
+            {
+                BooksSet.Add(book);
+            }
+        }
+
+        public void AddPerson(PersonEntity person)
+        {
+            if (!PersonSet.Contains(person))
+            {
+                PersonSet.Add(person);
+            }
+        }
+        public void RemoveAll()
+        {
+
+            if (BooksSet.Count() != 0)
+            {
+                foreach (var book in BooksSet)
+                {
+                    BooksSet.Remove(book);
+                }
+            }
+            if (PersonSet.Count() != 0)
+            {
+                foreach (var person in PersonSet)
+                {
+                    PersonSet.Remove(person);
+                }
+            }
+
+        }
 
     }
 }
diff --git a/tp1/UnitTests/UnitTest1.cs b/tp1/UnitTests/UnitTest1.cs
index d775f8c..e3555f9 100644
--- a/tp1/UnitTests/UnitTest1.cs
+++ b/tp1/UnitTests/UnitTest1.cs
@@ -6,6 +6,8 @@ using Microsoft.EntityFrameworkCore;
 using System.Linq;
 using Xunit;
 using Microsoft.Data.Sqlite;
+using System;
+using static System.Reflection.Metadata.BlobBuilder;
 
 namespace UnitTests
 {
@@ -20,27 +22,30 @@ namespace UnitTests
             var options = new DbContextOptionsBuilder<LibraryContext>().UseSqlite().Options;
 
             //prepares the database with one instance of the context
-            using (var context = new StubbedContext(options))
+            //using (var context = new StubbedContext(options))
+            using (var context = new StubbedContext())
             {
-                //context.Database.OpenConnection();
                 context.Database.EnsureCreated();
                 context.PersonSet.Include(pers => pers.Books).ToList();
                 BookEntity the100 = new BookEntity { Title = "the100", Author = "", Isbn = "", Id =3 };
                 BookEntity princeOfPersia = new BookEntity { Title = "princeOfPersia", Author = "", Isbn = "", Id = 4 };
                 BookEntity PercyJackson = new BookEntity { Title = "PercyJackson", Author = "", Isbn = "", Id = 5 };
-                context.BooksSet.Add(the100);
-                context.BooksSet.Add(princeOfPersia);
-                context.BooksSet.Add(PercyJackson);
+                context.AddBook(the100);
+                context.AddBook(princeOfPersia);
+                context.AddBook(PercyJackson);
                 context.SaveChanges();
             }
 
 
             //uses another instance of the context to do the tests
-            using (var context = new StubbedContext(options))
+            //using (var context = new StubbedContext(options))
+            using (var context = new StubbedContext())
             {
                 context.Database.EnsureCreated();
-                Assert.Equal(5, context.BooksSet.Count());
+                Assert.Equal(3, context.BooksSet.Count());
                 Assert.Equal(1, context.BooksSet.Where(b => b.Title.Contains("the100")).Count());
+                context.RemoveAll();
+                context.SaveChanges();
             }
         }
 
@@ -53,25 +58,29 @@ namespace UnitTests
             var options = new DbContextOptionsBuilder<LibraryContext>().UseSqlite().Options;
 
             //prepares the database with one instance of the context
-            using (var context = new StubbedContext(options))
+            //using (var context = new StubbedContext(options))
+            using (var context = new StubbedContext())
             {
                 //context.Database.OpenConnection();
                 context.Database.EnsureCreated();
                 context.PersonSet.Include(pers => pers.Books).ToList();
                 PersonEntity p1 = new PersonEntity { FirstName = "Franc", LastName = "Bertinelli", Id = 2 };
                 PersonEntity p2 = new PersonEntity { FirstName = "Jean", LastName = "Dubois", Id = 3 };
-                context.PersonSet.Add(p1);
-                context.PersonSet.Add(p2);
+                context.AddPerson(p1);
+                context.AddPerson(p2);
                 context.SaveChanges();
             }
 
 
             //uses another instance of the context to do the tests
-            using (var context = new StubbedContext(options))
+            //using (var context = new StubbedContext(options))
+            using (var context = new StubbedContext())
             {
                 context.Database.EnsureCreated();
-                Assert.Equal(3, context.PersonSet.Count());
-                Assert.Equal(1, context.PersonSet.Where(p => p.FirstName.Contains("Granc")).Count());
+                Assert.Equal(2, context.PersonSet.Count());
+                Assert.Equal(1, context.PersonSet.Where(p => p.FirstName.Contains("Jean")).Count());
+                context.RemoveAll();
+                context.SaveChanges();
             }
         }
 
@@ -84,29 +93,32 @@ namespace UnitTests
             var options = new DbContextOptionsBuilder<LibraryContext>().UseSqlite().Options;
 
             //prepares the database with one instance of the context
-            
-            //prepares the database with one instance of the context
-            using (var context = new StubbedContext(options))
-            {
 
+            //using (var context = new StubbedContext(options))
+            using (var context = new StubbedContext())
+            {
+               context.Database.EnsureCreated();
                 context.PersonSet.Include(pers => pers.Books).ToList();
                 BookEntity the100 = new BookEntity { Title = "the100", Author = "", Isbn = "", Id = 3 };
                 BookEntity princeOfPersia = new BookEntity { Title = "princeOfPersia", Author = "", Isbn = "", Id = 4 };
                 BookEntity PercyJackson = new BookEntity { Title = "PercyJackson", Author = "", Isbn = "", Id = 5 };
-                context.BooksSet.Add(the100);
-                context.BooksSet.Add(princeOfPersia);
-                context.BooksSet.Add(PercyJackson);
+                context.AddBook(the100);
+                context.AddBook(princeOfPersia);
+                context.AddBook(PercyJackson);
                 context.SaveChanges();
+              
             }
-
+            
             //prepares the database with one instance of the context
-            using (var context = new StubbedContext(options))
+            //using (var context = new StubbedContext(options))
+            using (var context = new StubbedContext())
             {
+                context.Database.EnsureCreated();
                 context.PersonSet.Include(pers => pers.Books).ToList();
-                string nameToFind = "princeOfPersia";
-                Assert.Equal(2, context.BooksSet.Where(n => n.Title.ToLower().Contains(nameToFind)).Count());
-                var ewok = context.BooksSet.Where(n => n.Title.ToLower().Contains(nameToFind)).First();
-                ewok.Title = "l'Odyssée";
+                var book = context.BooksSet.Where(n => n.Title.Contains("princeOfPersia")).FirstOrDefault();
+                book.Title = "l'Odyssée"; 
+                Assert.Equal("l'Odyssée", book.Title);
+                context.RemoveAll();
                 context.SaveChanges();
             }
         }
@@ -120,25 +132,31 @@ namespace UnitTests
             //prepares the database with one instance of the context
 
             //prepares the database with one instance of the context
-            using (var context = new StubbedContext(options))
+            //using (var context = new StubbedContext(options))
+            using (var context = new StubbedContext())
             {
 
                 context.PersonSet.Include(pers => pers.Books).ToList();
                 PersonEntity p1 = new PersonEntity { FirstName = "Franc", LastName = "Bertinelli", Id = 2 };
                 PersonEntity p2 = new PersonEntity { FirstName = "Jean", LastName = "Dubois", Id = 3 };
-                context.PersonSet.Add(p1);
-                context.PersonSet.Add(p2);
+                context.AddPerson(p1);
+                context.AddPerson(p2);
                 context.SaveChanges();
             }
 
             //prepares the database with one instance of the context
-            using (var context = new StubbedContext(options))
+            //using (var context = new StubbedContext(options))
+            using (var context = new StubbedContext())
             {
                 context.PersonSet.Include(pers => pers.Books).ToList();
                 string nameToFind = "Jean";
-                Assert.Equal(1, context.PersonSet.Where(p => p.FirstName.ToLower().Contains(nameToFind)).Count());
-                var person = context.PersonSet.Where(p => p.FirstName.ToLower().Contains(nameToFind)).First();
+                Assert.Equal(1, context.PersonSet.Where(p => p.FirstName.Contains(nameToFind)).Count());
+                var person = context.PersonSet.Where(p => p.FirstName.Contains(nameToFind)).First();
                 person.FirstName = "Jacques";
+
+                Assert.Equal("Jacques", person.FirstName);
+
+                context.RemoveAll();
                 context.SaveChanges();
             }
         }
@@ -151,17 +169,31 @@ namespace UnitTests
             var options = new DbContextOptionsBuilder<LibraryContext>().UseSqlite().Options;
 
             //prepares the database with one instance of the context
-            using (var context = new StubbedContext(options))
+            //using (var context = new StubbedContext(options))
+            using (var context = new StubbedContext())
+            {
+                PersonEntity p1 = new PersonEntity { FirstName = "Franc", LastName = "Bertinelli", Id = 2 };
+                PersonEntity p2 = new PersonEntity { FirstName = "Jean", LastName = "Dubois", Id = 3 };
+                context.AddPerson(p1);
+                context.AddPerson(p2);
+                context.SaveChanges();
+            }
+            //using (var context = new StubbedContext(options))
+            using (var context = new StubbedContext())
             {
 
                 context.PersonSet.Include(pers => pers.Books).ToList();
-                var nb = context.PersonSet.Count();
-                if (nb > 0)
+                var Persons  = context.PersonSet;
+                if (Persons.Count() != 0)
                 {
-                    context.PersonSet.Remove(context.PersonSet.FirstOrDefault());
+                    foreach (var person in Persons)
+                    {
+                        context.PersonSet.Remove(person);
+                    }
                 }
-
-                Assert.Equal(context.PersonSet.Count(), nb - 1);
+                context.SaveChanges();
+                Assert.Equal( 0, context.PersonSet.Count());
+                context.RemoveAll();
                 context.SaveChanges();
             }
         }
@@ -172,79 +204,132 @@ namespace UnitTests
             var connection = new SqliteConnection("DataSource=:memory:");
             connection.Open();
             var options = new DbContextOptionsBuilder<LibraryContext>().UseSqlite().Options;
-         
-            //prepares the database with one instance of the context
 
             //prepares the database with one instance of the context
-            using (var context = new StubbedContext(options))
+            using (var context = new StubbedContext())
+            {
+                BookEntity the100 = new BookEntity { Title = "the100", Author = "", Isbn = "", Id = 3 };
+                BookEntity princeOfPersia = new BookEntity { Title = "princeOfPersia", Author = "", Isbn = "", Id = 4 };
+                BookEntity PercyJackson = new BookEntity { Title = "PercyJackson", Author = "", Isbn = "", Id = 5 };
+                context.AddBook(the100);
+                context.AddBook(princeOfPersia);
+                context.AddBook(PercyJackson);
+                context.SaveChanges();
+            }
+
+            //using (var context = new StubbedContext(options))
+            using (var context = new StubbedContext())
             {   
                 context.PersonSet.Include(pers => pers.Books).ToList();
-                 var nb = context.BooksSet.Count(); 
-                if (nb > 0)
+                 var Books = context.BooksSet;
+                if (Books.Count() != 0)
                 {
-                    context.BooksSet.Remove(context.BooksSet.FirstOrDefault());
+                    foreach (var book in Books)
+                    {
+                        context.BooksSet.Remove(book);
+                    }
                 }
-                Assert.Equal(context.BooksSet.Count(), nb - 1);
                 context.SaveChanges();
+                Assert.Equal(0, context.BooksSet.Count());
+                context.RemoveAll();
+                context.SaveChanges();
+
             }
         }
 
 
         [Fact]
-        public void Delete_TestEmprunt()
+        public void Update_TestEmprunt()
         {
             var connection = new SqliteConnection("DataSource=:memory:");
             connection.Open();
             var options = new DbContextOptionsBuilder<LibraryContext>().UseSqlite().Options;
 
             //prepares the database with one instance of the context
+            using (var context = new StubbedContext())
+            {
 
-            //prepares the database with one instance of the context
-            using (var context = new StubbedContext(options))
+                context.PersonSet.Include(pers => pers.Books).ToList();
+                PersonEntity p1 = new PersonEntity { FirstName = "Franc", LastName = "Bertinelli", Id = 2 };
+                PersonEntity p2 = new PersonEntity { FirstName = "Jean", LastName = "Dubois", Id = 3 };
+                context.AddPerson(p1);
+                context.AddPerson(p2);
+                BookEntity the100 = new BookEntity { Title = "the100", Author = "", Isbn = "", Id = 3 };
+                BookEntity princeOfPersia = new BookEntity { Title = "princeOfPersia", Author = "", Isbn = "", Id = 4 };
+                BookEntity PercyJackson = new BookEntity { Title = "PercyJackson", Author = "", Isbn = "", Id = 5 };
+                context.AddBook(the100);
+                context.AddBook(princeOfPersia);
+                context.AddBook(PercyJackson);
+                context.SaveChanges();
+
+            }
+
+            //using (var context = new StubbedContext(options))
+            using (var context = new StubbedContext())
             {
                 var books = context.BooksSet;
 
                 context.PersonSet.Include(pers => pers.Books).ToList();
-                var person = context.PersonSet.Where(b => b.FirstName.StartsWith("coco")).First();
-                var testbook = new BookEntity();
+                var person = context.PersonSet.Where(b => b.FirstName.Contains("Jean")).First();
                 foreach (var book in books)
                 {
                     if (book.Owner == null)
                     {
-                        person.Books.Add(book);
-                        testbook = book;
+                        book.Owner = person;
                         break;
                     }
                 }
 
-                Assert.Equal(testbook.Owner, person);
+                context.SaveChanges();
+            }
+
+            using (var context = new StubbedContext())
+            {
+                Assert.NotNull(context.BooksSet.Where(b => b.Owner.FirstName.Contains("Jean")).First());
+                context.RemoveAll();
                 context.SaveChanges();
             }
         }
 
         [Fact]
-        public void Delete_TestRendu()
+        public void Update_TestRendu()
         {
             var connection = new SqliteConnection("DataSource=:memory:");
             connection.Open();
             var options = new DbContextOptionsBuilder<LibraryContext>().UseSqlite().Options;
 
             //prepares the database with one instance of the context
+            using (var context = new StubbedContext())
+            {
 
-            //prepares the database with one instance of the context
-            using (var context = new StubbedContext(options))
+                context.PersonSet.Include(pers => pers.Books).ToList();
+                PersonEntity p1 = new PersonEntity { FirstName = "Franc", LastName = "Bertinelli", Id = 2 };
+                PersonEntity p2 = new PersonEntity { FirstName = "Jean", LastName = "Dubois", Id = 3 };
+                context.AddPerson(p1);
+                context.AddPerson(p2);
+                BookEntity the100 = new BookEntity { Title = "the100", Author = "", Isbn = "", Id = 3 };
+                BookEntity princeOfPersia = new BookEntity { Title = "princeOfPersia", Author = "", Isbn = "", Id = 4 };
+                BookEntity PercyJackson = new BookEntity { Title = "PercyJackson", Author = "", Isbn = "", Id = 5 };
+                context.AddBook(the100);
+                context.AddBook(princeOfPersia);
+                context.AddBook(PercyJackson);
+                context.SaveChanges();
+
+            }
+
+            //using (var context = new StubbedContext(options))
+            using (var context = new StubbedContext())
             {
                 var books = context.BooksSet;
 
                 context.PersonSet.Include(pers => pers.Books).ToList();
-                var person = context.PersonSet.Where(b => b.FirstName.StartsWith("coco")).First();
+                var person = context.PersonSet.Where(b => b.FirstName.StartsWith("Jean")).First();
                 var testbook = new BookEntity();
                 foreach (var book in books)
                 {
                     if (book.Owner == null)
                     {
-                        person.Books.Add(book);
-                        testbook = book;
+                        book.Owner = person;
                         break;
                     }
                 }
@@ -257,7 +342,8 @@ namespace UnitTests
                         book.Owner = null;  
                     }
                 }
-                Assert.Null(testbook.Owner);
+                Assert.Equal(context.BooksSet.Count(), context.BooksSet.Where(b => b.Owner == null).Count());
+                context.RemoveAll();
                 context.SaveChanges();
             }
         }