public void AddPackages_Adds_New_Depedenency() { string initialJson = @"{ ""dependencies"": { ""Newtonsoft.Json"": ""5.0.8"", ""Microsoft.Net.Runtime.Interfaces"": """" } }"; string expectedJson = @"{ ""dependencies"": { ""Newtonsoft.Json"": ""5.0.8"", ""Microsoft.Net.Runtime.Interfaces"": """", ""Microsoft.Net.Runtime"": ""1.0.0"" } }"; _mockFileSystem.WriteAllText(_projectJsonPath, initialJson); _packageInstaller.AddPackages(new[] { new PackageMetadata() { Name = "Microsoft.Net.Runtime", Version = "1.0.0" } }); var actualJson = _mockFileSystem.ReadAllText(_projectJsonPath); Assert.Equal(expectedJson, actualJson); }