Add BeJsonSerializable extensions

Src/FluentAssertions/Json/ObjectAssertionsJsonExtensions.cs

@@ -0,0 +1,103 @@
+#if NET6_0_OR_GREATER
+using System;
+using FluentAssertions.Equivalency;
+using FluentAssertions.Execution;
+using FluentAssertions.Primitives;
+
+namespace FluentAssertions;
+
+/// <summary>
+/// Extension methods on <see cref="ObjectAssertions"/> for JSON functionality.
+/// </summary>
+public static class ObjectAssertionsJsonExtensions
+{
+ /// <summary>
+ /// Asserts that an object can be serialized to and deserialized from JSON and retains the values of all members.
+ /// </summary>
+ /// <param name="because">
+ /// A formatted phrase as is supported by <see cref="string.Format(string,object[])"/> explaining why the assertion
+ /// is needed. If the phrase does not start with the word <i>because</i>, it is prepended automatically.
+ /// </param>
+ /// <param name="becauseArgs">
+ /// Zero or more objects to format using the placeholders in <paramref name="because" />.
+ /// </param>
+ public static AndConstraint<ObjectAssertions> BeJsonSerializable(this ObjectAssertions assertions, string because = "", params object[] becauseArgs)
+ {
+ return BeJsonSerializable<object>(assertions, options => options, because, becauseArgs);
+ }
+
+ /// <summary>
+ /// Asserts that an object can be serialized to and deserialized from JSON and retains the values of all members.
+ /// </summary>
+ /// <param name="because">
+ /// A formatted phrase as is supported by <see cref="string.Format(string,object[])"/> explaining why the assertion
+ /// is needed. If the phrase does not start with the word <i>because</i>, it is prepended automatically.
+ /// </param>
+ /// <param name="becauseArgs">
+ /// Zero or more objects to format using the placeholders in <paramref name="because" />.
+ /// </param>
+ public static AndConstraint<ObjectAssertions> BeJsonSerializable<T>(this ObjectAssertions assertions, string because = "", params object[] becauseArgs)
+ where T : class
+ {
+ return BeJsonSerializable<T>(assertions, options => options, because, becauseArgs);
+ }
+
+ /// <summary>
+ /// Asserts that an object can be serialized to and deserialized from JSON and retains the values of all members.
+ /// </summary>
+ /// <param name="options">
+ /// The equivalency options.
+ /// </param>
+ /// <param name="because">
+ /// A formatted phrase as is supported by <see cref="string.Format(string,object[])"/> explaining why the assertion
+ /// is needed. If the phrase does not start with the word <i>because</i>, it is prepended automatically.
+ /// </param>
+ /// <param name="becauseArgs">
+ /// Zero or more objects to format using the placeholders in <paramref name="because" />.
+ /// </param>
+ public static AndConstraint<ObjectAssertions> BeJsonSerializable<T>(this ObjectAssertions assertions, Func<EquivalencyOptions<T>, EquivalencyOptions<T>> options,
+ string because = "", params object[] becauseArgs)
+ where T : class
+ {
+ Execute.Assertion.ForCondition(assertions.Subject is not null)
+ .BecauseOf(because, becauseArgs)
+ .FailWith("Expected {context:object} to be JSON serializable{reason}, but found is null.");
+
+ if (assertions.Subject is not T typedSubject)
+ {
+ Execute.Assertion
+ .BecauseOf(because, becauseArgs)
+ .FailWith("Expected {context:object} to be JSON serializable{reason}, but {context:object} is not assignable to {0}", typeof(T));
+ typedSubject = default;
+ }
+
+ try
+ {
+ var deserializedObject = CreateCloneUsingJsonSerializer(assertions.Subject);
+
+ var defaultOptions = AssertionOptions.CloneDefaults<T>()
+ .RespectingRuntimeTypes()
+ .IncludingFields()
+ .IncludingProperties();
+
+ ((T)deserializedObject).Should().BeEquivalentTo(typedSubject, options);
+ }
+#pragma warning disable CA1031 // Ignore catching general exception
+ catch (Exception exc)
+#pragma warning restore CA1031 // Ignore catching general exception
+ {
+ Execute.Assertion
+ .BecauseOf(because, becauseArgs)
+ .FailWith("Expected {context:object} to be JSON serializable{reason}, but serializing {0} failed with {1}", assertions.Subject, exc);
+ }
+
+ return new AndConstraint<ObjectAssertions>(assertions);
+ }
+
+ private static object CreateCloneUsingJsonSerializer(object subject)
+ {
+ var serializedObject = System.Text.Json.JsonSerializer.Serialize(subject);
+ return System.Text.Json.JsonSerializer.Deserialize(serializedObject, subject.GetType());
+ }
+}
+#endif

Tests/Approval.Tests/ApprovedApi/FluentAssertions/net6.0.verified.txt

@@ -334,6 +334,14 @@ namespace FluentAssertions
  public static FluentAssertions.AndConstraint<FluentAssertions.Primitives.ObjectAssertions> BeDataContractSerializable<T>(this FluentAssertions.Primitives.ObjectAssertions assertions, System.Func<FluentAssertions.Equivalency.EquivalencyOptions<T>, FluentAssertions.Equivalency.EquivalencyOptions<T>> options, string because = "", params object[] becauseArgs) { }
  public static FluentAssertions.AndConstraint<FluentAssertions.Primitives.ObjectAssertions> BeXmlSerializable(this FluentAssertions.Primitives.ObjectAssertions assertions, string because = "", params object[] becauseArgs) { }
  }
+ public static class ObjectAssertionsJsonExtensions
+ {
+ public static FluentAssertions.AndConstraint<FluentAssertions.Primitives.ObjectAssertions> BeJsonSerializable(this FluentAssertions.Primitives.ObjectAssertions assertions, string because = "", params object[] becauseArgs) { }
+ public static FluentAssertions.AndConstraint<FluentAssertions.Primitives.ObjectAssertions> BeJsonSerializable<T>(this FluentAssertions.Primitives.ObjectAssertions assertions, string because = "", params object[] becauseArgs)
+ where T : class { }
+ public static FluentAssertions.AndConstraint<FluentAssertions.Primitives.ObjectAssertions> BeJsonSerializable<T>(this FluentAssertions.Primitives.ObjectAssertions assertions, System.Func<FluentAssertions.Equivalency.EquivalencyOptions<T>, FluentAssertions.Equivalency.EquivalencyOptions<T>> options, string because = "", params object[] becauseArgs)
+ where T : class { }
+ }
  public abstract class OccurrenceConstraint
  {
  protected OccurrenceConstraint(int expectedCount) { }

Tests/FluentAssertions.Specs/Json/ObjectAssertionsJsonExtensionsSpecs.cs

@@ -0,0 +1,131 @@
+#if NET6_0_OR_GREATER
+using System;
+using Xunit;
+
+namespace FluentAssertions.Specs.Json;
+
+public class ObjectAssertionsJsonExtensionsSpecs
+{
+ public class BeJsonSerializable
+ {
+ [Fact]
+ public void Can_serialize_simple_classes()
+ {
+ // Arrange
+ var target = new SimpleClassWithPrimitiveTypes()
+ {
+ Id = 1,
+ GlobalId = Guid.NewGuid(),
+ Name = "foo",
+ DateOfBirth = DateTime.UtcNow,
+ Height = 0.1M,
+ Weight = 0.2,
+ ShoeSize = 42.0F,
+ IsActive = true,
+ Image = [0x20, 0x21, 0x22, 0x23, 0x24, 0x25, 0x26],
+ Category = 'c'
+ };
+
+ // Act / Assert
+ target.Should().BeJsonSerializable();
+ }
+
+ [Fact]
+ public void Can_serialize_nested_classes()
+ {
+ // Arrange
+ var target = new ClassWithNestedClasses
+ {
+ Id = 1,
+ Address = new AddressDto
+ {
+ AddressLine = "foo"
+ },
+ Employment = new EmploymentDto
+ {
+ JobTitle = "foo",
+ PhoneNumber = "bar"
+ }
+ };
+
+ // Act / Assert
+ target.Should().BeJsonSerializable();
+ }
+
+ [Fact]
+ public void Cannot_serialize_classes_without_default_constructor()
+ {
+ // Arrange
+ const string reasonText = "this is the reason";
+ var target = new ClassWithoutDefaultConstructor(10);
+
+ // Act
+ Action act = () => target.Should().BeJsonSerializable(reasonText);
+
+ // Assert
+ act.Should().Throw<Xunit.Sdk.XunitException>()
+ .Which.Message.Should()
+ .Contain("to be JSON serializable")
+ .And.Contain(reasonText)
+ .And.Contain("but serializing")
+ .And.Contain("failed with");
+ }
+ }
+
+ private class SimpleClassWithPrimitiveTypes
+ {
+ public int Id { get; set; }
+
+ public Guid GlobalId { get; set; }
+
+ public string Name { get; set; }
+
+ public DateTime DateOfBirth { get; set; }
+
+ public decimal Height { get; set; }
+
+ public double Weight { get; set; }
+
+ public float ShoeSize { get; set; }
+
+ public bool IsActive { get; set; }
+
+#pragma warning disable CA1819 // Properties should not return arrays
+ public byte[] Image { get; set; }
+#pragma warning restore CA1819 // Properties should not return arrays
+
+ public char Category { get; set; }
+ }
+
+ private class ClassWithoutDefaultConstructor
+ {
+ public int Id { get; }
+
+ public ClassWithoutDefaultConstructor(int value)
+ {
+ Id = value;
+ }
+ }
+
+ private class ClassWithNestedClasses
+ {
+ public int Id { get; set; }
+
+ public AddressDto Address { get; set; }
+
+ public EmploymentDto Employment { get; set; }
+ }
+
+ private class AddressDto
+ {
+ public string AddressLine { get; set; }
+ }
+
+ private class EmploymentDto
+ {
+ public string JobTitle { get; set; }
+
+ public string PhoneNumber { get; set; }
+ }
+}
+#endif