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DEdge.Diffract 0.5.0

Diffract is a .NET library that displays a readable diff between two objects. It is particularly useful for unit testing complex objects. Diffract is maintained by folks at D-EDGE.Here is an example:```csharp using DEdge.Diffract;

record User(string Name, int Age, string[] Pets);

var expected = new User("Emma", 42, new[] { "Oscar", "Fluffy", "Tibbles" }); var actual = new User("Andy", 42, new[] { "Oscar", "Sparky" });

Differ.Assert(expected, actual); ```The above throws an AssertionFailedException with the following message: Value differs by 2 fields: Name Expect = "Emma" Actual = "Andy" Pets collection differs: Pets.Count Expect = 3 Actual = 2 Pets[1] Expect = "Fluffy" Actual = "Sparky"Diffract can drill down many composite types:* POCOs;

• C# records;
• F# records and anonymous records;
• F# unions;
• enumerables (IEnumerable<T>);
• dictionaries (IDictionary<K, V>, IReadOnlyDictionary<K, V>);
• value and reference tuples.Values of any other equatable type (like string and int in the above example) are treated as leaves that can be tested for equality.## Example outputsPOCO or record with multiple field differences:```csharp record User(string Name, int Age, bool IsActive);

var expected = new User("Emma", 42, true); var actual = new User("Andy", 35, true);Value differs by 2 fields: Name Expect = "Emma" Actual = "Andy" Age Expect = 42 Actual = 35 F# union where the case is different:fsharp type Contact = | Email of address: string | Phone of number: string

let expected = Email "user@example.com" let actual = Phone "555-123-456"Value differs by union case: Expect is Email Actual is Phone F# union where the case is the same and the value is different:fsharp type Contact = | Email of address: string | Phone of number: string

let expected = Email "user@example.com" let actual = Email "someone@example.com"Value differs by union case Email fields: address Expect = "user@example.com" Actual = "someone@example.com" Enumerables show the counts if they differ, followed by the diffs per item:csharp var expected = new string[] { "first", "second" }; var actual = new string[] { "first", "2nd", "third" };Value collection differs: Count Expect = 2 Actual = 3 [1] Expect = "second" Actual = "2nd" Dictionaries show the keys missing on either side, followed by the diffs per item that exists in both:csharp var expected = new Dictionary<string, int> { { "first", 1 }, { "second", 2 }, { "third", 3 }, }; var actual = new Dictionary<string, int> { { "first", 1 }, { "third", 2 }, { "fourth", 4 }, };Value dictionary differs: ["second"] Actual is missing ["fourth"] Expect is missing ["third"] Expect = 3 Actual = 2 ## APIDiffract lives in the namespace `DEdge.Diffract`. Its main API is the class `Differ`, which provides the following methods:csharp void Assert<T>(T expected, T actual, IDiffer<T> differ = null, PrintParams param = null) Computes the diff between two objects and, if it is not empty, throws an `AssertionFailedException` with the diff as message.csharp string ToString<T>(T expected, T actual, IDiffer<T> differ = null, PrintParams param = null) Prints the diff between two objects to a string.csharp void Write<T>(T expected, T actual, TextWriter writer = null, IDiffer<T> differ = null, PrintParams param = null) Prints the diff between two objects to the given TextWriter (or to standard output if not provided).csharp FSharpOption<Diff> Diff<T>(T expected, T actual, IDiffer<T> differ = null) ```Computes the diff between two objects. Returns None if the objects are found to be equal.