Pretender

Example

var pretendMyInterface = Pretend.That<IMyInterface>();

pretendMyInterface
    .Setup(i => i.MyMethod(It.IsAny<string>(), 14))
    .Returns("Hello!");

var myInterface = pretendMyInterface.Create();

Benchmarks vs Competitors

Doing a simple Is.IsAny<string>() or equivalent call.

Method	Mean	Error	StdDev	Median	Ratio	RatioSD	Gen0	Gen1	Allocated	Alloc Ratio
MoqTest	45,863.83 ns	897.457 ns	1,641.051 ns	45,172.41 ns	509.57	19.58	1.3428	1.2207	8850 B	22.12
NSubstituteTest	4,151.76 ns	82.517 ns	126.012 ns	4,133.53 ns	45.69	1.68	1.2360	0.0381	7760 B	19.40
PretenderTest	91.08 ns	1.432 ns	1.270 ns	91.33 ns	1.00	0.00	0.0637	-	400 B	1.00

0.1.0

• Intercept .Create calls
• Base implementation name off of ITypeSymbol derived info
• Async/Task Support
• Benchmark vs NSub & Moq
• Property Support
• Compiled Setup calls
• Intercept Setup calls
• Support Base MatcherAttribute
• Special case AnyMatcher
• Multiple uses of single type
• Classes
• Constructor support
• out parameters
• Make our own delegate for matcher calls
• Maybe not even use expressions in Setup
• Use Span<object?> for CallInfo arguments
• Multiple method overloads

0.2.0

• Check how many times a call has been made
• Take constructor args in .Create() call
• Respect [Pretend] attribute that is placed on a partial class
• A lot more benchmarks
• Property setter
• Static Abstract (not support but we should fake an implementation)
• More matchers
• Probably need a static matcher register :(
• Support Matcher arguments and fallback if impossible
• Obsolete public types that exist only for SourceGen
• And move to Pretender.Internals namespace
• pragma disable obsolete warnings
• More Behaviors
• Use CancellationToken everywhere

0.3.0

• Special case known good fake implementation over mocking
  • EphemeralDataProtectionProvider
  • TimeProvider
• Make Pretend Implementation castable to something you can get the Pretend out of

Future Ideas

• What can I do with things that are protected or sealed
• Analyze all the things
• Custom awaitable (honestly don't think I care)
• Analyze constructor args them for likely match
• Debugger story
  • What do we want to step into
  • What objects will they inspect and how can it be helpful
• Documentation