MockQueryable

Extensions for mocking Entity Framework Core async queries like ToListAsync, FirstOrDefaultAsync, and more using popular mocking libraries such as Moq, NSubstitute, and FakeItEasy — all without hitting the database.

❤️ If you really like the tool, please 👉 Support the project or ☕ Buy me a coffee.

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📦 NuGet Packages:

Package	Latest Version	Install via Package Manager
		Install-Package MockQueryable.Core
		Install-Package MockQueryable.EntityFrameworkCore
		Install-Package MockQueryable.Moq
		Install-Package MockQueryable.NSubstitute
		Install-Package MockQueryable.FakeItEasy

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✅ Build & Status

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⭐ GitHub Stats

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💡 Why Use MockQueryable?

Avoid hitting the real database in unit tests when querying via IQueryable:

varquery=_userRepository.GetQueryable();awaitquery.AnyAsync(x => ...);awaitquery.FirstOrDefaultAsync(x => ...);awaitquery.ToListAsync();// etc.

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How It Works

MockQueryable creates a custom implementation of:

• IQueryable<T>
• IAsyncEnumerable<T>
• IAsyncQueryProvider

allowing EF Core async extensions to execute against in-memory collections.

👷🏻‍See Architecture.

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🚀 Getting Started

1. Create Test Data

varusers=newList<UserEntity>{newUserEntity{LastName="Smith",DateOfBirth=newDateTime(2012,1,20)},// More test data...};

2. Build the Mock

varmock=users.BuildMock();// for IQueryable

3. Set Up in Your favorite Mocking Framework

Moq

_userRepository.Setup(x =>x.GetQueryable()).Returns(mock);

NSubstitute

_userRepository.GetQueryable().Returns(mock);

FakeItEasy

A.CallTo(()=>userRepository.GetQueryable()).Returns(mock);

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🗃️ Mocking DbSet<T>

varmockDbSet=users.BuildMockDbSet();// Moqvarrepo=newTestDbSetRepository(mockDbSet.Object);// NSubstitute / FakeItEasyvarrepo=newTestDbSetRepository(mockDbSet);

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🔧 Adding Custom Logic

Example: Custom FindAsync

mock.Setup(x =>x.FindAsync(userId)).ReturnsAsync((object[]ids)=>{varid=(Guid)ids[0];returnusers.FirstOrDefault(x =>x.Id==id);});

Example: Custom Expression Visitor

Build a mock with the custom SampleLikeExpressionVisitor for testing EF.Functions.Like

varmockDbSet=users.BuildMockDbSet<UserEntity,SampleLikeExpressionVisitor>();

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🧩 Extend for Other Frameworks

You can even create your own extensions. Check the example here.

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🔍 Sample Project

See the sample project for working examples.

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