LPRun 9.6.2

LINQPad Driver LPRun Unit/Integration Tests Runner

Table of Contents

• Description
• .NET Versions Supported
• Download
• Usage
  • Setup
  • LINQPad Test Script Example
  • NUnit Test Example
• Known Issues
  • Unit-testing Frameworks Support
  • macOS support
  • LINQPad Runtime Reference
• Troubleshooting
• Authors
• Credits
  • Tools
  • NuGet
• Licenses

Description

The LPRun is the LINQPad driver's unit/integration tests runner. Can be used for testing LINQPad drivers, e.g., CsvLINQPadDriver for LINQPad, or for running LINQPad scripts.

.NET Versions Supported

Scripts targeting .NET 6 up to .NET 10 are supported. Use the following LINQPad script to check which .NET is used by LPRun:

<Query Kind="Expression"/>

System.Environment.Version

Download

Usage

Tested driver MUST NOT be installed via NuGet into LINQPad. In this case LPRun will use it instead of local one.

Setup

1. Create test project.
2. Add LPRun
3. Create the following folder structure in test project:

LPRun # Created by LPRun NuGet.
    Templates # LINQPad script templates.
    Data      # Optional: Driver data files.

LINQPad Test Script Example

LPRun executes LINQPad test script. Test script uses AwesomeAssertions for assertion checks.

StringComparison.linq LINQPad test script example:

var original = Books.First();
var copy = original with { Title = original.Title.ToUpper() };

var expectedEquality = original.Title.Equals(copy.Title, context.StringComparison);

original.Equals(copy).Should().Be(expectedEquality, Reason());

original.GetHashCode()
    .Equals(copy.GetHashCode())
    .Should()
    .Be(expectedEquality, Reason());

Reason() method (prints exact line number if assertion fails) and context variable are injected by test below.

NUnit Test Example

Full NUnit test code can be found here.

[TestFixture]
public class LPRunTests
{
    [OneTimeSetUp]
    public void Init()
    {
        // Check that driver is not installed via NuGet.
        Driver.EnsureNotInstalledViaNuGet("CsvLINQPadDriver");

        // Install driver.
        Driver.InstallWithDepsJson(
            // The directory to copy driver files to.
            "CsvLINQPadDriver",
            // The LINQPad driver files.
            "CsvLINQPadDriver.dll",
            // The test folder path.
            "Tests");
    }

    [Test]
    [TestCaseSource(nameof(TestsData))]
    public async Task Execute_ScriptWithDriverProperties_Success(
        (string linqScriptName,
         string? context,
         ICsvDataContextDriverProperties driverProperties) testData)
    {
        var (linqScriptName, context, driverProperties) = testData;

        // Arrange: Create query connection header. Custom code can be added here.
        var queryConfig = GetQueryHeaders().Aggregate(
            new StringBuilder(),
            (stringBuilder, h) =>
        {
            stringBuilder.AppendLine(h);
            stringBuilder.AppendLine();
            return stringBuilder;
        }).ToString();

        // Arrange: Create test LNQPad script.
        // You can also use LinqScript.FromScript method.
        var linqScript = LinqScript.FromFile(
            $"{linqScriptName}.linq",
            queryConfig);

        // Act: Execute test LNQPad script.
        var (output, error, exitCode) =
            await Runner.ExecuteAsync(linqScript);

        // Assert.
        error.Should().BeNullOrWhiteSpace();
        exitCode.Should().Be(0);

        // Helpers.
        IEnumerable<string> GetQueryHeaders()
        {
            // Connection header.
            yield return ConnectionHeader.Get(
                "CsvLINQPadDriver",
                "CsvLINQPadDriver.CsvDataContextDriver",
                driverProperties,
                "System.Runtime.CompilerServices");

            // AwesomeAssertions helper.
            yield return
                 "string Reason([CallerLineNumber] int sourceLineNumber = 0) =>" +
                @" $""something went wrong at line #{sourceLineNumber}"";";

            // Test context.
            if (!string.IsNullOrWhiteSpace(context))
            {
                yield return $"var context = {context};";
            }
        }
    }

    private static IEnumerable<
        (string linqScriptName,
         string? context,
         ICsvDataContextDriverProperties driverProperties)> TestsData()
    {
        // Omitted for brevity.
    }
}

Tests can also be run in parallel:

[TestFixture]
public class LPRunTests
{
    [Test]
    [Parallelizable(ParallelScope.Children)]
    [TestCaseSource(nameof(ParallelizableTestsData))]
    public void Execute_ScriptWithDriverProperties_Success(
        (string linqScriptName,
         string? context,
         ICsvDataContextDriverProperties driverProperties,
         int index) testData)
    {
        // ...

        // Arrange: Create test LNQPad script.
        // You can also use LinqScript.FromScript method.
        var linqScript = LinqScript.FromFile(
            $"{linqScriptName}.linq",
            queryConfig,
            $"{linqScriptName}_{testData.index}");

        // ...
    }

    private static IEnumerable<
        (string linqScriptName,
         string? context,
         ICsvDataContextDriverProperties driverProperties,
         int index)> TestsData()
    {
        // Omitted for brevity.
    }

    // Parallelized tests data.
    private static IEnumerable<
        (string linqScriptName,
         string? context,
         ICsvDataContextDriverProperties driverProperties,
         int index)> ParallelizableTestsData() =>
        TestsData().AugmentWithFileIndex(
            static testData => testData.linqScriptName,
            static (testData, index) => { testData.index = index; return testData; });
}

Known Issues

Unit-testing Frameworks Support

Tested with NUnit. Other test frameworks should work as well.

macOS support

Running LPRun on macOS is not supported yet.

LINQPad Runtime Reference

Avoid referencing LINQPad.Runtime.dll in your tests, e.g. for Moq:

// LINQPad.Runtime.dll IConnectionInfo reference:
var connectionInfoMock = new Mock<LINQPad.Extensibility.DataContext.IConnectionInfo>();
var driverProperties   = new DriverProperties(connectionInfoMock.Object);

This code compiles but fails in runtime with Could not load file or assembly LINQPad.Runtime error. If you still need to reference it, add the following target which copies assembly to output folder of the test project:

<Target Name="CopyLINQPadRuntimeToOutput" AfterTargets="Build">
  <Copy SourceFiles="$(OutputPath)\LPRun\Bin\LINQPad.Runtime.dll" DestinationFolder="$(OutputPath)" UseHardlinksIfPossible="true" />
</Target>

Your can avoid referencing LINQPad.Runtime.dll assembly by using mock framework facilities, e.g. for Moq you can extract IDriverProperties interface and setup driver properties as follows:

var driverProperties = Mock.Of<IDriverProperties>(props =>
    props.BoolProp   == true     &&
    props.IntProp    == 42       &&
    props.StringProp == "string"
);

Authors

• Ivan Ivon
• LINQPad.Runtime/LPRun binaries (license) by Joseph Albahari

Credits

Tools

• LINQPad
• LINQPad Command-Line and Scripting

NuGet

• AwesomeAssertions
• Moq
• NUnit

Licenses

• LICENSE (MIT)
• LINQPad End User License Agreement