Verify.SourceGenerators
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Extends Verify to allow verification of C# Source Generators.
Verify.SourceGenerators
Extends Verify to allow verification of C# Source Generators.
See Milestones for release notes.
NuGet package
https://nuget.org/packages/Verify.SourceGenerators/
Install one of the Verify testing framework adapters NuGet packages.
Initialize
[ModuleInitializer]
public static void Init() =>
VerifySourceGenerators.Initialize();
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Generator
Given a Source Generator:
using Microsoft.CodeAnalysis;
using Microsoft.CodeAnalysis.Text;
[Generator]
public class HelloWorldGenerator :
ISourceGenerator
{
public void Execute(GeneratorExecutionContext context)
{
var source1 = """
using System;
public static class Helper
{
public static void Method()
{
}
}
""";
context.AddSource("helper", SourceText.From(source1, Encoding.UTF8));
var source2 = """
using System;
public static class HelloWorld
{
public static void SayHello()
{
Console.WriteLine("Hello from generated code!");
}
}
""";
context.AddSource("helloWorld", SourceText.From(source2, Encoding.UTF8));
var descriptor = new DiagnosticDescriptor(
id: "theId",
title: "the title",
messageFormat: "the message from {0}",
category: "the category",
DiagnosticSeverity.Info,
isEnabledByDefault: true);
var location = Location.Create(
"theFile",
new(1, 2),
new(
new(1, 2),
new(3, 4)));
var diagnostic = Diagnostic.Create(descriptor, location, "hello world generator");
context.ReportDiagnostic(diagnostic);
}
public void Initialize(GeneratorInitializationContext context)
{
}
}
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Test
Can be tested as follows:
This snippets assumes use of the XUnit Verify adapter, change the using VerifyXUnit
if using other testing frameworks.
using Microsoft.CodeAnalysis;
using Microsoft.CodeAnalysis.CSharp;
public class SampleTest
{
[Fact]
public Task Driver()
{
var driver = GeneratorDriver();
return Verify(driver);
}
[Fact]
public Task RunResults()
{
var driver = GeneratorDriver();
var runResults = driver.GetRunResult();
return Verify(runResults);
}
[Fact]
public Task RunResult()
{
var driver = GeneratorDriver();
var runResult = driver.GetRunResult().Results.Single();
return Verify(runResult);
}
static GeneratorDriver GeneratorDriver()
{
var compilation = CSharpCompilation.Create("name");
var generator = new HelloWorldGenerator();
var driver = CSharpGeneratorDriver.Create(generator);
return driver.RunGenerators(compilation);
}
}
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Results
And will result in the following verified files:
Info file
An info file containing all metadata about the current state. eg any Diagnostics.
{
Diagnostics: [
{
Id: theId,
Title: the title,
Severity: Info,
WarningLevel: 1,
Location: theFile: (1,2)-(3,4),
MessageFormat: the message from {0},
Message: the message from hello world generator,
Category: the category
}
]
}
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Source Files
Multiple source files. One for each GeneratorDriverRunResult.Results.GeneratedSources
.
//HintName: helloWorld.cs
using System;
public static class HelloWorld
{
public static void SayHello()
{
Console.WriteLine("Hello from generated code!");
}
}
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Manipulating Source
To manipulating the source of the generated cs files, use Scrubbers.
For example to remove all lines start with using
:
[Fact]
public Task ScrubLines()
{
var driver = GeneratorDriver();
return Verify(driver)
.ScrubLines(_ => _.StartsWith("using "));
}
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Notes:
Icon
Sauce designed by April Hsuan from The Noun Project.