fix: diagnostic converter when location is empty (#290)

src/SampleGenerator/HelloWorldVbGenerator.cs

@@ -36,17 +36,20 @@ End Module
             DiagnosticSeverity.Info,
             isEnabledByDefault: true);
 
-        var location = Location.Create(
-            Path.Combine("dir", "theFile.vb"),
-            new(1, 2),
-            new(
-                new(1, 2),
-                new(3, 4)));
+        var location = GetLocation();
         var diagnostic = Diagnostic.Create(descriptor, location, "hello world generator");
         context.ReportDiagnostic(diagnostic);
     }
 
     public void Initialize(GeneratorInitializationContext context)
     {
     }
+
+    protected virtual Location? GetLocation() =>
+        Location.Create(
+            Path.Combine("dir", "theFile.vb"),
+            new(1, 2),
+            new(
+                new(1, 2),
+                new(3, 4)));
 }

src/SampleGenerator/HelloWorldVbGeneratorWithoutLocation.cs

@@ -0,0 +1,8 @@
+using Microsoft.CodeAnalysis;
+
+[Generator]
+public class HelloWorldVbGeneratorWithoutLocation :
+    HelloWorldVbGenerator
+{
+    protected override Location? GetLocation() => null;
+}

src/Tests/SampleVbTest.DriverWithoutLocation#helloWorld.verified.vb

@@ -0,0 +1,8 @@
+//HintName: helloWorld.vb
+Imports System
+
+Public Module HelloWorld
+    Public Sub SayHello()
+        Console.WriteLine("Hello from generated code!")
+    End Sub
+End Module

src/Tests/SampleVbTest.DriverWithoutLocation#helper.verified.vb

@@ -0,0 +1,6 @@
+//HintName: helper.vb
+Imports System
+Public Module Helper
+    Public Sub Method()
+    End Sub
+End Module

src/Tests/SampleVbTest.DriverWithoutLocation.verified.txt

@@ -0,0 +1,13 @@
+{
+  Diagnostics: [
+    {
+      Id: theId,
+      Title: the title,
+      Severity: Info,
+      WarningLevel: 1,
+      MessageFormat: the message from {0},
+      Message: the message from hello world generator,
+      Category: the category
+    }
+  ]
+}

src/Tests/SampleVbTest.RunResultWithoutLocation.verified.txt

@@ -0,0 +1,36 @@
+{
+  Generator: {},
+  GeneratedSources: [
+    {
+      HintName: helper.vb,
+      Source:
+Imports System
+Public Module Helper
+    Public Sub Method()
+    End Sub
+End Module
+    },
+    {
+      HintName: helloWorld.vb,
+      Source:
+Imports System
+
+Public Module HelloWorld
+    Public Sub SayHello()
+        Console.WriteLine("Hello from generated code!")
+    End Sub
+End Module
+    }
+  ],
+  Diagnostics: [
+    {
+      Id: theId,
+      Title: the title,
+      Severity: Info,
+      WarningLevel: 1,
+      MessageFormat: the message from {0},
+      Message: the message from hello world generator,
+      Category: the category
+    }
+  ]
+}

src/Tests/SampleVbTest.RunResultsWithoutLocation#helloWorld.verified.vb

@@ -0,0 +1,8 @@
+//HintName: helloWorld.vb
+Imports System
+
+Public Module HelloWorld
+    Public Sub SayHello()
+        Console.WriteLine("Hello from generated code!")
+    End Sub
+End Module

src/Tests/SampleVbTest.RunResultsWithoutLocation#helper.verified.vb

@@ -0,0 +1,6 @@
+//HintName: helper.vb
+Imports System
+Public Module Helper
+    Public Sub Method()
+    End Sub
+End Module

src/Tests/SampleVbTest.RunResultsWithoutLocation.verified.txt

@@ -0,0 +1,13 @@
+{
+  Diagnostics: [
+    {
+      Id: theId,
+      Title: the title,
+      Severity: Info,
+      WarningLevel: 1,
+      MessageFormat: the message from {0},
+      Message: the message from hello world generator,
+      Category: the category
+    }
+  ]
+}

src/Tests/SampleVbTest.cs

@@ -5,15 +5,15 @@ public class SampleVbTest
     [Fact]
     public Task Driver()
     {
-        var driver = BuildDriver();
+        var driver = BuildDriver<HelloWorldVbGenerator>();
 
         return Verify(driver);
     }
 
     [Fact]
     public Task RunResults()
     {
-        var driver = BuildDriver();
+        var driver = BuildDriver<HelloWorldVbGenerator>();
 
         var results = driver.GetRunResult();
         return Verify(results);
@@ -22,16 +22,43 @@ public Task RunResults()
     [Fact]
     public Task RunResult()
     {
-        var driver = BuildDriver();
+        var driver = BuildDriver<HelloWorldVbGenerator>();
 
         var result = driver.GetRunResult().Results.Single();
         return Verify(result);
     }
 
-    static GeneratorDriver BuildDriver()
+    [Fact]
+    public Task DriverWithoutLocation()
+    {
+        var driver = BuildDriver<HelloWorldVbGeneratorWithoutLocation>();
+
+        return Verify(driver);
+    }
+
+    [Fact]
+    public Task RunResultsWithoutLocation()
+    {
+        var driver = BuildDriver<HelloWorldVbGeneratorWithoutLocation>();
+
+        var results = driver.GetRunResult();
+        return Verify(results);
+    }
+
+    [Fact]
+    public Task RunResultWithoutLocation()
+    {
+        var driver = BuildDriver<HelloWorldVbGeneratorWithoutLocation>();
+
+        var result = driver.GetRunResult().Results.Single();
+        return Verify(result);
+    }
+
+    static GeneratorDriver BuildDriver<T>()
+        where T : ISourceGenerator, new()
     {
         var compilation = VisualBasicCompilation.Create("name");
-        var generator = new HelloWorldVbGenerator();
+        var generator = new T();
 
         var vbGeneratorDriver = VisualBasicGeneratorDriver.Create([generator]);
         return vbGeneratorDriver.RunGenerators(compilation);

src/Verify.SourceGenerators/Converters/DiagnosticConverter.cs

@@ -9,7 +9,10 @@ public override void Write(VerifyJsonWriter writer, Diagnostic value)
         writer.WriteMember(value, descriptor.Title, "Title");
         writer.WriteMember(value, value.Severity, "Severity");
         writer.WriteMember(value, value.WarningLevel, "WarningLevel");
-        writer.WriteMember(value, value.Location, "Location");
+        if (value.Location != Location.None)
+        {
+            writer.WriteMember(value, value.Location, "Location");
+        }
         var description = descriptor.Description.ToString(CultureInfo.InvariantCulture);
         if (!string.IsNullOrWhiteSpace(description))
         {

src/Verify.SourceGenerators/Converters/FileLinePositionSpanConverter.cs

@@ -1,11 +1,6 @@
 class FileLinePositionSpanConverter :
     WriteOnlyJsonConverter<FileLinePositionSpan>
 {
-    public override void Write(VerifyJsonWriter writer, FileLinePositionSpan value)
-    {
-        if (value.IsValid)
-        {
-            writer.WriteValue($"{value.Path.Replace('/', '\\')}: {value.Span}");
-        }
-    }
+    public override void Write(VerifyJsonWriter writer, FileLinePositionSpan value) =>
+        writer.WriteValue(value.IsValid ? $"{value.Path.Replace('/', '\\')}: {value.Span}" : "");
 }