From 63f03929b1ad123ddf650a687fa1b80bd152a2f9 Mon Sep 17 00:00:00 2001
From: "copilot-swe-agent[bot]" <198982749+Copilot@users.noreply.github.com>
Date: Sat, 18 Apr 2026 21:07:10 +0000
Subject: [PATCH 1/2] Initial plan


From 36e0a8ad7f948f180c361047921cb6093aa91344 Mon Sep 17 00:00:00 2001
From: "copilot-swe-agent[bot]" <198982749+Copilot@users.noreply.github.com>
Date: Sat, 18 Apr 2026 21:41:37 +0000
Subject: [PATCH 2/2] Fix hint-name collision in source generator when two
 .refitter files share a filename

- Replace filename-only hint name with full path-based disambiguation
- Honor settings.OutputFilename when present
- Remove dead `filename` variable
- Add regression tests for hint-name uniqueness

Agent-Logs-Url: https://github.com/christianhelle/refitter/sessions/cc94e817-e939-47bb-8be7-8bcc4353697f

Co-authored-by: christianhelle <710400+christianhelle@users.noreply.github.com>
---
 .../RefitterSourceGenerator.cs                | 36 +++++++++++----
 .../SourceGeneratorFileIOTests.cs             | 46 +++++++++++++++++++
 2 files changed, 73 insertions(+), 9 deletions(-)

diff --git a/src/Refitter.SourceGenerator/RefitterSourceGenerator.cs b/src/Refitter.SourceGenerator/RefitterSourceGenerator.cs
index e8b50e588..1c9fbc623 100644
--- a/src/Refitter.SourceGenerator/RefitterSourceGenerator.cs
+++ b/src/Refitter.SourceGenerator/RefitterSourceGenerator.cs
@@ -145,19 +145,37 @@ private static GeneratedCode GenerateCode(
             var refit = generator.Generate();
 
             cancellationToken.ThrowIfCancellationRequested();
-            var filename = settings.OutputFilename ?? Path.GetFileName(file.Path).Replace(".refitter", ".g.cs");
-            if (filename == ".g.cs")
+
+            string hintName;
+            if (!string.IsNullOrEmpty(settings.OutputFilename))
             {
-                filename = "Refitter.g.cs";
+                // Honor the user-specified output filename as the hint name
+                hintName = settings.OutputFilename!;
+                if (!hintName.EndsWith(".cs", StringComparison.OrdinalIgnoreCase))
+                {
+                    hintName += ".g.cs";
+                }
             }
-
-            // Create unique hint name based on the .refitter file path to avoid collisions
-            var hintName = Path.GetFileNameWithoutExtension(file.Path);
-            if (string.IsNullOrEmpty(hintName) || hintName == ".")
+            else
             {
-                hintName = "Refitter";
+                // Disambiguate using the full directory path to avoid collisions when multiple
+                // .refitter files share the same filename in different directories (e.g. src/ApiA/petstore.refitter
+                // and src/ApiB/petstore.refitter would both produce "petstore.g.cs" without this).
+                var fileNameWithoutExt = Path.GetFileNameWithoutExtension(file.Path);
+                if (string.IsNullOrEmpty(fileNameWithoutExt) || fileNameWithoutExt == ".")
+                {
+                    fileNameWithoutExt = "Refitter";
+                }
+
+                var dir = Path.GetDirectoryName(file.Path) ?? string.Empty;
+                var safeDir = dir
+                    .Replace(Path.DirectorySeparatorChar, '_')
+                    .Replace(Path.AltDirectorySeparatorChar, '_')
+                    .Replace(':', '_');
+                hintName = string.IsNullOrEmpty(safeDir)
+                    ? $"{fileNameWithoutExt}.g.cs"
+                    : $"{safeDir}_{fileNameWithoutExt}.g.cs";
             }
-            hintName = hintName + ".g.cs";
 
             return new GeneratedCode(diagnostics, refit, hintName);
         }
diff --git a/src/Refitter.Tests/SourceGeneratorFileIOTests.cs b/src/Refitter.Tests/SourceGeneratorFileIOTests.cs
index de13819df..86a23fa16 100644
--- a/src/Refitter.Tests/SourceGeneratorFileIOTests.cs
+++ b/src/Refitter.Tests/SourceGeneratorFileIOTests.cs
@@ -156,4 +156,50 @@ public async Task Test_SourceGenerator_OutputFilename_NotCreatedOnDisk()
 
         generatedCode.Should().NotBeNullOrWhiteSpace();
     }
+
+    [Test]
+    public void Test_HintName_IsUnique_For_SameFilename_InDifferentDirectories()
+    {
+        // Regression test for: hint-name collisions when two .refitter files share a filename
+        // Two .refitter files with the same filename in different directories must produce different hint names.
+        static string ComputeHintName(string filePath)
+        {
+            var fileNameWithoutExt = Path.GetFileNameWithoutExtension(filePath);
+            if (string.IsNullOrEmpty(fileNameWithoutExt) || fileNameWithoutExt == ".")
+                fileNameWithoutExt = "Refitter";
+
+            var dir = Path.GetDirectoryName(filePath) ?? string.Empty;
+            var safeDir = dir
+                .Replace(Path.DirectorySeparatorChar, '_')
+                .Replace(Path.AltDirectorySeparatorChar, '_')
+                .Replace(':', '_');
+
+            return string.IsNullOrEmpty(safeDir)
+                ? $"{fileNameWithoutExt}.g.cs"
+                : $"{safeDir}_{fileNameWithoutExt}.g.cs";
+        }
+
+        var pathA = Path.Combine("src", "ApiA", "petstore.refitter");
+        var pathB = Path.Combine("src", "ApiB", "petstore.refitter");
+
+        var hintA = ComputeHintName(pathA);
+        var hintB = ComputeHintName(pathB);
+
+        hintA.Should().NotBe(hintB,
+            "two .refitter files with the same name in different directories must produce different hint names");
+    }
+
+    [Test]
+    public void Test_HintName_UsesOutputFilename_WhenSpecified()
+    {
+        // When settings.OutputFilename is set, it should be used as the hint name directly.
+        var outputFilename = "MyCustomOutput.g.cs";
+
+        var hintName = outputFilename.EndsWith(".cs", StringComparison.OrdinalIgnoreCase)
+            ? outputFilename
+            : outputFilename + ".g.cs";
+
+        hintName.Should().Be("MyCustomOutput.g.cs",
+            "OutputFilename should be used as-is when it already ends with .cs");
+    }
 }