up

src/Scanner/__Tests/StellaOps.Scanner.Analyzers.Lang.Tests/Harness/LanguageAnalyzerTestHarness.cs

@@ -1,9 +1,9 @@
-using StellaOps.Scanner.Analyzers.Lang;
-
-namespace StellaOps.Scanner.Analyzers.Lang.Tests.Harness;
-
-public static class LanguageAnalyzerTestHarness
-{
+using StellaOps.Scanner.Analyzers.Lang;
+
+namespace StellaOps.Scanner.Analyzers.Lang.Tests.Harness;
+
+public static class LanguageAnalyzerTestHarness
+{
     public static async Task<string> RunToJsonAsync(string fixturePath, IEnumerable<ILanguageAnalyzer> analyzers, CancellationToken cancellationToken = default, LanguageUsageHints? usageHints = null, IServiceProvider? services = null)
     {
         if (string.IsNullOrWhiteSpace(fixturePath))
@@ -14,33 +14,48 @@ public static class LanguageAnalyzerTestHarness
         var engine = new LanguageAnalyzerEngine(analyzers ?? Array.Empty<ILanguageAnalyzer>());
         var context = new LanguageAnalyzerContext(fixturePath, TimeProvider.System, usageHints, services);
         var result = await engine.AnalyzeAsync(context, cancellationToken).ConfigureAwait(false);
-        return result.ToJson(indent: true);
+        var json = result.ToJson(indent: true);
+
+        // Persist last run output for debugging determinism and fixture drift.
+        try
+        {
+            var outputDir = Path.Combine(AppContext.BaseDirectory, "TestResults");
+            Directory.CreateDirectory(outputDir);
+            var outputPath = Path.Combine(outputDir, "last-output.json");
+            await File.WriteAllTextAsync(outputPath, json, cancellationToken).ConfigureAwait(false);
+        }
+        catch
+        {
+            // Non-fatal; used only for local inspection.
+        }
+
+        return json;
     }
 
     public static async Task AssertDeterministicAsync(string fixturePath, string goldenPath, IEnumerable<ILanguageAnalyzer> analyzers, CancellationToken cancellationToken = default, LanguageUsageHints? usageHints = null, IServiceProvider? services = null)
     {
         var actual = await RunToJsonAsync(fixturePath, analyzers, cancellationToken, usageHints, services).ConfigureAwait(false);
         var expected = await File.ReadAllTextAsync(goldenPath, cancellationToken).ConfigureAwait(false);
-
-        // Normalize newlines for portability.
-        actual = NormalizeLineEndings(actual).TrimEnd();
-        expected = NormalizeLineEndings(expected).TrimEnd();
-
-        if (!string.Equals(expected, actual, StringComparison.Ordinal))
-        {
-            var actualPath = goldenPath + ".actual";
-            var directory = Path.GetDirectoryName(actualPath);
-            if (!string.IsNullOrEmpty(directory))
-            {
-                Directory.CreateDirectory(directory);
-            }
-
-            await File.WriteAllTextAsync(actualPath, actual, cancellationToken).ConfigureAwait(false);
-        }
-
-        Assert.Equal(expected, actual);
-    }
-
-    private static string NormalizeLineEndings(string value)
-        => value.Replace("\r\n", "\n", StringComparison.Ordinal);
-}
+
+        // Normalize newlines for portability.
+        actual = NormalizeLineEndings(actual).TrimEnd();
+        expected = NormalizeLineEndings(expected).TrimEnd();
+
+        if (!string.Equals(expected, actual, StringComparison.Ordinal))
+        {
+            var actualPath = goldenPath + ".actual";
+            var directory = Path.GetDirectoryName(actualPath);
+            if (!string.IsNullOrEmpty(directory))
+            {
+                Directory.CreateDirectory(directory);
+            }
+
+            await File.WriteAllTextAsync(actualPath, actual, cancellationToken).ConfigureAwait(false);
+        }
+
+        Assert.Equal(expected, actual);
+    }
+
+    private static string NormalizeLineEndings(string value)
+        => value.Replace("\r\n", "\n", StringComparison.Ordinal);
+}