save progress

src/__Libraries/StellaOps.Canonicalization/Verification/DeterminismVerifier.cs

@@ -42,12 +42,40 @@ public sealed class DeterminismVerifier
     private static IReadOnlyList<string> FindDifferences(string a, string b)
     {
         var differences = new List<string>();
-        using var docA = JsonDocument.Parse(a);
-        using var docB = JsonDocument.Parse(b);
-        CompareElements(docA.RootElement, docB.RootElement, "$", differences);
+        var parsedA = TryParseJson(a, "inputA", differences, out var docA);
+        var parsedB = TryParseJson(b, "inputB", differences, out var docB);
+        if (!parsedA || !parsedB)
+        {
+            return differences;
+        }
+
+        using (docA)
+        using (docB)
+        {
+            CompareElements(docA.RootElement, docB.RootElement, "$", differences);
+        }
         return differences;
     }
 
+    private static bool TryParseJson(
+        string json,
+        string label,
+        List<string> differences,
+        out JsonDocument doc)
+    {
+        try
+        {
+            doc = JsonDocument.Parse(json);
+            return true;
+        }
+        catch (JsonException ex)
+        {
+            differences.Add($"{label}: invalid JSON ({ex.Message})");
+            doc = null!;
+            return false;
+        }
+    }
+
     private static void CompareElements(JsonElement a, JsonElement b, string path, List<string> differences)
     {
         if (a.ValueKind != b.ValueKind)