fix: avoid null exception when received body is empty but recorded bo…

…dy isn't

EasyVCR.Tests/ClientTest.cs

@@ -512,6 +512,29 @@ public async Task TestMatchNonJsonBody()
  var response = await client.PostAsync(url, content);
  Assert.IsNotNull(response);
  }
+
+ [TestMethod]
+ public async Task TestMatchEmptyStringBodyToNonEmptyStringBody()
+ {
+ var cassette = TestUtils.GetCassette("test_match_empty_body");
+ cassette.Erase(); // Erase cassette before recording
+
+ const string url = "https://httpbin.org/post";
+
+ // record baseline request first
+ var client = HttpClients.NewHttpClient(cassette, Mode.Record);
+ var someContent = new ByteArrayContent(Encoding.UTF8.GetBytes("whatevs"));
+ _ = await client.PostAsync(url, someContent);
+
+ // try to replay the request with match by body enforcement
+ client = HttpClients.NewHttpClient(cassette, Mode.Replay, new AdvancedSettings
+ {
+ MatchRules = new MatchRules().ByBody()
+ });
+ var emptyContent = new ByteArrayContent(Encoding.UTF8.GetBytes(string.Empty));
+ Assert.ThrowsExceptionAsync<VCRException>(async () => await client.PostAsync(url, emptyContent), "No interaction found for request POST https://httpbin.org/post");
+ }
+
 
 
  [TestMethod]

EasyVCR/MatchRules.cs

@@ -159,7 +159,7 @@ public MatchRules ByBody(List<CensorElement>? ignoredElements = null)
  // both have empty string bodies, so they match
  return true;
 
- return receivedBody!.Equals(recordedBody, StringComparison.OrdinalIgnoreCase);
+ return (receivedBody ?? "").Equals(recordedBody, StringComparison.OrdinalIgnoreCase);
  });
  return this;
  }