Preserve parameterized toString assertions

src/main/java/org/openrewrite/java/testing/assertj/SimplifyChainedAssertJAssertion.java

@@ -123,6 +123,10 @@ public J.MethodInvocation visitMethodInvocation(J.MethodInvocation methodInvocat
                 if (!chainedAssertMatcher.matches(assertThatArg)) {
                     return mi;
                 }
+                // Parameterized toString overloads have no equivalent hasToString assertion.
+                if ("toString".equals(chainedAssertion) && !(assertThatArg.getArguments().get(0) instanceof J.Empty)) {
+                    return mi;
+                }
 
                 // Extract the actual argument for the new assertThat call
                 Expression actual = assertThatArg.getSelect() != null ? assertThatArg.getSelect() : assertThatArg;

src/test/java/org/openrewrite/java/testing/assertj/SimplifyChainedAssertJAssertionsTest.java

@@ -467,4 +467,24 @@ void testMethod(Object argument) {
             );
         }
     }
+
+    @Test
+    void doesNotRewriteParameterizedByteArrayOutputStreamToString() {
+        rewriteRun(
+          java(
+            """
+              import java.io.ByteArrayOutputStream;
+              import java.nio.charset.StandardCharsets;
+
+              import static org.assertj.core.api.Assertions.assertThat;
+
+              class Test {
+                  void verify(ByteArrayOutputStream stdout, String expected) {
+                      assertThat(stdout.toString(StandardCharsets.UTF_8)).isEqualTo(expected);
+                  }
+              }
+              """
+          )
+        );
+    }
 }