Suggestion

error-prone-contrib/src/main/java/tech/picnic/errorprone/refasterrules/StreamRules.java

@@ -626,20 +626,9 @@ R after(
     }
   }
 
-  static final class StreamConcat<T> {
-    @BeforeTemplate
-    Stream<T> before(Stream<T> s1, Stream<T> s2) {
-      return Stream.of(s1, s2).flatMap(Function.identity());
-    }
-
-    @AfterTemplate
-    Stream<T> after(Stream<T> s1, Stream<T> s2) {
-      return Stream.concat(s1, s2);
-    }
-  }
-
   static final class StreamsConcat<T> {
     @BeforeTemplate
+    @SuppressWarnings("StreamOfArray")
     Stream<T> before(@Repeated Stream<T> stream) {
       return Stream.of(Refaster.asVarargs(stream)).flatMap(Function.identity());
     }

error-prone-contrib/src/test/resources/tech/picnic/errorprone/refasterrules/StreamRulesTestInput.java

@@ -251,10 +251,6 @@ ImmutableSet<Integer> testStreamFlatMapCollect() {
     return Stream.of(1).collect(flatMapping(n -> Stream.of(n, n), toImmutableSet()));
   }
 
-  Stream<Integer> testStreamConcat() {
-    return Stream.of(Stream.of(1), Stream.of(2)).flatMap(Function.identity());
-  }
-
   Stream<Integer> testStreamsConcat() {
     return Stream.of(Stream.of(1), Stream.of(2), Stream.of(3), Stream.of(4))
         .flatMap(Function.identity());

error-prone-contrib/src/test/resources/tech/picnic/errorprone/refasterrules/StreamRulesTestOutput.java

@@ -252,10 +252,6 @@ ImmutableSet<Integer> testStreamFlatMapCollect() {
     return Stream.of(1).flatMap(n -> Stream.of(n, n)).collect(toImmutableSet());
   }
 
-  Stream<Integer> testStreamConcat() {
-    return Stream.concat(Stream.of(1), Stream.of(2));
-  }
-
   Stream<Integer> testStreamsConcat() {
     return Streams.concat(Stream.of(1), Stream.of(2), Stream.of(3), Stream.of(4));
   }