Introduce OptionalIdentity Refaster template

error-prone-contrib/src/main/java/tech/picnic/errorprone/refastertemplates/OptionalTemplates.java

@@ -332,6 +332,22 @@ Optional<T> after(Optional<T> optional1, Optional<T> optional2) {
     }
   }
 
+  /**
+   * Don't use the redundant chain of {@link Optional#stream()} followed by either {@link
+   * Stream#findFirst()} or {@link Stream#findAny()}.
+   */
+  abstract static class OptionalSkipStreamFindFirst<T> {
+    @BeforeTemplate
+    Optional<T> before(Optional<T> optional) {
+      return Refaster.anyOf(optional.stream().findFirst(), optional.stream().findAny());
+    }
+
+    @AfterTemplate
+    Optional<T> after(Optional<T> optional) {
+      return optional;
+    }
+  }
+
   // XXX: Add a rule for:
   // `optional.flatMap(x -> pred(x) ? Optional.empty() : Optional.of(x))` and variants.
   // (Maybe canonicalize the inner expression. Maybe we rewrite already.)

error-prone-contrib/src/test/resources/tech/picnic/errorprone/refastertemplates/OptionalTemplatesTestInput.java

@@ -101,4 +101,9 @@ ImmutableSet<Optional<String>> testOptionalOrOtherOptional() {
         Optional.of("baz").map(Optional::of).orElseGet(() -> Optional.of("qux")),
         Stream.of(Optional.of("quux"), Optional.of("quuz")).flatMap(Optional::stream).findFirst());
   }
+
+  ImmutableSet<Optional<String>> testOptionalSkipStreamFindFirst() {
+    return ImmutableSet.of(
+        Optional.of("foo").stream().findFirst(), Optional.of("bar").stream().findAny());
+  }
 }

error-prone-contrib/src/test/resources/tech/picnic/errorprone/refastertemplates/OptionalTemplatesTestOutput.java

@@ -98,4 +98,8 @@ ImmutableSet<Optional<String>> testOptionalOrOtherOptional() {
         Optional.of("baz").or(() -> Optional.of("qux")),
         Optional.of("quux").or(() -> Optional.of("quuz")));
   }
+
+  ImmutableSet<Optional<String>> testOptionalSkipStreamFindFirst() {
+    return ImmutableSet.of(Optional.of("foo"), Optional.of("bar"));
+  }
 }