Extend CollectionIsEmpty Refaster rule (#1027)

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/LexicographicalAnnotationAttributeListing.java

@@ -51,6 +51,9 @@ import tech.picnic.errorprone.utils.SourceCode;
  * <p>The idea behind this checker is that maintaining a sorted sequence simplifies conflict
  * resolution, and can even avoid it if two branches add the same entry.
  */
+// XXX: In some places we declare a `@SuppressWarnings` annotation with a final value of
+// `key-to-resolve-AnnotationUseStyle-and-TrailingComment-check-conflict`. That entry must stay
+// last. Consider adding (generic?) support for such cases.
 @AutoService(BugChecker.class)
 @BugPattern(
     summary = "Where possible, sort annotation array attributes lexicographically",

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

@@ -35,13 +35,21 @@ final class CollectionRules {
    */
   static final class CollectionIsEmpty<T> {
     @BeforeTemplate
-    @SuppressWarnings("java:S1155" /* This violation will be rewritten. */)
+    @SuppressWarnings({
+      "java:S1155" /* This violation will be rewritten. */,
+      "LexicographicalAnnotationAttributeListing" /* `key-*` entry must remain last. */,
+      "OptionalFirstCollectionElement" /* This is a more specific template. */,
+      "StreamIsEmpty" /* This is a more specific template. */,
+      "key-to-resolve-AnnotationUseStyle-and-TrailingComment-check-conflict"
+    })
     boolean before(Collection<T> collection) {
       return Refaster.anyOf(
           collection.size() == 0,
           collection.size() <= 0,
           collection.size() < 1,
-          Iterables.isEmpty(collection));
+          Iterables.isEmpty(collection),
+          collection.stream().findAny().isEmpty(),
+          collection.stream().findFirst().isEmpty());
     }
 
     @BeforeTemplate
@@ -337,7 +345,9 @@ final class CollectionRules {
 
   /**
    * Don't use the ternary operator to extract the first element of a possibly-empty {@link
-   * Collection} as an {@link Optional}.
+   * Collection} as an {@link Optional}, and (when applicable) prefer {@link Stream#findFirst()}
+   * over {@link Stream#findAny()} to communicate that the collection's first element (if any,
+   * according to iteration order) will be returned.
    */
   static final class OptionalFirstCollectionElement<T> {
     @BeforeTemplate

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

@@ -29,7 +29,9 @@ final class CollectionRulesTest implements RefasterRuleCollectionTestCase {
         ImmutableSet.of(5).size() > 0,
         ImmutableSet.of(6).size() >= 1,
         Iterables.isEmpty(ImmutableSet.of(7)),
-        ImmutableSet.of(8).asList().isEmpty());
+        ImmutableSet.of(8).stream().findAny().isEmpty(),
+        ImmutableSet.of(9).stream().findFirst().isEmpty(),
+        ImmutableSet.of(10).asList().isEmpty());
   }
 
   ImmutableSet<Integer> testCollectionSize() {

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

@@ -29,7 +29,9 @@ final class CollectionRulesTest implements RefasterRuleCollectionTestCase {
         !ImmutableSet.of(5).isEmpty(),
         !ImmutableSet.of(6).isEmpty(),
         ImmutableSet.of(7).isEmpty(),
-        ImmutableSet.of(8).isEmpty());
+        ImmutableSet.of(8).isEmpty(),
+        ImmutableSet.of(9).isEmpty(),
+        ImmutableSet.of(10).isEmpty());
   }
 
   ImmutableSet<Integer> testCollectionSize() {