Introduce DequeRules Refaster rule collection (#1946)

Author: Stephan202

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

@@ -0,0 +1,154 @@
+package tech.picnic.errorprone.refasterrules;
+
+import com.google.errorprone.refaster.Refaster;
+import com.google.errorprone.refaster.annotation.AfterTemplate;
+import com.google.errorprone.refaster.annotation.BeforeTemplate;
+import com.google.errorprone.refaster.annotation.NotMatches;
+import java.util.Deque;
+import java.util.Iterator;
+import org.jspecify.annotations.Nullable;
+import tech.picnic.errorprone.refaster.annotation.OnlineDocumentation;
+import tech.picnic.errorprone.refaster.matchers.IsList;
+
+/** Refaster rules related to expressions dealing with {@link Deque} instances. */
+// XXX: Introduce similar rules for `BlockingDeque`.
+@OnlineDocumentation
+final class DequeRules {
+  private DequeRules() {}
+
+  /** Prefer {@link Deque#addLast(Object)} over less clear alternatives. */
+  static final class DequeAddFirst<S, T extends S> {
+    @BeforeTemplate
+    void before(Deque<S> deque, T element) {
+      deque.push(element);
+    }
+
+    @AfterTemplate
+    void after(Deque<S> deque, T element) {
+      deque.addFirst(element);
+    }
+  }
+
+  /**
+   * Prefer {@link Deque#addLast(Object)} over less clear alternatives.
+   *
+   * <p>Note: this rule does not match instances of type {@link java.util.List} (including {@link
+   * java.util.LinkedList}, which also implements {@link Deque}), as {@link
+   * java.util.List#add(Object)} is the idiomatic method for those types.
+   */
+  static final class DequeAddLast<S, T extends S> {
+    @BeforeTemplate
+    void before(@NotMatches(IsList.class) Deque<S> deque, T element) {
+      deque.add(element);
+    }
+
+    @AfterTemplate
+    void after(Deque<S> deque, T element) {
+      deque.addLast(element);
+    }
+  }
+
+  /** Prefer {@link Deque#removeFirst()} over less clear alternatives. */
+  static final class DequeRemoveFirst<S, T extends S> {
+    @BeforeTemplate
+    S before(Deque<T> deque) {
+      return Refaster.anyOf(deque.pop(), deque.remove());
+    }
+
+    @AfterTemplate
+    S after(Deque<T> deque) {
+      return deque.removeFirst();
+    }
+  }
+
+  /** Prefer {@link Deque#offerLast(Object)} over less clear alternatives. */
+  static final class DequeOfferLast<S, T extends S> {
+    @BeforeTemplate
+    boolean before(Deque<S> deque, T element) {
+      return deque.offer(element);
+    }
+
+    @AfterTemplate
+    boolean after(Deque<S> deque, T element) {
+      return deque.offerLast(element);
+    }
+  }
+
+  /** Prefer {@link Deque#pollFirst()} over less clear alternatives. */
+  static final class DequePollFirst<S, T extends S> {
+    @BeforeTemplate
+    @Nullable S before(Deque<T> deque) {
+      return deque.poll();
+    }
+
+    @AfterTemplate
+    @Nullable S after(Deque<T> deque) {
+      return deque.pollFirst();
+    }
+  }
+
+  /** Prefer {@link Deque#pollFirst()} over less clear alternatives. */
+  static final class DequeGetFirst<S, T extends S> {
+    @BeforeTemplate
+    S before(Deque<T> deque) {
+      return deque.element();
+    }
+
+    @AfterTemplate
+    S after(Deque<T> deque) {
+      return deque.getFirst();
+    }
+  }
+
+  /** Prefer {@link Deque#peekFirst()} over less clear alternatives. */
+  static final class DequePeekFirst<S, T extends S> {
+    @BeforeTemplate
+    @Nullable S before(Deque<T> deque) {
+      return deque.peek();
+    }
+
+    @AfterTemplate
+    @Nullable S after(Deque<T> deque) {
+      return deque.peekFirst();
+    }
+  }
+
+  /** Prefer {@link Deque#removeFirstOccurrence(Object)} over less clear alternatives. */
+  static final class DequeRemoveFirstOccurrence<S, T extends S> {
+    @BeforeTemplate
+    boolean before(Deque<S> deque, T element) {
+      return deque.remove(element);
+    }
+
+    @AfterTemplate
+    boolean after(Deque<S> deque, T element) {
+      return deque.removeFirstOccurrence(element);
+    }
+  }
+
+  /** Prefer {@link Deque#iterator()} over more contrived alternatives. */
+  static final class DequeIterator<T> {
+    @BeforeTemplate
+    Iterator<T> before(Deque<T> deque) {
+      return deque.reversed().descendingIterator();
+    }
+
+    @AfterTemplate
+    Iterator<T> after(Deque<T> deque) {
+      return deque.iterator();
+    }
+  }
+
+  /** Prefer {@link Deque#descendingIterator()} over more contrived alternatives. */
+  static final class DequeDescendingIterator<T> {
+    @BeforeTemplate
+    Iterator<T> before(Deque<T> deque) {
+      return deque.reversed().iterator();
+    }
+
+    @AfterTemplate
+    Iterator<T> after(Deque<T> deque) {
+      return deque.descendingIterator();
+    }
+  }
+}

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

@@ -48,6 +48,7 @@ final class RefasterRulesTest {
           ClassRules.class,
           CollectionRules.class,
           ComparatorRules.class,
+          DequeRules.class,
           DoubleStreamRules.class,
           EqualityRules.class,
           FileRules.class,

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

@@ -0,0 +1,50 @@
+package tech.picnic.errorprone.refasterrules;
+
+import com.google.common.collect.ImmutableSet;
+import java.util.ArrayDeque;
+import java.util.Iterator;
+import java.util.LinkedList;
+import tech.picnic.errorprone.refaster.test.RefasterRuleCollectionTestCase;
+
+final class DequeRulesTest implements RefasterRuleCollectionTestCase {
+  void testDequeAddFirst() {
+    new ArrayDeque<String>().push("foo");
+  }
+
+  void testDequeAddLast() {
+    new ArrayDeque<String>().add("foo");
+    new LinkedList<String>().add("bar");
+  }
+
+  ImmutableSet<String> testDequeRemoveFirst() {
+    return ImmutableSet.of(new ArrayDeque<String>(0).pop(), new ArrayDeque<String>(1).remove());
+  }
+
+  boolean testDequeOfferLast() {
+    return new ArrayDeque<String>().offer("foo");
+  }
+
+  String testDequePollFirst() {
+    return new ArrayDeque<String>().poll();
+  }
+
+  String testDequeGetFirst() {
+    return new ArrayDeque<String>().element();
+  }
+
+  String testDequePeekFirst() {
+    return new ArrayDeque<String>().peek();
+  }
+
+  boolean testDequeRemoveFirstOccurrence() {
+    return new ArrayDeque<>().remove("foo");
+  }
+
+  Iterator<String> testDequeIterator() {
+    return new ArrayDeque<String>().reversed().descendingIterator();
+  }
+
+  Iterator<String> testDequeDescendingIterator() {
+    return new ArrayDeque<String>().reversed().iterator();
+  }
+}

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

@@ -0,0 +1,51 @@
+package tech.picnic.errorprone.refasterrules;
+
+import com.google.common.collect.ImmutableSet;
+import java.util.ArrayDeque;
+import java.util.Iterator;
+import java.util.LinkedList;
+import tech.picnic.errorprone.refaster.test.RefasterRuleCollectionTestCase;
+
+final class DequeRulesTest implements RefasterRuleCollectionTestCase {
+  void testDequeAddFirst() {
+    new ArrayDeque<String>().addFirst("foo");
+  }
+
+  void testDequeAddLast() {
+    new ArrayDeque<String>().addLast("foo");
+    new LinkedList<String>().add("bar");
+  }
+
+  ImmutableSet<String> testDequeRemoveFirst() {
+    return ImmutableSet.of(
+        new ArrayDeque<String>(0).removeFirst(), new ArrayDeque<String>(1).removeFirst());
+  }
+
+  boolean testDequeOfferLast() {
+    return new ArrayDeque<String>().offerLast("foo");
+  }
+
+  String testDequePollFirst() {
+    return new ArrayDeque<String>().pollFirst();
+  }
+
+  String testDequeGetFirst() {
+    return new ArrayDeque<String>().getFirst();
+  }
+
+  String testDequePeekFirst() {
+    return new ArrayDeque<String>().peekFirst();
+  }
+
+  boolean testDequeRemoveFirstOccurrence() {
+    return new ArrayDeque<>().removeFirstOccurrence("foo");
+  }
+
+  Iterator<String> testDequeIterator() {
+    return new ArrayDeque<String>().iterator();
+  }
+
+  Iterator<String> testDequeDescendingIterator() {
+    return new ArrayDeque<String>().descendingIterator();
+  }
+}