Add recipe to simplify AssertJ SequencedCollection assertions

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

@@ -0,0 +1,89 @@
+/*
+ * Copyright 2025 the original author or authors.
+ * <p>
+ * Licensed under the Moderne Source Available License (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ * <p>
+ * https://docs.moderne.io/licensing/moderne-source-available-license
+ * <p>
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.openrewrite.java.testing.assertj;
+
+import org.openrewrite.ExecutionContext;
+import org.openrewrite.Preconditions;
+import org.openrewrite.Recipe;
+import org.openrewrite.TreeVisitor;
+import org.openrewrite.java.JavaIsoVisitor;
+import org.openrewrite.java.JavaParser;
+import org.openrewrite.java.JavaTemplate;
+import org.openrewrite.java.MethodMatcher;
+import org.openrewrite.java.search.UsesMethod;
+import org.openrewrite.java.tree.Expression;
+import org.openrewrite.java.tree.J;
+
+public class SimplifySequencedCollectionAssertions extends Recipe {
+
+    private static final MethodMatcher ASSERT_THAT_MATCHER = new MethodMatcher("org.assertj.core.api.Assertions assertThat(..)");
+    private static final MethodMatcher GET_FIRST_MATCHER = new MethodMatcher("java.util.* getFirst()");
+    private static final MethodMatcher GET_LAST_MATCHER = new MethodMatcher("java.util.* getLast()");
+
+    @Override
+    public String getDisplayName() {
+        return "Simplify AssertJ assertions on SequencedCollection";
+    }
+
+    @Override
+    public String getDescription() {
+        return "Simplify AssertJ assertions on SequencedCollection by using dedicated assertion methods. " +
+                "For example, `assertThat(sequencedCollection.getLast())` can be simplified to `assertThat(sequencedCollection).last()`.";
+    }
+
+    @Override
+    public TreeVisitor<?, ExecutionContext> getVisitor() {
+        return Preconditions.check(
+                Preconditions.or(
+                        new UsesMethod<>(GET_FIRST_MATCHER),
+                        new UsesMethod<>(GET_LAST_MATCHER)
+                ),
+                new JavaIsoVisitor<ExecutionContext>() {
+                    @Override
+                    public J.MethodInvocation visitMethodInvocation(J.MethodInvocation method, ExecutionContext ctx) {
+                        J.MethodInvocation mi = super.visitMethodInvocation(method, ctx);
+
+                        // Check if this is an assertThat call
+                        if (!ASSERT_THAT_MATCHER.matches(mi) || mi.getArguments().size() != 1) {
+                            return mi;
+                        }
+
+                        // Check if the argument is a method invocation
+                        Expression arg = mi.getArguments().get(0);
+                        if (arg instanceof J.MethodInvocation) {
+                            // Check if the method is getFirst() or getLast() on a SequencedCollection
+                            if (GET_FIRST_MATCHER.matches(arg)) {
+                                return assertThat(mi, (J.MethodInvocation) arg, "first", ctx);
+                            }
+                            if (GET_LAST_MATCHER.matches(arg)) {
+                                return assertThat(mi, (J.MethodInvocation) arg, "last", ctx);
+                            }
+                        }
+
+                        return mi;
+                    }
+
+                    private J.MethodInvocation assertThat(J.MethodInvocation mi, J.MethodInvocation argMethod, String dedicatedAssertion, ExecutionContext ctx) {
+                        return JavaTemplate.builder("assertThat(#{any(java.lang.Iterable)})." + dedicatedAssertion + "()")
+                                .staticImports("org.assertj.core.api.Assertions.assertThat")
+                                .javaParser(JavaParser.fromJavaVersion().classpathFromResources(ctx, "assertj-core-3"))
+                                .build()
+                                .apply(getCursor(), mi.getCoordinates().replace(), argMethod.getSelect());
+                    }
+                }
+        );
+    }
+}

src/main/resources/META-INF/rewrite/assertj.yml

@@ -47,6 +47,7 @@ recipeList:
   - org.openrewrite.java.testing.assertj.SimplifyChainedAssertJAssertions
   - org.openrewrite.java.testing.assertj.SimplifyAssertJAssertions
   - org.openrewrite.java.testing.assertj.SimplifyHasSizeAssertion
+  - org.openrewrite.java.testing.assertj.SimplifySequencedCollectionAssertions
 
   - tech.picnic.errorprone.refasterrules.AssertJBigDecimalRulesRecipes
   - org.openrewrite.java.testing.assertj.AssertJBigIntegerRulesRecipes

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

@@ -0,0 +1,138 @@
+/*
+ * Copyright 2025 the original author or authors.
+ * <p>
+ * Licensed under the Moderne Source Available License (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ * <p>
+ * https://docs.moderne.io/licensing/moderne-source-available-license
+ * <p>
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.openrewrite.java.testing.assertj;
+
+import org.junit.jupiter.api.Test;
+import org.openrewrite.DocumentExample;
+import org.openrewrite.InMemoryExecutionContext;
+import org.openrewrite.java.JavaParser;
+import org.openrewrite.test.RecipeSpec;
+import org.openrewrite.test.RewriteTest;
+
+import static org.openrewrite.java.Assertions.java;
+
+class SimplifySequencedCollectionAssertionsTest implements RewriteTest {
+    @Override
+    public void defaults(RecipeSpec spec) {
+        spec
+          .parser(JavaParser.fromJavaVersion().classpathFromResources(new InMemoryExecutionContext(), "assertj-core-3"))
+          .recipe(new SimplifySequencedCollectionAssertions());
+    }
+
+    @DocumentExample
+    @Test
+    void getLast() {
+        rewriteRun(
+          //language=java
+          java(
+            """
+              import java.util.List;
+
+              import static org.assertj.core.api.Assertions.assertThat;
+
+              class MyTest {
+                  void testMethod() {
+                      List<String> list = List.of("a", "b", "c");
+                      assertThat(list.getLast()).isEqualTo("c");
+                  }
+              }
+              """,
+            """
+              import java.util.List;
+
+              import static org.assertj.core.api.Assertions.assertThat;
+
+              class MyTest {
+                  void testMethod() {
+                      List<String> list = List.of("a", "b", "c");
+                      assertThat(list).last().isEqualTo("c");
+                  }
+              }
+              """
+          )
+        );
+    }
+
+    @Test
+    void getFirst() {
+        rewriteRun(
+          //language=java
+          java(
+            """
+              import java.util.List;
+
+              import static org.assertj.core.api.Assertions.assertThat;
+
+              class MyTest {
+                  void testMethod() {
+                      List<String> list = List.of("a", "b", "c");
+                      assertThat(list.getFirst()).isEqualTo("a");
+                  }
+              }
+              """,
+            """
+              import java.util.List;
+
+              import static org.assertj.core.api.Assertions.assertThat;
+
+              class MyTest {
+                  void testMethod() {
+                      List<String> list = List.of("a", "b", "c");
+                      assertThat(list).first().isEqualTo("a");
+                  }
+              }
+              """
+          )
+        );
+    }
+
+    @Test
+    void withDifferentAssertions() {
+        rewriteRun(
+          //language=java
+          java(
+            """
+              import java.util.List;
+
+              import static org.assertj.core.api.Assertions.assertThat;
+
+              class MyTest {
+                  void testMethod() {
+                      List<String> list = List.of("a", "b", "c");
+                      assertThat(list.getLast()).isNotNull();
+                      assertThat(list.getFirst()).isNotEmpty();
+                      assertThat(list.getLast()).contains("c");
+                  }
+              }
+              """,
+            """
+              import java.util.List;
+
+              import static org.assertj.core.api.Assertions.assertThat;
+
+              class MyTest {
+                  void testMethod() {
+                      List<String> list = List.of("a", "b", "c");
+                      assertThat(list).last().isNotNull();
+                      assertThat(list).first().isNotEmpty();
+                      assertThat(list).last().contains("c");
+                  }
+              }
+              """
+          )
+        );
+    }
+}