From f4ab9b4e7cd7f751a3fe5fcfe291349d975e8074 Mon Sep 17 00:00:00 2001
From: Phil Werli <phil.werli@teampicnic.com>
Date: Thu, 11 Apr 2024 20:38:49 +0200
Subject: [PATCH] Introduce `StepVerifierLastStepVerifyErrorSatisfiesAssertJ`
 Refaster rule

---
 .../refasterrules/ReactorRules.java           | 25 +++++++++++++++++++
 .../refasterrules/ReactorRulesTestInput.java  | 19 ++++++++++++++
 .../refasterrules/ReactorRulesTestOutput.java | 15 +++++++++++
 3 files changed, 59 insertions(+)

diff --git a/error-prone-contrib/src/main/java/tech/picnic/errorprone/refasterrules/ReactorRules.java b/error-prone-contrib/src/main/java/tech/picnic/errorprone/refasterrules/ReactorRules.java
index bc7f29fc8eb..df5559ec8e2 100644
--- a/error-prone-contrib/src/main/java/tech/picnic/errorprone/refasterrules/ReactorRules.java
+++ b/error-prone-contrib/src/main/java/tech/picnic/errorprone/refasterrules/ReactorRules.java
@@ -41,6 +41,7 @@
 import java.util.function.Predicate;
 import java.util.function.Supplier;
 import java.util.stream.Collector;
+import org.assertj.core.api.Assertions;
 import org.jspecify.annotations.Nullable;
 import org.reactivestreams.Publisher;
 import reactor.core.publisher.Flux;
@@ -1928,6 +1929,30 @@ Duration after(StepVerifier.LastStep step, Consumer<Throwable> consumer) {
     }
   }
 
+  /**
+   * Prefer {@link StepVerifier.LastStep#verifyErrorSatisfies(Consumer)} with AssertJ over more
+   * contrived alternatives.
+   */
+  static final class StepVerifierLastStepVerifyErrorSatisfiesAssertJ {
+    @BeforeTemplate
+    void before(StepVerifier.LastStep step, Class<? extends Throwable> clazz, String message) {
+      Refaster.anyOf(
+          step.expectError()
+              .verifyThenAssertThat()
+              .hasOperatorErrorOfType(clazz)
+              .hasOperatorErrorWithMessage(message),
+          step.expectError(clazz).verifyThenAssertThat().hasOperatorErrorWithMessage(message),
+          step.expectErrorMessage(message).verifyThenAssertThat().hasOperatorErrorOfType(clazz));
+    }
+
+    @AfterTemplate
+    @UseImportPolicy(STATIC_IMPORT_ALWAYS)
+    void after(StepVerifier.LastStep step, Class<? extends Throwable> clazz, String message) {
+      step.verifyErrorSatisfies(
+          t -> Assertions.assertThat(t).isInstanceOf(clazz).hasMessage(message));
+    }
+  }
+
   /**
    * Prefer {@link StepVerifier.LastStep#verifyErrorMessage(String)} over more verbose alternatives.
    */
diff --git a/error-prone-contrib/src/test/resources/tech/picnic/errorprone/refasterrules/ReactorRulesTestInput.java b/error-prone-contrib/src/test/resources/tech/picnic/errorprone/refasterrules/ReactorRulesTestInput.java
index b934750af1b..0e5fdaaa6a1 100644
--- a/error-prone-contrib/src/test/resources/tech/picnic/errorprone/refasterrules/ReactorRulesTestInput.java
+++ b/error-prone-contrib/src/test/resources/tech/picnic/errorprone/refasterrules/ReactorRulesTestInput.java
@@ -655,6 +655,25 @@ Duration testStepVerifierLastStepVerifyErrorSatisfies() {
     return Mono.empty().as(StepVerifier::create).expectErrorSatisfies(t -> {}).verify();
   }
 
+  void testStepVerifierLastStepVerifyErrorSatisfiesAssertJ() {
+    Mono.empty()
+        .as(StepVerifier::create)
+        .expectError()
+        .verifyThenAssertThat()
+        .hasOperatorErrorOfType(IllegalStateException.class)
+        .hasOperatorErrorWithMessage("foo");
+    Mono.empty()
+        .as(StepVerifier::create)
+        .expectError(IllegalStateException.class)
+        .verifyThenAssertThat()
+        .hasOperatorErrorWithMessage("bar");
+    Mono.empty()
+        .as(StepVerifier::create)
+        .expectErrorMessage("baz")
+        .verifyThenAssertThat()
+        .hasOperatorErrorOfType(IllegalStateException.class);
+  }
+
   Duration testStepVerifierLastStepVerifyErrorMessage() {
     return Mono.empty().as(StepVerifier::create).expectErrorMessage("foo").verify();
   }
diff --git a/error-prone-contrib/src/test/resources/tech/picnic/errorprone/refasterrules/ReactorRulesTestOutput.java b/error-prone-contrib/src/test/resources/tech/picnic/errorprone/refasterrules/ReactorRulesTestOutput.java
index 1a95d60cdaa..dd50924a2a9 100644
--- a/error-prone-contrib/src/test/resources/tech/picnic/errorprone/refasterrules/ReactorRulesTestOutput.java
+++ b/error-prone-contrib/src/test/resources/tech/picnic/errorprone/refasterrules/ReactorRulesTestOutput.java
@@ -636,6 +636,21 @@ Duration testStepVerifierLastStepVerifyErrorSatisfies() {
     return Mono.empty().as(StepVerifier::create).verifyErrorSatisfies(t -> {});
   }
 
+  void testStepVerifierLastStepVerifyErrorSatisfiesAssertJ() {
+    Mono.empty()
+        .as(StepVerifier::create)
+        .verifyErrorSatisfies(
+            t -> assertThat(t).isInstanceOf(IllegalStateException.class).hasMessage("foo"));
+    Mono.empty()
+        .as(StepVerifier::create)
+        .verifyErrorSatisfies(
+            t -> assertThat(t).isInstanceOf(IllegalStateException.class).hasMessage("bar"));
+    Mono.empty()
+        .as(StepVerifier::create)
+        .verifyErrorSatisfies(
+            t -> assertThat(t).isInstanceOf(IllegalStateException.class).hasMessage("baz"));
+  }
+
   Duration testStepVerifierLastStepVerifyErrorMessage() {
     return Mono.empty().as(StepVerifier::create).verifyErrorMessage("foo");
   }