Improve tests for WebClient

error-prone-contrib/pom.xml

@@ -171,6 +171,11 @@
             <artifactId>spring-context</artifactId>
             <scope>test</scope>
         </dependency>
+        <dependency>
+            <groupId>org.springframework</groupId>
+            <artifactId>spring-core</artifactId>
+            <scope>provided</scope>
+        </dependency>
         <dependency>
             <groupId>org.springframework</groupId>
             <artifactId>spring-test</artifactId>

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

@@ -1,12 +1,19 @@
 package tech.picnic.errorprone.refastertemplates;
 
+import static java.util.function.Function.identity;
 import static org.springframework.web.reactive.function.BodyInserters.fromValue;
 
+import com.google.errorprone.refaster.Refaster;
 import com.google.errorprone.refaster.annotation.AfterTemplate;
 import com.google.errorprone.refaster.annotation.BeforeTemplate;
+import java.util.Collection;
+import org.springframework.core.ParameterizedTypeReference;
 import org.springframework.test.web.reactive.server.WebTestClient;
+import org.springframework.web.reactive.function.client.WebClient;
 import org.springframework.web.reactive.function.client.WebClient.RequestBodySpec;
 import org.springframework.web.reactive.function.client.WebClient.RequestHeadersSpec;
+import reactor.core.publisher.Flux;
+import reactor.core.publisher.Mono;
 
 /**
  * Refaster templates related to expressions dealing with {@link
@@ -33,4 +40,54 @@ final class WebClientTemplates {
       return requestBodySpec.bodyValue(value);
     }
   }
+
+  static final class RetrieveArray<T> {
+    @BeforeTemplate
+    Flux<T> before(WebClient.ResponseSpec responseSpec) {
+      return responseSpec.bodyToMono(Refaster.<T[]>clazz()).flux().flatMap(Flux::fromArray);
+    }
+
+    @AfterTemplate
+    Flux<T> after(WebClient.ResponseSpec responseSpec) {
+      return responseSpec.bodyToFlux(Refaster.<T>clazz());
+    }
+  }
+
+  static final class RetrieveParameterizedTypeReference<T> {
+    @BeforeTemplate
+    Flux<T> before(
+        WebClient.ResponseSpec responseSpec,
+        ParameterizedTypeReference<? extends Collection<T>> clazz) {
+      return responseSpec.bodyToMono(clazz).flux().flatMapIterable(identity());
+    }
+
+    @AfterTemplate
+    Flux<T> after(WebClient.ResponseSpec responseSpec) {
+      return responseSpec.bodyToFlux(Refaster.<T>clazz());
+    }
+  }
+
+  static final class RetrieveSingle<T> {
+    @BeforeTemplate
+    Mono<T> before(Mono<T> mono, Class<T> clazz) {
+      return mono.flux().single();
+    }
+
+    @AfterTemplate
+    Mono<T> after(Mono<T> mono, Class<T> clazz) {
+      return mono.single();
+    }
+  }
+
+  static final class RetrieveSingleOrEmpty<T> {
+    @BeforeTemplate
+    Mono<T> before(Mono<T> mono, Class<T> clazz) {
+      return mono.flux().singleOrEmpty();
+    }
+
+    @AfterTemplate
+    Mono<T> after(Mono<T> mono) {
+      return mono;
+    }
+  }
 }

error-prone-contrib/src/test/resources/tech/picnic/errorprone/bugpatterns/WebClientTemplatesTestInput.java

@@ -1,15 +1,25 @@
 package tech.picnic.errorprone.bugpatterns;
 
+import static java.util.function.Function.identity;
 import static org.springframework.web.reactive.function.BodyInserters.fromValue;
 
+import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableSet;
+import org.springframework.core.ParameterizedTypeReference;
 import org.springframework.test.web.reactive.server.WebTestClient;
 import org.springframework.web.reactive.function.client.WebClient;
+import reactor.core.publisher.Flux;
+import reactor.core.publisher.Mono;
 
 final class WebClientTemplatesTest implements RefasterTemplateTestCase {
   @Override
   public ImmutableSet<?> elidedTypesAndStaticImports() {
-    return ImmutableSet.of(fromValue(""));
+    return ImmutableSet.of(
+        fromValue(""),
+        identity(),
+        Flux.class,
+        ImmutableList.class,
+        ParameterizedTypeReference.class);
   }
 
   ImmutableSet<?> testBodyValue() {
@@ -17,4 +27,30 @@ final class WebClientTemplatesTest implements RefasterTemplateTestCase {
         WebClient.create("foo").post().body(fromValue("bar")),
         WebTestClient.bindToServer().build().post().body(fromValue("bar")));
   }
+
+  public void testBodyToFluxValue() {
+    WebClient.create("foo")
+        .get()
+        .retrieve()
+        .bodyToMono(Integer[].class)
+        .flux()
+        .flatMap(Flux::fromArray);
+  }
+
+  public void testOther() {
+    WebClient.create("foo")
+        .get()
+        .retrieve()
+        .bodyToMono(new ParameterizedTypeReference<ImmutableList<String>>() {})
+        .flux()
+        .flatMapIterable(identity());
+  }
+
+  public void testCase3() {
+    Mono.empty().flux().single();
+  }
+
+  public void testCase4() {
+    Mono.empty().flux().singleOrEmpty();
+  }
 }

error-prone-contrib/src/test/resources/tech/picnic/errorprone/bugpatterns/WebClientTemplatesTestOutput.java

@@ -1,15 +1,25 @@
 package tech.picnic.errorprone.bugpatterns;
 
+import static java.util.function.Function.identity;
 import static org.springframework.web.reactive.function.BodyInserters.fromValue;
 
+import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableSet;
+import org.springframework.core.ParameterizedTypeReference;
 import org.springframework.test.web.reactive.server.WebTestClient;
 import org.springframework.web.reactive.function.client.WebClient;
+import reactor.core.publisher.Flux;
+import reactor.core.publisher.Mono;
 
 final class WebClientTemplatesTest implements RefasterTemplateTestCase {
   @Override
   public ImmutableSet<?> elidedTypesAndStaticImports() {
-    return ImmutableSet.of(fromValue(""));
+    return ImmutableSet.of(
+        fromValue(""),
+        identity(),
+        Flux.class,
+        ImmutableList.class,
+        ParameterizedTypeReference.class);
   }
 
   ImmutableSet<?> testBodyValue() {
@@ -17,4 +27,20 @@ final class WebClientTemplatesTest implements RefasterTemplateTestCase {
         WebClient.create("foo").post().bodyValue("bar"),
         WebTestClient.bindToServer().build().post().bodyValue("bar"));
   }
+
+  public void testBodyToFluxValue() {
+    WebClient.create("foo").get().retrieve().bodyToFlux(Integer.class);
+  }
+
+  public void testOther() {
+    WebClient.create("foo").get().retrieve().bodyToFlux(String.class);
+  }
+
+  public void testCase3() {
+    Mono.empty().single();
+  }
+
+  public void testCase4() {
+    Mono.empty();
+  }
 }