Merge pull request #2885 from square/jakew/reified-create/2018-09-11

Add reified create extension for Kotlin

retrofit/pom.xml

@@ -75,6 +75,26 @@
 
   <build>
     <plugins>
+      <plugin>
+        <groupId>org.jetbrains.kotlin</groupId>
+        <artifactId>kotlin-maven-plugin</artifactId>
+        <executions>
+          <execution>
+            <id>compile</id>
+            <phase>process-sources</phase>
+            <goals>
+              <goal>compile</goal>
+            </goals>
+          </execution>
+          <execution>
+            <id>test-compile</id>
+            <phase>test-compile</phase>
+            <goals>
+              <goal>test-compile</goal>
+            </goals>
+          </execution>
+        </executions>
+      </plugin>
       <plugin>
         <groupId>org.apache.maven.plugins</groupId>
         <artifactId>maven-jar-plugin</artifactId>

retrofit/src/main/java/retrofit2/KotlinExtensions.kt

+/*
+ * Copyright (C) 2018 Square, Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * 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.
+ */
+
+// Hide the class from Java consumers.
+@file:JvmName("-KotlinExtensions")
+
+package retrofit2
+
+inline fun <reified T> Retrofit.create(): T = create(T::class.java)

retrofit/src/main/resources/META-INF/proguard/retrofit2.pro

@@ -14,3 +14,6 @@
 
 # Guarded by a NoClassDefFoundError try/catch and only used when on the classpath.
 -dontwarn kotlin.Unit
+
+# Top-level functions that can only be used by Kotlin.
+-dontwarn retrofit2.-KotlinExtensions

retrofit/src/test/java/retrofit2/KotlinExtensionsTest.kt

+/*
+ * Copyright (C) 2018 Square, Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * 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 retrofit2
+
+import okhttp3.mockwebserver.MockWebServer
+import org.junit.Assert.assertNotNull
+import org.junit.Rule
+import org.junit.Test
+
+class KotlinExtensionsTest {
+  @get:Rule val server = MockWebServer()
+
+  interface Empty
+
+  @Test fun reifiedCreate() {
+    val retrofit = Retrofit.Builder()
+        .baseUrl(server.url("/"))
+        .build()
+
+    assertNotNull(retrofit.create<Empty>())
+  }
+}