Moved the CSRF token client over into main commons code (#5471)

app/src/test/kotlin/fr/free/nrw/commons/MockWebServerTest.java

@@ -0,0 +1,111 @@
+package fr.free.nrw.commons;
+
+import androidx.annotation.NonNull;
+import java.util.List;
+import java.util.concurrent.AbstractExecutorService;
+import java.util.concurrent.Executor;
+import java.util.concurrent.TimeUnit;
+import okhttp3.Dispatcher;
+import okhttp3.OkHttpClient;
+import okhttp3.mockwebserver.MockResponse;
+import org.junit.After;
+import org.junit.Before;
+import org.junit.runner.RunWith;
+import org.robolectric.RobolectricTestRunner;
+import org.wikipedia.AppAdapter;
+import org.wikipedia.dataclient.Service;
+import org.wikipedia.dataclient.WikiSite;
+import org.wikipedia.json.GsonUtil;
+import retrofit2.Retrofit;
+import retrofit2.converter.gson.GsonConverterFactory;
+
+@RunWith(RobolectricTestRunner.class)
+public abstract class MockWebServerTest {
+    private OkHttpClient okHttpClient;
+    private final TestWebServer server = new TestWebServer();
+
+    @Before public void setUp() throws Throwable {
+        AppAdapter.set(new TestAppAdapter());
+        OkHttpClient.Builder builder = AppAdapter.get().getOkHttpClient(new WikiSite(Service.WIKIPEDIA_URL)).newBuilder();
+        okHttpClient = builder.dispatcher(new Dispatcher(new ImmediateExecutorService())).build();
+        server.setUp();
+    }
+
+    @After public void tearDown() throws Throwable {
+        server.tearDown();
+    }
+
+    @NonNull protected TestWebServer server() {
+        return server;
+    }
+
+    protected void enqueueFromFile(@NonNull String filename) throws Throwable {
+        String json = TestFileUtil.readRawFile(filename);
+        server.enqueue(json);
+    }
+
+    protected void enqueue404() {
+        final int code = 404;
+        server.enqueue(new MockResponse().setResponseCode(code).setBody("Not Found"));
+    }
+
+    protected void enqueueMalformed() {
+        server.enqueue("(╯°□°）╯︵ ┻━┻");
+    }
+
+    protected void enqueueEmptyJson() {
+        server.enqueue(new MockResponse().setBody("{}"));
+    }
+
+    @NonNull protected OkHttpClient okHttpClient() {
+        return okHttpClient;
+    }
+
+    @NonNull protected <T> T service(Class<T> clazz) {
+        return service(clazz, server().getUrl());
+    }
+
+    @NonNull protected <T> T service(Class<T> clazz, @NonNull String url) {
+        return new Retrofit.Builder()
+                .baseUrl(url)
+                .callbackExecutor(new ImmediateExecutor())
+                .client(okHttpClient)
+                .addConverterFactory(GsonConverterFactory.create(GsonUtil.getDefaultGson()))
+                .build()
+                .create(clazz);
+    }
+
+    public final class ImmediateExecutorService extends AbstractExecutorService {
+        @Override public void shutdown() {
+            throw new UnsupportedOperationException();
+        }
+
+        @NonNull @Override public List<Runnable> shutdownNow() {
+            throw new UnsupportedOperationException();
+        }
+
+        @Override public boolean isShutdown() {
+            throw new UnsupportedOperationException();
+        }
+
+        @Override public boolean isTerminated() {
+            throw new UnsupportedOperationException();
+        }
+
+        @Override public boolean awaitTermination(long l, @NonNull TimeUnit timeUnit)
+            throws InterruptedException {
+            throw new UnsupportedOperationException();
+        }
+
+        @Override public void execute(@NonNull Runnable runnable) {
+            runnable.run();
+        }
+    }
+
+    public class ImmediateExecutor implements Executor {
+        @Override
+        public void execute(@NonNull Runnable runnable) {
+            runnable.run();
+        }
+    }
+}