Make the usage of protoSources a little less confusing

README.md

@@ -26,10 +26,14 @@ protocDep = 'com.google.protobuf:protoc:3.0.0-alpha-2'
 
 // Optional - the location of proto files for each Java sourceSet, defaults to
 // fileTree('src/<sourceSetName>/proto') {include '**/*.proto'}
-protoSources('main').add fileTree('src/main/protobuf') {
+protoSources 'main', fileTree('src/main/protobuf') {
+  include '**/*.proto'
+  include '**/*.protodevel'
+}
+protoSources 'main', fileTree('src/main/protocolbuffers') {
   include '**/*.proto'
 }
-protoSources('test').add fileTree('src/test/protobuf') {
+protoSources 'test', fileTree('src/test/protobuf') {
   include '**/*.protodevel'
 }
 

src/main/groovy/com/google/protobuf/gradle/ProtobufConvention.groovy

@@ -58,14 +58,14 @@ class ProtobufConvention {
      *
      * <p>Example:
      * <pre>
-     * protoSources('main').add fileTree('src/main/protobuf') {
+     * protoSources 'main', fileTree('src/main/protobuf') {
      *   include '**' + '/' + '*.proto'
      *   exclude 'src/main/protobuf/excluded.proto'
      * }
      * </pre>
      */
-    def List<?> protoSources(String sourceSetName) {
-      return protoSources.get(sourceSetName)
+    def protoSources(String sourceSetName, Object sourceFiles) {
+      protoSources.get(sourceSetName).add(sourceFiles)
     }
 
     /**

testProjectCustomProtoDir/build.gradle

@@ -22,13 +22,17 @@ dependencies {
 protocDep = 'com.google.protobuf:protoc:2.6.1'
 
 // Override the default 'src/main/proto' directory
-protoSources('main').add fileTree('src/main/protobuf') {
+// You can specify multiple sources for a sourceSet
+protoSources 'main', fileTree('src/main/protobuf') {
     include '**/*.proto'
     include '**/*.protodevel'
 }
+protoSources 'main', fileTree('src/main/protocolbuffers') {
+    include '**/*.proto'
+}
 
 // Override the default 'src/test/proto' directory
-protoSources('test').add fileTree('src/test/protocolbuffers') {
+protoSources 'test', fileTree('src/test/protocolbuffers') {
     include '**/*.proto'
 }
 

testProjectCustomProtoDir/src/main/java/Foo.java

@@ -14,6 +14,9 @@ public static List<MessageLite> getDefaultInstances() {
     // from src/main/protobuf/sample.proto (java_multiple_files == true, thus no outter class)
     list.add(com.example.tutorial.Msg.getDefaultInstance());
     list.add(com.example.tutorial.SecondMsg.getDefaultInstance());
+    // from src/main/protocolbuffers/more.proto
+    list.add(More.MoreMsg.getDefaultInstance());
+    list.add(More.Foo.getDefaultInstance());
     return list;
   }
 }

testProjectCustomProtoDir/src/main/protocolbuffers/more.proto

@@ -0,0 +1,7 @@
+message MoreMsg {
+    optional string bar = 1;
+}
+
+message Foo {
+    optional string stuff = 1;
+}

testProjectCustomProtoDir/src/test/java/FooTest.java

@@ -2,7 +2,7 @@
 public class FooTest {
   @org.junit.Test
   public void testMainProtos() {
-    org.junit.Assert.assertEquals(6, Foo.getDefaultInstances().size());
+    org.junit.Assert.assertEquals(8, Foo.getDefaultInstances().size());
   }
 
   @org.junit.Test