Plumb customPackage to RClassGenerator and skip empty R classes

Forgot to do this, so we get compiler errors
since it can't find the R class imported under
the requested custom java package.

Also, avoid writing out the top-level R.class
file if there are no symbols. There is a test
that happens to check for this.

--
MOS_MIGRATED_REVID=127888913

3 files changed, 109 insertions, 24 deletions

diff --git a/src/main/java/com/google/devtools/build/lib/rules/android/RClassGeneratorActionBuilder.java b/src/main/java/com/google/devtools/build/lib/rules/android/RClassGeneratorActionBuilder.java
index 973966943b..933790a9c0 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/android/RClassGeneratorActionBuilder.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/android/RClassGeneratorActionBuilder.java
@@ -14,6 +14,7 @@
 package com.google.devtools.build.lib.rules.android;
 
 import com.google.common.base.Function;
+import com.google.common.base.Strings;
 import com.google.common.collect.FluentIterable;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.Iterables;
@@ -27,10 +28,8 @@ import com.google.devtools.build.lib.collect.nestedset.NestedSet;
 import com.google.devtools.build.lib.collect.nestedset.NestedSetBuilder;
 import com.google.devtools.build.lib.collect.nestedset.Order;
 import com.google.devtools.build.lib.rules.android.AndroidResourcesProvider.ResourceContainer;
-
 import java.util.ArrayList;
 import java.util.List;
-
 import javax.annotation.Nullable;
 
 /**
@@ -114,6 +113,9 @@ public class RClassGeneratorActionBuilder {
       builder.addExecPath("--primaryManifest", primary.getManifest());
       inputs.add(primary.getManifest());
     }
+    if (!Strings.isNullOrEmpty(primary.getJavaPackage())) {
+      builder.add("--packageForR").add(primary.getJavaPackage());
+    }
     if (dependencies != null) {
       Iterable<ResourceContainer> depResources = dependencies.getResources();
       if (depResources.iterator().hasNext()) {
diff --git a/src/test/java/com/google/devtools/build/android/RClassGeneratorActionTest.java b/src/test/java/com/google/devtools/build/android/RClassGeneratorActionTest.java
index dd28b3ab54..3b8f72c5cd 100644
--- a/src/test/java/com/google/devtools/build/android/RClassGeneratorActionTest.java
+++ b/src/test/java/com/google/devtools/build/android/RClassGeneratorActionTest.java
@@ -19,12 +19,6 @@ import com.google.common.base.Function;
 import com.google.common.base.Joiner;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.Iterables;
-
-import org.junit.Before;
-import org.junit.Test;
-import org.junit.runner.RunWith;
-import org.junit.runners.JUnit4;
-
 import java.io.File;
 import java.io.IOException;
 import java.nio.charset.StandardCharsets;
@@ -36,6 +30,10 @@ import java.util.Collections;
 import java.util.List;
 import java.util.zip.ZipEntry;
 import java.util.zip.ZipFile;
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.junit.runners.JUnit4;
 
 /**
  * Tests for {@link RClassGeneratorAction}.
@@ -114,20 +112,20 @@ public class RClassGeneratorActionTest {
 
     RClassGeneratorAction.main(
         ImmutableList.<String>of(
-                "--primaryRTxt",
-                binarySymbols.toString(),
-                "--primaryManifest",
-                binaryManifest.toString(),
-                "--libraries",
-                libFooSymbols
-                    + File.pathSeparator
-                    + libFooManifest
-                    + ","
-                    + libBarSymbols
-                    + File.pathSeparator
-                    + libBarManifest,
-                "--classJarOutput",
-                jarPath.toString())
+            "--primaryRTxt",
+            binarySymbols.toString(),
+            "--primaryManifest",
+            binaryManifest.toString(),
+            "--libraries",
+            libFooSymbols
+                + File.pathSeparator
+                + libFooManifest
+                + ","
+                + libBarSymbols
+                + File.pathSeparator
+                + libBarManifest,
+            "--classJarOutput",
+            jarPath.toString())
             .toArray(new String[0]));
 
     assertThat(Files.exists(jarPath)).isTrue();
@@ -215,6 +213,86 @@ public class RClassGeneratorActionTest {
     }
   }
 
+  @Test
+  public void customPackageForR() throws Exception {
+    Path binaryManifest = ManifestBuilder.of(tempDir.resolve("binary"))
+        .createManifest("AndroidManifest.xml", "com.google.app",
+            "<application android:name=\"com.google.app\">",
+            "<activity android:name=\"com.google.foo.activityFoo\" />",
+            "</application>");
+    Path libFooManifest = ManifestBuilder.of(tempDir.resolve("libFoo"))
+        .createManifest("AndroidManifest.xml", "com.google.foo", "");
+
+    Path binarySymbols = createFile("R.txt",
+        "int attr agility 0x7f010000",
+        "int integer maxNotifications 0x7f090000",
+        "int string ok 0x7f100001");
+    Path libFooSymbols = createFile("libFoo.R.txt",
+        "int string ok 0x1");
+    Path jarPath = tempDir.resolve("app_resources.jar");
+    RClassGeneratorAction.main(
+        ImmutableList.<String>of(
+            "--primaryRTxt",
+            binarySymbols.toString(),
+            "--primaryManifest",
+            binaryManifest.toString(),
+            "--packageForR", "com.custom.er",
+            "--libraries",
+            libFooSymbols + File.pathSeparator + libFooManifest,
+            "--classJarOutput",
+            jarPath.toString())
+            .toArray(new String[0]));
+
+    assertThat(Files.exists(jarPath)).isTrue();
+    assertThat(Files.getLastModifiedTime(jarPath)).isEqualTo(FileTime.fromMillis(0));
+
+    try (ZipFile zip = new ZipFile(jarPath.toFile())) {
+      List<? extends ZipEntry> zipEntries = Collections.list(zip.entries());
+      Iterable<String> entries = getZipFilenames(zipEntries);
+      assertThat(entries)
+          .containsExactly(
+              Paths.get("com/google/foo/R$string.class").toString(),
+              Paths.get("com/google/foo/R.class").toString(),
+              Paths.get("com/custom/er/R$attr.class").toString(),
+              Paths.get("com/custom/er/R$integer.class").toString(),
+              Paths.get("com/custom/er/R$string.class").toString(),
+              Paths.get("com/custom/er/R.class").toString(),
+              Paths.get("META-INF/MANIFEST.MF").toString());
+    }
+  }
+
+  @Test
+  public void noSymbolsNoRClass() throws Exception {
+    Path binaryManifest = ManifestBuilder.of(tempDir.resolve("binary"))
+        .createManifest("AndroidManifest.xml", "com.google.app",
+            "<application android:name=\"com.google.app\">",
+            "<activity android:name=\"com.google.foo.activityFoo\" />",
+            "</application>");
+
+    Path binarySymbols = createFile("R.txt", "");
+    Path jarPath = tempDir.resolve("app_resources.jar");
+    RClassGeneratorAction.main(
+        ImmutableList.<String>of(
+            "--primaryRTxt",
+            binarySymbols.toString(),
+            "--primaryManifest",
+            binaryManifest.toString(),
+            "--classJarOutput",
+            jarPath.toString())
+            .toArray(new String[0]));
+
+    assertThat(Files.exists(jarPath)).isTrue();
+    assertThat(Files.getLastModifiedTime(jarPath)).isEqualTo(FileTime.fromMillis(0));
+
+    try (ZipFile zip = new ZipFile(jarPath.toFile())) {
+      List<? extends ZipEntry> zipEntries = Collections.list(zip.entries());
+      Iterable<String> entries = getZipFilenames(zipEntries);
+      assertThat(entries)
+          .containsExactly(
+              Paths.get("META-INF/MANIFEST.MF").toString());
+    }
+  }
+
   private Path createFile(String name, String... contents) throws IOException {
     Path path = tempDir.resolve(name);
     Files.createDirectories(path.getParent());
diff --git a/src/tools/android/java/com/google/devtools/build/android/resources/RClassGenerator.java b/src/tools/android/java/com/google/devtools/build/android/resources/RClassGenerator.java
index be25c0f6fa..8735e9ba8c 100644
--- a/src/tools/android/java/com/google/devtools/build/android/resources/RClassGenerator.java
+++ b/src/tools/android/java/com/google/devtools/build/android/resources/RClassGenerator.java
@@ -109,7 +109,14 @@ public class RClassGenerator {
       packageDir = new File(packageDir, folder);
     }
     File rClassFile = new File(packageDir, SdkConstants.FN_COMPILED_RESOURCE_CLASS);
+    // At least create the outFolder that was requested. However, if there are no symbols, don't
+    // create the R.class and inner class files (no need to have an empty class).
     Files.createParentDirs(rClassFile);
+    Table<String, String, SymbolEntry> symbols = getAllSymbols();
+    if (symbols.isEmpty()) {
+      return;
+    }
+
     String packageWithSlashes = packageName.replaceAll("\\.", "/");
     String rClassName = packageWithSlashes + "/R";
     ClassWriter classWriter = new ClassWriter(ClassWriter.COMPUTE_MAXS);
@@ -119,9 +126,7 @@ public class RClassGenerator {
     classWriter.visitSource(SdkConstants.FN_RESOURCE_CLASS, null);
     writeConstructor(classWriter);
 
-    Table<String, String, SymbolEntry> symbols = getAllSymbols();
     Table<String, String, SymbolEntry> values = getSymbols(symbolValues);
-
     Set<String> rowSet = symbols.rowKeySet();
     List<String> rowList = new ArrayList<>(rowSet);
     Collections.sort(rowList);