Tolerate missing field value in binary's R.txt

The binary's R.txt might not be superset of
symbols in the various library R.txt files.

The R.java writer had tolerated this, as did an
older version of the RClassGen (lost in refactoring).
Bring back the null check.

This can happen if the binary has res overrides that
*remove* symbols. E.g., if noop/res/layout/stats.xml
overrides dev/.../stats.xml, and the noop version
removes elements not needed for production.
Test mocks can do something similar.

--
MOS_MIGRATED_REVID=128989080

1 files changed, 39 insertions, 0 deletions

diff --git a/src/test/java/com/google/devtools/build/android/resources/RClassGeneratorTest.java b/src/test/java/com/google/devtools/build/android/resources/RClassGeneratorTest.java
index 33a75b89ed..0b53d86264 100644
--- a/src/test/java/com/google/devtools/build/android/resources/RClassGeneratorTest.java
+++ b/src/test/java/com/google/devtools/build/android/resources/RClassGeneratorTest.java
@@ -181,6 +181,45 @@ public class RClassGeneratorTest {
   }
 
   @Test
+  public void binaryDropsLibraryFields() throws Exception {
+    boolean finalFields = true;
+    // Test what happens if the binary R.txt is not a strict superset of the
+    // library R.txt (overrides that drop elements).
+    SymbolLoader symbolValues = createSymbolFile("R.txt",
+        "int layout stubbable_activity 0x7f020000");
+    SymbolLoader symbolsInLibrary = createSymbolFile("lib.R.txt",
+        "int id debug_text_field 0x1",
+        "int id debug_text_field2 0x1",
+        "int layout stubbable_activity 0x1");
+    Path out = temp.resolve("classes");
+    Files.createDirectories(out);
+    RClassGenerator writer = RClassGenerator.fromSymbols(out, "com.foo",
+        symbolValues, ImmutableList.of(symbolsInLibrary), finalFields);
+    writer.write();
+
+    Path packageDir = out.resolve("com/foo");
+    checkFilesInPackage(packageDir, "R.class", "R$id.class", "R$layout.class");
+    Class<?> outerClass = checkTopLevelClass(out,
+        "com.foo.R",
+        "com.foo.R$id",
+        "com.foo.R$layout");
+    checkInnerClass(out,
+        "com.foo.R$id",
+        outerClass,
+        ImmutableMap.<String, Integer>of(),
+        ImmutableMap.<String, List<Integer>>of(),
+        finalFields
+    );
+    checkInnerClass(out,
+        "com.foo.R$layout",
+        outerClass,
+        ImmutableMap.of("stubbable_activity", 0x7f020000),
+        ImmutableMap.<String, List<Integer>>of(),
+        finalFields
+    );
+  }
+
+  @Test
   public void intArraysFinal() throws Exception {
     checkIntArrays(true);
   }