Handle the NullPointerException when looking up resource value of a…

… `DynamicRefTable` when the data type is invalid. When the data type is invalid, it would make sense to return the corresponding bad code instead of throw an exception. PiperOrigin-RevId: 631829984
robolectric · May 8, 2024 · 7f57909 · 7f57909
1 parent 3cdc3f1
commit 7f57909
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Showing 5 changed files with 65 additions and 4 deletions.
diff --git a/resources/src/main/java/org/robolectric/res/android/CppAssetManager2.java b/resources/src/main/java/org/robolectric/res/android/CppAssetManager2.java
@@ -885,7 +885,10 @@ public ApkAssetsCookie GetResource(int resid, boolean may_be_bag,
     out_value.set(device_value.copy());
 
     // Convert the package ID to the runtime assigned package ID.
-    entry.get().dynamic_ref_table.lookupResourceValue(out_value);
+    int err = entry.get().dynamic_ref_table.lookupResourceValue(out_value);
+    if (err != NO_ERROR) {
+      return K_INVALID_COOKIE;
+    }
 
     out_selected_config.set(new ResTable_config(entry.get().config));
     out_flags.set(entry.get().type_flags);

diff --git a/resources/src/main/java/org/robolectric/res/android/DataType.java b/resources/src/main/java/org/robolectric/res/android/DataType.java
@@ -70,6 +70,8 @@ public static DataType fromCode(int code) {
   }
 
   public static DataType fromCode(byte code) {
-    return Preconditions.checkNotNull(FROM_BYTE.get(code), "Unknown resource type: %s", code);
+    DataType type = FROM_BYTE.get(code);
+    Preconditions.checkArgument(type != null, "Unknown resource type: %s", code);
+    return type;
   }
 }
diff --git a/resources/src/main/java/org/robolectric/res/android/DynamicRefTable.java b/resources/src/main/java/org/robolectric/res/android/DynamicRefTable.java
@@ -1,7 +1,9 @@
 package org.robolectric.res.android;
 
-// transliterated from https://android.googlesource.com/platform/frameworks/base/+/android-9.0.0_r12/include/androidfw/ResourceTypes.h
+// transliterated from
+// https://android.googlesource.com/platform/frameworks/base/+/android-9.0.0_r12/include/androidfw/ResourceTypes.h
 
+import static org.robolectric.res.android.Errors.BAD_TYPE;
 import static org.robolectric.res.android.Errors.NO_ERROR;
 import static org.robolectric.res.android.Errors.UNKNOWN_ERROR;
 import static org.robolectric.res.android.ResTable.APP_PACKAGE_ID;
@@ -145,7 +147,15 @@ int lookupResourceId(Ref<Integer> resId) {
   int lookupResourceValue(Ref<Res_value> value) {
     byte resolvedType = DataType.REFERENCE.code();
     Res_value inValue = value.get();
-    switch (DataType.fromCode(inValue.dataType)) {
+
+    DataType dataType;
+    try {
+      dataType = DataType.fromCode(inValue.dataType);
+    } catch (IllegalArgumentException e) {
+      return BAD_TYPE;
+    }
+
+    switch (dataType) {
       case ATTRIBUTE:
         resolvedType = DataType.ATTRIBUTE.code();
         // fallthrough

diff --git a/resources/src/test/java/org/robolectric/res/android/DataTypeTest.java b/resources/src/test/java/org/robolectric/res/android/DataTypeTest.java
@@ -0,0 +1,23 @@
+package org.robolectric.res.android;
+
+import static com.google.common.truth.Truth.assertThat;
+import static org.junit.Assert.assertThrows;
+
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.junit.runners.JUnit4;
+
+@RunWith(JUnit4.class)
+public final class DataTypeTest {
+
+  @Test
+  public void fromCode_shouldThrowExceptionForInvalidCode() {
+    assertThrows(IllegalArgumentException.class, () -> DataType.fromCode(99));
+  }
+
+  @Test
+  public void fromCode_shouldReturnCorrectDataTypeForValidCode() {
+    assertThat(DataType.fromCode(0)).isEqualTo(DataType.NULL);
+    assertThat(DataType.fromCode(3)).isEqualTo(DataType.STRING);
+  }
+}
diff --git a/resources/src/test/java/org/robolectric/res/android/DynamicRefTableTest.java b/resources/src/test/java/org/robolectric/res/android/DynamicRefTableTest.java
@@ -0,0 +1,23 @@
+package org.robolectric.res.android;
+
+import static com.google.common.truth.Truth.assertThat;
+import static org.robolectric.res.android.Errors.BAD_TYPE;
+
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.junit.runners.JUnit4;
+import org.robolectric.res.android.ResourceTypes.Res_value;
+
+@RunWith(JUnit4.class)
+public final class DynamicRefTableTest {
+
+  private static final Ref<Res_value> RES_VALUE_OF_BAD_TYPE =
+      new Ref<>(new Res_value(/* dataType= */ (byte) 99, /* data= */ 0));
+
+  @Test
+  public void lookupResourceValue_returnsBadTypeIfTypeOutOfEnumRange() {
+    DynamicRefTable pseudoRefTable =
+        new DynamicRefTable(/* packageId= */ (byte) 0, /* appAsLib= */ true);
+    assertThat(pseudoRefTable.lookupResourceValue(RES_VALUE_OF_BAD_TYPE)).isEqualTo(BAD_TYPE);
+  }
+}