Handle the NullPointerException when looking up a resource value of…

… a `DynamicRefTable` when the data type is invalid. Given that the function has the return type as error code, 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 · fb268ae · fb268ae
1 parent 3cdc3f1
commit fb268ae
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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);
+  }
+}