Recover from Harmony Type.toString() bug, which affects Android Froyo:

cpovirk · cpovirk · commit 79a6e1c92664 · 2014-05-08T12:01:38.000-04:00
http://stackoverflow.com/a/8169250/28465
diff --git a/guava-testlib/src/com/google/common/testing/NullPointerTester.java b/guava-testlib/src/com/google/common/testing/NullPointerTester.java
@@ -354,6 +354,17 @@ private void testParameter(Object instance, Invokable<?, ?> invokable,
     }
   }
 
+  private static String bestAvailableString(
+      TypeToken type, int position, Invokable<?, ?> invokable) {
+    checkNotNull(type);
+    try {
+      return type.toString();
+    } catch (NullPointerException androidBug6636) {
+      // http://stackoverflow.com/a/8169250/28465
+      return String.format("unknown (arg %s of %s)", position, invokable);
+    }
+  }
+
   private Object[] buildParamList(Invokable<?, ?> invokable, int indexOfParamToSetToNull) {
     ImmutableList<Parameter> params = invokable.getParameters();
     Object[] args = new Object[params.size()];
@@ -364,7 +375,7 @@ private Object[] buildParamList(Invokable<?, ?> invokable, int indexOfParamToSet
         args[i] = getDefaultValue(param.getType());
         Assert.assertTrue(
             "Can't find or create a sample instance for type '"
-                + param.getType()
+                + bestAvailableString(param.getType(), i, invokable)
                 + "'; please provide one using NullPointerTester.setDefault()",
             args[i] != null || isNullable(param));
       }
