robolectric/src/main/java/org/robolectric/plugins/PackagePropertiesLoader.java
public Properties getConfigProperties(@Nonnull String packageName) {
    return cache.computeIfAbsent(packageName, s -> {
      StringBuilder buf = new StringBuilder();
      if (!packageName.isEmpty()) {
        buf.append(packageName.replace('.', '/'));
        buf.append('/');
      }
      buf.append(RobolectricTestRunner.CONFIG_PROPERTIES);
      final String resourceName = buf.toString();

      try (InputStream resourceAsStream = getResourceAsStream(resourceName)) {
        if (resourceAsStream == null) {
          return null;
        }
        Properties properties = new Properties();
        properties.load(resourceAsStream);
        return properties;
      } catch (IOException e) {
        throw new RuntimeException(e);
      }
    });
  }
public Properties getConfigProperties(@Nonnull String packageName) {
    return cache.computeIfAbsent(packageName, s -> {
      StringBuilder buf = new StringBuilder();
      if (!packageName.isEmpty()) {
        buf.append(packageName.replace('.', '/'));
        buf.append('/');
      }
      buf.append(RobolectricTestRunner.CONFIG_PROPERTIES);
      final String resourceName = buf.toString();

      try (InputStream resourceAsStream = getResourceAsStream(resourceName)) {
        if (resourceAsStream == null) {
          return null;
        }
        Properties properties = new Properties();
        properties.load(resourceAsStream);
        return properties;
      } catch (IOException e) {
        throw new RuntimeException(e);
      }
    });
  }
Return a {@link Properties} file for the given package name, or {@code null} if none is
available.

@since 3.2