assertFalse(queryFieldConfig.isSortField("anyfield"));
        assertFalse(queryFieldConfig.isSortField(""));
        assertFalse(queryFieldConfig.isSortField(null));
    }

    public void test_isFacetField_withEmptyArray() {
        queryFieldConfig.setFacetFields(new String[] {});

        assertFalse(queryFieldConfig.isFacetField("anyfield"));
        assertFalse(queryFieldConfig.isFacetField(""));

    }

    /**
     * Tests the writeDataWireFormat method.
     */
    @Test
    void testWriteDataWireFormat() {
        // Given
        Trans2QueryPathInformation trans = new Trans2QueryPathInformation("anyfile.txt", 0);
        byte[] dst = new byte[10];

        // When
        int bytesWritten = trans.writeDataWireFormat(dst, 0);

        // Then
        assertEquals(0, bytesWritten, "Should write 0 bytes.");
    }

          continue
        }

        val value = value(i)
        if (result == null) {
          result = TreeSet(String.CASE_INSENSITIVE_ORDER)
        }
        for (varyField in value.split(',')) {
          result.add(varyField.trim())
        }
      }
      return result ?: emptySet()
    }

    /**
     * Returns the subset of the headers in this's request that impact the content of this's body.