Fix issue #667 and add testcases

json-path/src/main/java/com/jayway/jsonpath/internal/function/text/Length.java

@@ -57,7 +57,7 @@ public class Length implements PathFunction {
                     while (null != tail && null != tail.getNext()) {
                         tail = tail.getNext();
                     }
-                    if (null != tail) {
+                    if (ctx.configuration().jsonProvider().isMap(model) && null != tail) {
                         tail.setNext(new WildcardPathToken());
                     }
                 }

json-path/src/test/java/com/jayway/jsonpath/JsonOrgJsonProviderTest.java

@@ -68,6 +68,14 @@ public class JsonOrgJsonProviderTest extends BaseTest {
         assertThat(result).isEqualTo(4);
     }
 
+    @Test
+    public void read_book_length_using_translated_query_with_filter() {
+        Object result = using(Configuration.defaultConfiguration())
+                .parse(JSON_BOOK_STORE_DOCUMENT)
+                .read("$..[?(@.category == \"fiction\")].length()");
+        assertThat(result).isEqualTo(3);
+    }
+
     @Test
     public void read_book_length() {
         Object result = using(Configuration.defaultConfiguration())
@@ -76,4 +84,71 @@ public class JsonOrgJsonProviderTest extends BaseTest {
         assertThat(result).isEqualTo(4);
     }
 
+    @Test
+    public void test(){
+        String json = "[\n" +
+                "    {\n" +
+                "        \"author\": \"Nigel Rees\",\n" +
+                "        \"category\": \"reference\",\n" +
+                "        \"price\": 8.95,\n" +
+                "        \"title\": \"Sayings of the Century\"\n" +
+                "    },\n" +
+                "    {\n" +
+                "        \"author\": \"Evelyn Waugh\",\n" +
+                "        \"category\": \"fiction\",\n" +
+                "        \"price\": 12.99,\n" +
+                "        \"title\": \"Sword of Honour\"\n" +
+                "    },\n" +
+                "    {\n" +
+                "        \"author\": \"Herman Melville\",\n" +
+                "        \"category\": \"fiction\",\n" +
+                "        \"isbn\": \"0-553-21311-3\",\n" +
+                "        \"price\": 8.99,\n" +
+                "        \"title\": \"Moby Dick\"\n" +
+                "    },\n" +
+                "    {\n" +
+                "        \"author\": \"J. R. R. Tolkien\",\n" +
+                "        \"category\": \"fiction\",\n" +
+                "        \"isbn\": \"0-395-19395-8\",\n" +
+                "        \"price\": 22.99,\n" +
+                "        \"title\": \"The Lord of the Rings\"\n" +
+                "    }\n" +
+                "]";
+        Object result = JsonPath.read(json,"$..[?(@.price < 10)].length()");
+        assertThat(result).isEqualTo(2);
+    }
+
+    @Test
+    public void test2(){
+        String json = "[\n" +
+                "    {\n" +
+                "        \"author\": \"Nigel Rees\",\n" +
+                "        \"category\": \"reference\",\n" +
+                "        \"price\": 8.95,\n" +
+                "        \"title\": \"Sayings of the Century\"\n" +
+                "    },\n" +
+                "    {\n" +
+                "        \"author\": \"Evelyn Waugh\",\n" +
+                "        \"category\": \"fiction\",\n" +
+                "        \"price\": 12.99,\n" +
+                "        \"title\": \"Sword of Honour\"\n" +
+                "    },\n" +
+                "    {\n" +
+                "        \"author\": \"Herman Melville\",\n" +
+                "        \"category\": \"fiction\",\n" +
+                "        \"isbn\": \"0-553-21311-3\",\n" +
+                "        \"price\": 8.99,\n" +
+                "        \"title\": \"Moby Dick\"\n" +
+                "    },\n" +
+                "    {\n" +
+                "        \"author\": \"J. R. R. Tolkien\",\n" +
+                "        \"category\": \"fiction\",\n" +
+                "        \"isbn\": \"0-395-19395-8\",\n" +
+                "        \"price\": 22.99,\n" +
+                "        \"title\": \"The Lord of the Rings\"\n" +
+                "    }\n" +
+                "]";
+        Object result = JsonPath.read(json,"$..[?(@.price == 22.99)].length()");
+        assertThat(result).isEqualTo(1);
+    }
 }