add more unit tests orderby field normalization

Author: milaGGL

firebase-firestore/src/test/java/com/google/firebase/firestore/core/QueryTest.java

@@ -627,6 +627,7 @@ public void testImplicitOrderByInMultipleInequality() {
             orderBy(KEY_FIELD_NAME, "asc")),
         baseQuery
             .filter(filter("a", "<", 5))
+            .filter(filter("a", ">=", 5))
             .filter(filter("aa", "<", 5))
             .filter(filter("b", "<", 5))
             .filter(filter("A", "<", 5))
@@ -701,6 +702,47 @@ public void testImplicitOrderByInMultipleInequality() {
                     orFilters(filter("b", ">=", 1), filter("c", "<=", 1)),
                     orFilters(filter("d", "<=", 1), filter("e", "==", 1))))
             .getOrderBy());
+
+    // OrderBy
+    assertEquals(
+        asList(
+            orderBy("z", "asc"),
+            orderBy("a", "asc"),
+            orderBy("b", "asc"),
+            orderBy(KEY_FIELD_NAME, "asc")),
+        baseQuery
+            .filter(filter("b", "<", 5))
+            .filter(filter("a", "<", 5))
+            .filter(filter("z", "<", 5))
+            .orderBy(orderBy("z"))
+            .getOrderBy());
+
+    // last explicit order by direction
+    assertEquals(
+        asList(
+            orderBy("z", "desc"),
+            orderBy("a", "desc"),
+            orderBy("b", "desc"),
+            orderBy(KEY_FIELD_NAME, "desc")),
+        baseQuery
+            .filter(filter("b", "<", 5))
+            .filter(filter("a", "<", 5))
+            .orderBy(orderBy("z", "desc"))
+            .getOrderBy());
+
+    assertEquals(
+        asList(
+            orderBy("z", "desc"),
+            orderBy("c", "asc"),
+            orderBy("a", "asc"),
+            orderBy("b", "asc"),
+            orderBy(KEY_FIELD_NAME, "asc")),
+        baseQuery
+            .filter(filter("b", "<", 5))
+            .filter(filter("a", "<", 5))
+            .orderBy(orderBy("z", "desc"))
+            .orderBy(orderBy("c"))
+            .getOrderBy());
   }
 
   @Test