Implement NSPredicate-based query (#531)

*   implement queryFilteredUsingPredicate in FIRQuery;
*   add unit test and integration test for queryFilteredUsingPredicate;
*   project change of adding the FIRQueryTests.m file;
*   refactoring queryFilteredUsingPredicate to split logic into two helpers;

1 files changed, 13 insertions, 0 deletions

diff --git a/Firestore/Source/Public/FIRQuery.h b/Firestore/Source/Public/FIRQuery.h
index 0f3aeed..ff15ac6 100644
--- a/Firestore/Source/Public/FIRQuery.h
+++ b/Firestore/Source/Public/FIRQuery.h
@@ -256,6 +256,19 @@ NS_SWIFT_NAME(Query)
            isGreaterThanOrEqualTo:(id)value NS_SWIFT_NAME(whereField(_:isGreaterThanOrEqualTo:));
 // clang-format on
 
+/**
+ * Creates and returns a new `FIRQuery` with the additional filter that documents must
+ * satisfy the specified predicate.
+ *
+ * @param predicate The predicate the document must satisfy. Can be either comparison
+ *     or compound of comparison. In particular, block-based predicate is not supported.
+ *
+ * @return The created `FIRQuery`.
+ */
+// clang-format off
+- (FIRQuery *)queryFilteredUsingPredicate:(NSPredicate *)predicate NS_SWIFT_NAME(filter(using:));
+// clang-format on
+
 #pragma mark - Sorting Data
 /**
  * Creates and returns a new `FIRQuery` that's additionally sorted by the specified field.