add abs()

Author: cherylEnkidu

Firestore/Swift/Source/ExpressionImplementation.swift

@@ -25,6 +25,10 @@ public extension Expression {
 
   // MARK: Arithmetic Operators
 
+  func abs() -> FunctionExpression {
+    return FunctionExpression("abs", [self])
+  }
+
   func add(_ value: Expression) -> FunctionExpression {
     return FunctionExpression("add", [self, value])
   }

Firestore/Swift/Source/SwiftAPI/Pipeline/Expressions/Constant.swift

@@ -19,7 +19,8 @@
 #endif // SWIFT_PACKAGE
 
 ///
-/// A `Constant` is an `Expression` that represents a fixed, literal value within a Firestore pipeline.
+/// A `Constant` is an `Expression` that represents a fixed, literal value within a Firestore
+/// pipeline.
 ///
 /// `Constant`s are used to introduce literal values into a query, which can be useful for:
 /// - Comparing a field to a specific value in a `where` clause.

Firestore/Swift/Source/SwiftAPI/Pipeline/Expressions/Expression.swift

@@ -36,6 +36,16 @@ public protocol Expression: Sendable {
 
   // --- Added Mathematical Operations ---
 
+  /// Creates an expression that returns the absolute value of the number.
+  ///
+  /// ```swift
+  /// // Get the absolute value of the "amount" field.
+  /// Field("amount").abs()
+  /// ```
+  ///
+  /// - Returns: A new `FunctionExpression` representing the absolute value of the number.
+  func abs() -> FunctionExpression
+
   /// Creates an expression that adds another expression to this expression.
   /// To add multiple expressions, chain calls to this method.
   /// Assumes `self` and the parameter evaluate to compatible types for addition (e.g., numbers, or

Firestore/Swift/Source/SwiftAPI/Pipeline/Expressions/FunctionExpressions/ArrayExpression.swift

@@ -40,4 +40,4 @@ public class ArrayExpression: FunctionExpression, @unchecked Sendable {
 
     super.init("array", result)
   }
-}
+}

Firestore/Swift/Source/SwiftAPI/Pipeline/Expressions/FunctionExpressions/MapExpression.swift

@@ -38,4 +38,4 @@ public class MapExpression: FunctionExpression, @unchecked Sendable {
 
     super.init("map", result)
   }
-}
+}

Firestore/Swift/Source/SwiftAPI/Pipeline/Ordering.swift

@@ -20,7 +20,7 @@ public struct Ordering: @unchecked Sendable {
   let bridge: OrderingBridge
 
   init(expression: Expression, direction: Direction) {
-    self.expr = expression
+    expr = expression
     self.direction = direction
     bridge = OrderingBridge(expr: expression.toBridge(), direction: direction.rawValue)
   }

Firestore/Swift/Source/SwiftAPI/Pipeline/RealtimePipelineSource.swift

@@ -13,7 +13,7 @@
 // limitations under the License.
 
 @available(iOS 13, tvOS 13, macOS 10.15, macCatalyst 13, watchOS 7, *)
-internal struct RealtimePipelineSource: @unchecked Sendable {
+struct RealtimePipelineSource: @unchecked Sendable {
   let db: Firestore
   let factory: ([Stage], Firestore) -> RealtimePipeline
 
@@ -22,26 +22,26 @@ internal struct RealtimePipelineSource: @unchecked Sendable {
     self.factory = factory
   }
 
-  internal func collection(_ path: String) -> RealtimePipeline {
+  func collection(_ path: String) -> RealtimePipeline {
     return factory([CollectionSource(collection: db.collection(path), db: db)], db)
   }
 
-  internal func collection(_ coll: CollectionReference) -> RealtimePipeline {
+  func collection(_ coll: CollectionReference) -> RealtimePipeline {
     return factory([CollectionSource(collection: coll, db: db)], db)
   }
 
-  internal func collectionGroup(_ collectionId: String) -> RealtimePipeline {
+  func collectionGroup(_ collectionId: String) -> RealtimePipeline {
     return factory(
       [CollectionGroupSource(collectionId: collectionId)],
       db
     )
   }
 
-  internal func documents(_ docs: [DocumentReference]) -> RealtimePipeline {
+  func documents(_ docs: [DocumentReference]) -> RealtimePipeline {
     return factory([DocumentsSource(docs: docs, db: db)], db)
   }
 
-  internal func documents(_ paths: [String]) -> RealtimePipeline {
+  func documents(_ paths: [String]) -> RealtimePipeline {
     let docs = paths.map { db.document($0) }
     return factory([DocumentsSource(docs: docs, db: db)], db)
   }

Firestore/Swift/Tests/Integration/PipelineTests.swift

@@ -823,8 +823,8 @@ class PipelineIntegrationTests: FSTIntegrationTestCase {
       XCTFail("No result for min/max/count/countAll aggregation")
     }
   }
-  
-// Hide this test due to `.countIf()` design is incomplete.
+
+  // Hide this test due to `.countIf()` design is incomplete.
 //  func testReturnsCountIfAccumulation() async throws {
 //    let collRef = collectionRef(withDocuments: bookDocs)
 //    let db = collRef.firestore
@@ -1949,6 +1949,32 @@ class PipelineIntegrationTests: FSTIntegrationTestCase {
     }
   }
 
+  func testAbsWorks() async throws {
+    let collRef = collectionRef(withDocuments: [
+      "doc1": ["value": -10],
+      "doc2": ["value": 5],
+      "doc3": ["value": 0],
+    ])
+    let db = collRef.firestore
+
+    let pipeline = db.pipeline()
+      .collection(collRef.path)
+      .select([
+        Field("value").abs().as("absValue"),
+      ])
+      .sort([Field("absValue").ascending()])
+
+    let snapshot = try await pipeline.execute()
+
+    let expectedResults: [[String: Sendable]] = [
+      ["absValue": 0],
+      ["absValue": 5],
+      ["absValue": 10],
+    ]
+
+    TestHelper.compare(pipelineSnapshot: snapshot, expected: expectedResults, enforceOrder: true)
+  }
+
   func testComparisonOperators() async throws {
     let collRef = collectionRef(withDocuments: bookDocs)
     let db = collRef.firestore