Ppl API Changes (#15344)

Co-authored-by: wu-hui <wu.hui.github@gmail.com>

Author: cherylEnkidu

Firestore/Swift/Source/ExprImpl.swift

@@ -19,37 +19,6 @@
 #endif // SWIFT_PACKAGE
 import Foundation
 
-@available(iOS 13, tvOS 13, macOS 10.15, macCatalyst 13, watchOS 7, *)
-struct RealtimePipelineSnapshot: Sendable {
-  /// The Pipeline on which `execute()` was called to obtain this `PipelineSnapshot`.
-  public let pipeline: RealtimePipeline
-
-  /// An array of all the results in the `PipelineSnapshot`.
-  let results_cache: [PipelineResult]
-
-  public let changes: [PipelineResultChange]
-  public let metadata: SnapshotMetadata
-
-  let bridge: __RealtimePipelineSnapshotBridge
-  private var options: PipelineListenOptions
-
-  init(_ bridge: __RealtimePipelineSnapshotBridge,
-       pipeline: RealtimePipeline,
-       options: PipelineListenOptions) {
-    self.bridge = bridge
-    self.pipeline = pipeline
-    self.options = options
-    metadata = bridge.metadata
-    results_cache = self.bridge.results
-      .map { PipelineResult($0, options.serverTimestamps ?? .none) }
-    changes = self.bridge.changes.map { PipelineResultChange($0) }
-  }
-
-  public func results() -> [PipelineResult] {
-    return results_cache
-  }
-}
-
 @available(iOS 13, tvOS 13, macOS 10.15, macCatalyst 13, watchOS 7, *)
 struct PipelineResultChange: Sendable {
   public enum ChangeType {

Firestore/Swift/Source/ExpressionImplementation.swift

@@ -23,15 +23,15 @@ import Foundation
 
 @objc public extension Firestore {
   @available(iOS 13, tvOS 13, macOS 10.15, macCatalyst 13, watchOS 7, *)
-  @nonobjc func pipeline() -> PipelineSource<Pipeline> {
-    return PipelineSource<Pipeline>(db: self) { stages, db in
+  @nonobjc func pipeline() -> PipelineSource {
+    return PipelineSource(db: self) { stages, db in
       Pipeline(stages: stages, db: db)
     }
   }
 
   @available(iOS 13, tvOS 13, macOS 10.15, macCatalyst 13, watchOS 7, *)
-  @nonobjc internal func realtimePipeline() -> PipelineSource<RealtimePipeline> {
-    return PipelineSource<RealtimePipeline>(db: self) { stages, db in
+  @nonobjc internal func realtimePipeline() -> RealtimePipelineSource {
+    return RealtimePipelineSource(db: self) { stages, db in
       RealtimePipeline(stages: stages, db: db)
     }
   }

Firestore/Swift/Source/SwiftAPI/Pipeline/RealtimePipelineSnapshot.swift renamed to Firestore/Swift/Source/PipelineResultChange.swift

@@ -18,6 +18,24 @@
   @_exported import FirebaseFirestoreInternal
 #endif // SWIFT_PACKAGE
 
+///
+/// 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.
+/// - Adding new fields with fixed values using `addFields`.
+/// - Providing literal arguments to functions like `sum` or `average`.
+///
+/// Example of using a `Constant` to add a new field:
+/// ```swift
+/// // Add a new field "source" with the value "manual" to each document
+/// firestore.pipeline()
+///   .collection("entries")
+///   .addFields([
+///     Constant("manual").as("source")
+///   ])
+/// ```
 public struct Constant: Expression, BridgeWrapper, @unchecked Sendable {
   let bridge: ExprBridge
 
@@ -33,55 +51,78 @@ public struct Constant: Expression, BridgeWrapper, @unchecked Sendable {
     }
   }
 
-  // Initializer for integer
+  /// Creates a new `Constant` expression from an integer literal.
+  ///
+  /// - Parameter value: The integer value.
   public init(_ value: Int) {
     self.init(value as Any)
   }
 
-  // Initializer for double
+  /// Creates a new `Constant` expression from a double-precision floating-point literal.
+  ///
+  /// - Parameter value: The double value.
   public init(_ value: Double) {
     self.init(value as Any)
   }
 
-  // Initializer for strings
+  /// Creates a new `Constant` expression from a string literal.
+  ///
+  /// - Parameter value: The string value.
   public init(_ value: String) {
     self.init(value as Any)
   }
 
-  // Initializer for boolean values
+  /// Creates a new `Constant` expression from a boolean literal.
+  ///
+  /// - Parameter value: The boolean value.
   public init(_ value: Bool) {
     self.init(value as Any)
   }
 
-  // Initializer for Bytes
+  /// Creates a new `Constant` expression from a `Data` (bytes) literal.
+  ///
+  /// - Parameter value: The `Data` value.
   public init(_ value: Data) {
     self.init(value as Any)
   }
 
-  // Initializer for GeoPoint values
+  /// Creates a new `Constant` expression from a `GeoPoint` literal.
+  ///
+  /// - Parameter value: The `GeoPoint` value.
   public init(_ value: GeoPoint) {
     self.init(value as Any)
   }
 
-  // Initializer for Timestamp values
+  /// Creates a new `Constant` expression from a `Timestamp` literal.
+  ///
+  /// - Parameter value: The `Timestamp` value.
   public init(_ value: Timestamp) {
     self.init(value as Any)
   }
 
-  // Initializer for Date values
+  /// Creates a new `Constant` expression from a `Date` literal.
+  ///
+  /// The `Date` will be converted to a `Timestamp` internally.
+  ///
+  /// - Parameter value: The `Date` value.
   public init(_ value: Date) {
     self.init(value as Any)
   }
 
-  // Initializer for DocumentReference
+  /// Creates a new `Constant` expression from a `DocumentReference` literal.
+  ///
+  /// - Parameter value: The `DocumentReference` value.
   public init(_ value: DocumentReference) {
     self.init(value as Any)
   }
 
-  // Initializer for vector values
+  /// Creates a new `Constant` expression from a `VectorValue` literal.
+  ///
+  /// - Parameter value: The `VectorValue` value.
   public init(_ value: VectorValue) {
     self.init(value as Any)
   }
 
+  /// A `Constant` representing a `nil`  value.
   public static let `nil` = Constant(nil)
 }