[AI] Remove deprecated totalBillableCharacters property (#15056)

Co-authored-by: google-labs-jules[bot] <161369871+google-labs-jules[bot]@users.noreply.github.com>

Author: ncooke3

FirebaseAI/CHANGELOG.md

@@ -1,3 +1,7 @@
+# Unreleased
+- [removed] Removed `CountTokensResponse.totalBillableCharacters` which was
+  deprecated in 11.15.0. Use `totalTokens` instead. (#15056)
+
 # 11.15.0
 - [fixed] Fixed `Sendable` warnings introduced in the Xcode 26 beta. (#14947)
 - [added] Added support for setting `title` in string, number and array `Schema`

FirebaseAI/Sources/Types/Internal/Requests/CountTokensRequest.swift

@@ -39,31 +39,11 @@ extension CountTokensRequest: GenerativeAIRequest {
 /// The model's response to a count tokens request.
 @available(iOS 15.0, macOS 12.0, macCatalyst 15.0, tvOS 15.0, watchOS 8.0, *)
 public struct CountTokensResponse: Sendable {
-  /// Container for deprecated properties or methods.
-  ///
-  /// This workaround allows deprecated fields to be referenced internally (for example in the
-  /// `init(from:)` constructor) without introducing compiler warnings.
-  struct Deprecated {
-    let totalBillableCharacters: Int?
-  }
-
   /// The total number of tokens in the input given to the model as a prompt.
   public let totalTokens: Int
 
-  /// The total number of billable characters in the text input given to the model as a prompt.
-  ///
-  /// > Important: This does not include billable image, video or other non-text input. See
-  /// [Vertex AI pricing](https://firebase.google.com/docs/vertex-ai/pricing) for details.
-  @available(*, deprecated, message: """
-  Use `totalTokens` instead; Gemini 2.0 series models and newer are always billed by token count.
-  """)
-  public var totalBillableCharacters: Int? { deprecated.totalBillableCharacters }
-
   /// The breakdown, by modality, of how many tokens are consumed by the prompt.
   public let promptTokensDetails: [ModalityTokenCount]
-
-  /// Deprecated properties or methods.
-  let deprecated: Deprecated
 }
 
 // MARK: - Codable Conformances
@@ -112,7 +92,6 @@ extension CountTokensRequest: Encodable {
 extension CountTokensResponse: Decodable {
   enum CodingKeys: CodingKey {
     case totalTokens
-    case totalBillableCharacters
     case promptTokensDetails
   }
 
@@ -121,8 +100,5 @@ extension CountTokensResponse: Decodable {
     totalTokens = try container.decodeIfPresent(Int.self, forKey: .totalTokens) ?? 0
     promptTokensDetails =
       try container.decodeIfPresent([ModalityTokenCount].self, forKey: .promptTokensDetails) ?? []
-    let totalBillableCharacters =
-      try container.decodeIfPresent(Int.self, forKey: .totalBillableCharacters)
-    deprecated = CountTokensResponse.Deprecated(totalBillableCharacters: totalBillableCharacters)
   }
 }

FirebaseAI/Tests/TestApp/Tests/Integration/CountTokensIntegrationTests.swift

@@ -57,12 +57,6 @@ struct CountTokensIntegrationTests {
     let response = try await model.countTokens(prompt)
 
     #expect(response.totalTokens == 6)
-    switch config.apiConfig.service {
-    case .vertexAI:
-      #expect(response.deprecated.totalBillableCharacters == 16)
-    case .googleAI:
-      #expect(response.deprecated.totalBillableCharacters == nil)
-    }
     #expect(response.promptTokensDetails.count == 1)
     let promptTokensDetails = try #require(response.promptTokensDetails.first)
     #expect(promptTokensDetails.modality == .text)
@@ -81,12 +75,6 @@ struct CountTokensIntegrationTests {
     let response = try await model.countTokens("What is your favourite colour?")
 
     #expect(response.totalTokens == 14)
-    switch config.apiConfig.service {
-    case .vertexAI:
-      #expect(response.deprecated.totalBillableCharacters == 61)
-    case .googleAI:
-      #expect(response.deprecated.totalBillableCharacters == nil)
-    }
     #expect(response.promptTokensDetails.count == 1)
     let promptTokensDetails = try #require(response.promptTokensDetails.first)
     #expect(promptTokensDetails.modality == .text)
@@ -115,12 +103,10 @@ struct CountTokensIntegrationTests {
     switch config.apiConfig.service {
     case .vertexAI:
       #expect(response.totalTokens == 65)
-      #expect(response.deprecated.totalBillableCharacters == 170)
     case .googleAI:
       // The Developer API erroneously ignores the `responseSchema` when counting tokens, resulting
       // in a lower total count than Vertex AI.
       #expect(response.totalTokens == 34)
-      #expect(response.deprecated.totalBillableCharacters == nil)
     }
     #expect(response.promptTokensDetails.count == 1)
     let promptTokensDetails = try #require(response.promptTokensDetails.first)

FirebaseAI/Tests/TestApp/Tests/Integration/IntegrationTests.swift

@@ -85,7 +85,6 @@ final class IntegrationTests: XCTestCase {
     let response = try await model.countTokens(prompt)
 
     XCTAssertEqual(response.totalTokens, 14)
-    XCTAssertEqual(response.deprecated.totalBillableCharacters, 51)
     XCTAssertEqual(response.promptTokensDetails.count, 1)
     let promptTokensDetails = try XCTUnwrap(response.promptTokensDetails.first)
     XCTAssertEqual(promptTokensDetails.modality, .text)
@@ -102,7 +101,6 @@ final class IntegrationTests: XCTestCase {
       let response = try await model.countTokens(image)
 
       XCTAssertEqual(response.totalTokens, 266)
-      XCTAssertEqual(response.deprecated.totalBillableCharacters, 35)
       XCTAssertEqual(response.promptTokensDetails.count, 2) // Image prompt + system instruction
       let textPromptTokensDetails = try XCTUnwrap(response.promptTokensDetails.first {
         $0.modality == .text
@@ -122,7 +120,6 @@ final class IntegrationTests: XCTestCase {
     let response = try await model.countTokens(fileData)
 
     XCTAssertEqual(response.totalTokens, 266)
-    XCTAssertEqual(response.deprecated.totalBillableCharacters, 35)
     XCTAssertEqual(response.promptTokensDetails.count, 2) // Image prompt + system instruction
     let textPromptTokensDetails = try XCTUnwrap(response.promptTokensDetails.first {
       $0.modality == .text
@@ -141,7 +138,6 @@ final class IntegrationTests: XCTestCase {
     let response = try await model.countTokens(fileData)
 
     XCTAssertEqual(response.totalTokens, 266)
-    XCTAssertEqual(response.deprecated.totalBillableCharacters, 35)
   }
 
   func testCountTokens_image_fileData_requiresUserAuth_userSignedIn() async throws {
@@ -152,7 +148,6 @@ final class IntegrationTests: XCTestCase {
     let response = try await model.countTokens(fileData)
 
     XCTAssertEqual(response.totalTokens, 266)
-    XCTAssertEqual(response.deprecated.totalBillableCharacters, 35)
   }
 
   func testCountTokens_image_fileData_requiresUserAuth_wrongUser_permissionDenied() async throws {
@@ -193,7 +188,6 @@ final class IntegrationTests: XCTestCase {
     ])
 
     XCTAssertGreaterThan(response.totalTokens, 0)
-    XCTAssertEqual(response.deprecated.totalBillableCharacters, 71)
     XCTAssertEqual(response.promptTokensDetails.count, 1)
     let promptTokensDetails = try XCTUnwrap(response.promptTokensDetails.first)
     XCTAssertEqual(promptTokensDetails.modality, .text)

FirebaseAI/Tests/Unit/GenerativeModelVertexAITests.swift

@@ -1517,7 +1517,6 @@ final class GenerativeModelVertexAITests: XCTestCase {
     let response = try await model.countTokens("Why is the sky blue?")
 
     XCTAssertEqual(response.totalTokens, 6)
-    XCTAssertEqual(response.deprecated.totalBillableCharacters, 16)
   }
 
   func testCountTokens_succeeds_detailed() async throws {
@@ -1530,7 +1529,6 @@ final class GenerativeModelVertexAITests: XCTestCase {
     let response = try await model.countTokens("Why is the sky blue?")
 
     XCTAssertEqual(response.totalTokens, 1837)
-    XCTAssertEqual(response.deprecated.totalBillableCharacters, 117)
     XCTAssertEqual(response.promptTokensDetails.count, 2)
     XCTAssertEqual(response.promptTokensDetails[0].modality, .image)
     XCTAssertEqual(response.promptTokensDetails[0].tokenCount, 1806)
@@ -1577,7 +1575,6 @@ final class GenerativeModelVertexAITests: XCTestCase {
     let response = try await model.countTokens("Why is the sky blue?")
 
     XCTAssertEqual(response.totalTokens, 6)
-    XCTAssertEqual(response.deprecated.totalBillableCharacters, 16)
   }
 
   func testCountTokens_succeeds_noBillableCharacters() async throws {
@@ -1590,7 +1587,6 @@ final class GenerativeModelVertexAITests: XCTestCase {
     let response = try await model.countTokens(InlineDataPart(data: Data(), mimeType: "image/jpeg"))
 
     XCTAssertEqual(response.totalTokens, 258)
-    XCTAssertNil(response.deprecated.totalBillableCharacters)
   }
 
   func testCountTokens_modelNotFound() async throws {