Add Voxtral test. (pytorch#14918)

Summary:
X-link: meta-pytorch/tokenizers#136

.

Differential Revision: D84081392

Author: shoumikhin

extension/llm/apple/ExecuTorchLLM/Exported/ExecuTorchLLMMultimodalRunner.h

@@ -145,7 +145,7 @@ __attribute__((objc_subclassing_restricted))
  @return A retained ExecuTorchLLMMultimodalInput instance of type Audio.
 */
 + (instancetype)inputWithAudio:(ExecuTorchLLMAudio *)audio
-    NS_SWIFT_NAME(init(audio:))
+    NS_SWIFT_NAME(init(_:))
     NS_RETURNS_RETAINED;
 
 @property(nonatomic, readonly) ExecuTorchLLMMultimodalInputType type;

extension/llm/apple/ExecuTorchLLM/__tests__/MultimodalRunnerTest.swift

@@ -6,6 +6,7 @@
  * LICENSE file in the root directory of this source tree.
  */
 
+import ExecuTorch
 import ExecuTorchLLM
 import XCTest
 
@@ -98,10 +99,10 @@ extension UIImage {
 
 class MultimodalRunnerTest: XCTestCase {
   let systemPrompt = "A chat between a curious human and an artificial intelligence assistant. The assistant gives helpful, detailed, and polite answers to the human's questions."
-  let userPrompt = "What's on the picture?"
 
   func testGemma() {
     let chatTemplate = "<start_of_turn>user\n%@<end_of_turn>\n<start_of_turn>model"
+    let userPrompt = "What's on the picture?"
     let sideSize: CGFloat = 896
     let sequenceLength = 768
     let bundle = Bundle(for: type(of: self))
@@ -156,6 +157,7 @@ class MultimodalRunnerTest: XCTestCase {
 
   func testLLaVA() {
     let chatTemplate = "USER: %@ ASSISTANT: "
+    let userPrompt = "What's on the picture?"
     let sideSize: CGFloat = 336
     let sequenceLength = 768
     let bundle = Bundle(for: type(of: self))
@@ -201,4 +203,47 @@ class MultimodalRunnerTest: XCTestCase {
     }
     XCTAssertTrue(text.lowercased().contains("waterfall"))
   }
+
+  func testVoxtral() throws {
+    let chatTemplate = "%@[/INST]"
+    let userPrompt = "What is the audio about?"
+    let bundle = Bundle(for: type(of: self))
+    guard let modelPath = bundle.path(forResource: "voxtral", ofType: "pte"),
+          let tokenizerPath = bundle.path(forResource: "voxtral_tokenizer_tekken", ofType: "json"),
+          let audioPath = bundle.path(forResource: "voxtral_input_features", ofType: "bin") else {
+      XCTFail("Couldn't find model or tokenizer files")
+      return
+    }
+    let runner = MultimodalRunner(modelPath: modelPath, tokenizerPath: tokenizerPath)
+    var audioData = try Data(contentsOf: URL(fileURLWithPath: audioPath), options: .mappedIfSafe)
+    let floatSize = MemoryLayout<Float>.size
+    guard audioData.count % floatSize == 0 else {
+      XCTFail("Invalid audio data")
+      return
+    }
+    let bins = 128
+    let frames = 3000
+    let batchSize = audioData.count / floatSize / (bins * frames)
+    var text = ""
+
+    do {
+      try runner.generate([
+        MultimodalInput("<s>[INST][BEGIN_AUDIO]"),
+        MultimodalInput(Audio(
+          float: audioData,
+          batchSize: batchSize,
+          bins: bins,
+          frames: frames
+        )),
+        MultimodalInput(String(format: chatTemplate, userPrompt)),
+      ], Config {
+        $0.maximumNewTokens = 256
+      }) { token in
+        text += token
+      }
+    } catch {
+      XCTFail("Failed to generate text with error \(error)")
+    }
+    XCTAssertTrue(text.lowercased().contains("tattoo"))
+  }
 }