chore: Add [[nodiscard]] attribute to native functions (#660)

## Description

As in the title, add `[[nodiscard]]` attribute to exported functions in
native implementation.

### Introduces a breaking change?

- [ ] Yes
- [x] No

### Type of change

- [ ] Bug fix (change which fixes an issue)
- [ ] New feature (change which adds functionality)
- [ ] Documentation update (improves or adds clarity to existing
documentation)
- [x] Other (chores, tests, code style improvements etc.)

### Tested on

- [x] iOS
- [ ] Android

### Testing instructions

Check if all demo apps work the same as previously

### Screenshots

<!-- Add screenshots here, if applicable -->

### Related issues

Closes #448 

### Checklist

- [x] I have performed a self-review of my code
- [ ] I have commented my code, particularly in hard-to-understand areas
- [ ] I have updated the documentation accordingly
- [x] My changes generate no new warnings

### Additional notes

<!-- Include any additional information, assumptions, or context that
reviewers might need to understand this PR. -->

---------

Co-authored-by: Mateusz Słuszniak <mateusz.sluszniak@swmansion.com>
Co-authored-by: Mateusz Sluszniak <56299341+msluszniak@users.noreply.github.com>
Co-authored-by: Bartek <116185412+benITo47@users.noreply.github.com>

Author: 3 people

packages/react-native-executorch/common/rnexecutorch/TokenizerModule.h

@@ -11,11 +11,16 @@ class TokenizerModule {
 public:
   explicit TokenizerModule(std::string source,
                            std::shared_ptr<react::CallInvoker> callInvoker);
-  std::vector<int32_t> encode(std::string s) const;
-  std::string decode(std::vector<int32_t> vec, bool skipSpecialTokens) const;
-  std::string idToToken(int32_t tokenId) const;
-  int32_t tokenToId(std::string token) const;
-  std::size_t getVocabSize() const;
+  [[nodiscard("Registered non-void function")]] std::vector<int32_t>
+  encode(std::string s) const;
+  [[nodiscard("Registered non-void function")]] std::string
+  decode(std::vector<int32_t> vec, bool skipSpecialTokens) const;
+  [[nodiscard("Registered non-void function")]] std::string
+  idToToken(int32_t tokenId) const;
+  [[nodiscard("Registered non-void function")]] int32_t
+  tokenToId(std::string token) const;
+  [[nodiscard("Registered non-void function")]] std::size_t
+  getVocabSize() const;
   std::size_t getMemoryLowerBound() const noexcept;
 
 private:

packages/react-native-executorch/common/rnexecutorch/host_objects/ModelHostObject.h

@@ -34,15 +34,11 @@ template <typename Model> class ModelHostObject : public JsiHostObject {
     if constexpr (meta::DerivedFromOrSameAs<Model, models::BaseModel>) {
       addFunctions(
           JSI_EXPORT_FUNCTION(ModelHostObject<Model>, unload, "unload"));
-    }
 
-    if constexpr (meta::DerivedFromOrSameAs<Model, models::BaseModel>) {
       addFunctions(JSI_EXPORT_FUNCTION(ModelHostObject<Model>,
                                        promiseHostFunction<&Model::forwardJS>,
                                        "forward"));
-    }
 
-    if constexpr (meta::DerivedFromOrSameAs<Model, models::BaseModel>) {
       addFunctions(JSI_EXPORT_FUNCTION(
           ModelHostObject<Model>, promiseHostFunction<&Model::getInputShape>,
           "getInputShape"));
@@ -89,13 +85,6 @@ template <typename Model> class ModelHostObject : public JsiHostObject {
     }
 
     if constexpr (meta::SameAs<Model, TokenizerModule>) {
-      addFunctions(JSI_EXPORT_FUNCTION(ModelHostObject<Model>,
-                                       promiseHostFunction<&Model::encode>,
-                                       "encode"));
-
-      addFunctions(JSI_EXPORT_FUNCTION(ModelHostObject<Model>,
-                                       promiseHostFunction<&Model::decode>,
-                                       "decode"));
       addFunctions(JSI_EXPORT_FUNCTION(
           ModelHostObject<Model>, promiseHostFunction<&Model::getVocabSize>,
           "getVocabSize"));
@@ -108,10 +97,6 @@ template <typename Model> class ModelHostObject : public JsiHostObject {
     }
 
     if constexpr (meta::SameAs<Model, models::llm::LLM>) {
-      addFunctions(JSI_EXPORT_FUNCTION(ModelHostObject<Model>,
-                                       promiseHostFunction<&Model::generate>,
-                                       "generate"));
-
       addFunctions(JSI_EXPORT_FUNCTION(
           ModelHostObject<Model>, synchronousHostFunction<&Model::interrupt>,
           "interrupt"));

packages/react-native-executorch/common/rnexecutorch/models/BaseModel.h

@@ -25,11 +25,11 @@ class BaseModel {
       Module::LoadMode loadMode = Module::LoadMode::MmapUseMlockIgnoreErrors);
   std::size_t getMemoryLowerBound() const noexcept;
   void unload() noexcept;
-  std::vector<int32_t> getInputShape(std::string method_name,
-                                     int32_t index) const;
+  [[nodiscard("Registered non-void function")]] std::vector<int32_t>
+  getInputShape(std::string method_name, int32_t index) const;
   std::vector<std::vector<int32_t>>
   getAllInputShapes(std::string methodName = "forward") const;
-  std::vector<JSTensorViewOut>
+  [[nodiscard("Registered non-void function")]] std::vector<JSTensorViewOut>
   forwardJS(std::vector<JSTensorViewIn> tensorViewVec) const;
   Result<std::vector<EValue>> forward(const EValue &input_value) const;
   Result<std::vector<EValue>>

packages/react-native-executorch/common/rnexecutorch/models/classification/Classification.h

@@ -17,7 +17,9 @@ class Classification : public BaseModel {
 public:
   Classification(const std::string &modelSource,
                  std::shared_ptr<react::CallInvoker> callInvoker);
-  std::unordered_map<std::string_view, float> generate(std::string imageSource);
+  [[nodiscard("Registered non-void function")]] std::unordered_map<
+      std::string_view, float>
+  generate(std::string imageSource);
 
 private:
   std::unordered_map<std::string_view, float> postprocess(const Tensor &tensor);

packages/react-native-executorch/common/rnexecutorch/models/embeddings/image/ImageEmbeddings.h

@@ -16,7 +16,9 @@ class ImageEmbeddings final : public BaseEmbeddings {
 public:
   ImageEmbeddings(const std::string &modelSource,
                   std::shared_ptr<react::CallInvoker> callInvoker);
-  std::shared_ptr<OwningArrayBuffer> generate(std::string imageSource);
+  [[nodiscard(
+      "Registered non-void function")]] std::shared_ptr<OwningArrayBuffer>
+  generate(std::string imageSource);
 
 private:
   cv::Size modelImageSize{0, 0};

packages/react-native-executorch/common/rnexecutorch/models/embeddings/text/TextEmbeddings.h

@@ -17,7 +17,9 @@ class TextEmbeddings final : public BaseEmbeddings {
   TextEmbeddings(const std::string &modelSource,
                  const std::string &tokenizerSource,
                  std::shared_ptr<react::CallInvoker> callInvoker);
-  std::shared_ptr<OwningArrayBuffer> generate(const std::string input);
+  [[nodiscard(
+      "Registered non-void function")]] std::shared_ptr<OwningArrayBuffer>
+  generate(const std::string input);
 
 private:
   std::vector<std::vector<int32_t>> inputShapes;

packages/react-native-executorch/common/rnexecutorch/models/image_segmentation/ImageSegmentation.h

@@ -23,7 +23,7 @@ class ImageSegmentation : public BaseModel {
 public:
   ImageSegmentation(const std::string &modelSource,
                     std::shared_ptr<react::CallInvoker> callInvoker);
-  std::shared_ptr<jsi::Object>
+  [[nodiscard("Registered non-void function")]] std::shared_ptr<jsi::Object>
   generate(std::string imageSource,
            std::set<std::string, std::less<>> classesOfInterest, bool resize);
 

packages/react-native-executorch/common/rnexecutorch/models/object_detection/ObjectDetection.h

@@ -20,8 +20,8 @@ class ObjectDetection : public BaseModel {
 public:
   ObjectDetection(const std::string &modelSource,
                   std::shared_ptr<react::CallInvoker> callInvoker);
-  std::vector<types::Detection> generate(std::string imageSource,
-                                         double detectionThreshold);
+  [[nodiscard("Registered non-void function")]] std::vector<types::Detection>
+  generate(std::string imageSource, double detectionThreshold);
 
 private:
   std::vector<types::Detection> postprocess(const std::vector<EValue> &tensors,

packages/react-native-executorch/common/rnexecutorch/models/ocr/Detector.h

@@ -21,8 +21,9 @@ class Detector : public BaseModel {
 public:
   explicit Detector(const std::string &modelSource,
                     std::shared_ptr<react::CallInvoker> callInvoker);
-  virtual std::vector<types::DetectorBBox> generate(const cv::Mat &inputImage,
-                                                    int32_t inputWidth);
+  [[nodiscard("Registered non-void function")]] 
+  virtual std::vector<types::DetectorBBox> 
+  generate(const cv::Mat &inputImage, int32_t inputWidth);
 
   cv::Size calculateModelImageSize(int32_t methodInputWidth);
 

packages/react-native-executorch/common/rnexecutorch/models/ocr/OCR.h

@@ -27,7 +27,8 @@ class OCR final {
   explicit OCR(const std::string &detectorSource,
                const std::string &recognizerSource, const std::string &symbols,
                std::shared_ptr<react::CallInvoker> callInvoker);
-  std::vector<types::OCRDetection> generate(std::string input);
+  [[nodiscard("Registered non-void function")]] std::vector<types::OCRDetection>
+  generate(std::string input);
   std::size_t getMemoryLowerBound() const noexcept;
   void unload() noexcept;