fix(wasm-sdk): include groups and tokens in data contract serialization

packages/wasm-sdk/src/dpp.rs

@@ -297,9 +297,18 @@ impl IdentityWasm {
 #[wasm_bindgen]
 pub struct DataContractWasm(DataContract);
 
-impl From<DataContract> for DataContractWasm {
-    fn from(value: DataContract) -> Self {
-        Self(value)
+impl DataContractWasm {
+    /// Create a DataContractWasm from a DataContract.
+    ///
+    /// This is the primary constructor for wrapping a data contract.
+    /// Note that serialization via `to_json()` requires providing an explicit
+    /// platform version to ensure version-specific fields (e.g., `groups` and
+    /// `tokens` for token contracts) are correctly included.
+    ///
+    /// # Arguments
+    /// * `data_contract` - The data contract to wrap
+    pub(crate) fn from_data_contract(data_contract: DataContract) -> Self {
+        Self(data_contract)
     }
 }
 
@@ -310,8 +319,12 @@ impl DataContractWasm {
     }
 
     #[wasm_bindgen(js_name=toJSON)]
-    pub fn to_json(&self) -> Result<JsValue, WasmSdkError> {
-        let platform_version = PlatformVersion::first();
+    pub fn to_json(&self, platform_version: u32) -> Result<JsValue, WasmSdkError> {
+        let platform_version = &PlatformVersion::get(platform_version).map_err(|e| {
+            WasmSdkError::invalid_argument(format!(
+                "unknown platform version {platform_version}: {e}"
+            ))
+        })?;
 
         let json = self.0.to_json(platform_version).map_err(|e| {
             WasmSdkError::serialization(format!(

packages/wasm-sdk/src/queries/data_contract.rs

@@ -36,10 +36,11 @@ impl WasmSdk {
         )
         .map_err(|e| WasmSdkError::invalid_argument(format!("Invalid data contract ID: {}", e)))?;
 
-        DataContract::fetch_by_identifier(self.as_ref(), id)
+        let contract = DataContract::fetch_by_identifier(self.as_ref(), id)
             .await?
-            .ok_or_else(|| WasmSdkError::not_found("Data contract not found"))
-            .map(Into::into)
+            .ok_or_else(|| WasmSdkError::not_found("Data contract not found"))?;
+
+        Ok(DataContractWasm::from_data_contract(contract))
     }
 
     #[wasm_bindgen(js_name = "getDataContractWithProofInfo")]

packages/wasm-sdk/src/verify.rs

@@ -122,7 +122,7 @@ pub async fn verify_data_contract() -> Option<DataContractWasm> {
     )
     .expect("parse proof");
 
-    response.map(DataContractWasm::from)
+    response.map(DataContractWasm::from_data_contract)
 }
 
 #[wasm_bindgen(js_name = "verifyDocuments")]