Fixed RuntimeError start when instantiating wasmer-js

lib/js-api/src/instance.rs

@@ -1,9 +1,11 @@
+use crate::env::HostEnvInitError;
 use crate::export::Export;
 use crate::exports::Exports;
 use crate::externals::Extern;
 use crate::module::Module;
-use crate::store::Store;
 use crate::resolver::Resolver;
+use crate::store::Store;
+use crate::trap::RuntimeError;
 use js_sys::WebAssembly;
 use std::fmt;
 use thiserror::Error;
@@ -39,10 +41,13 @@ pub enum InstantiationError {
     Link(String),
 
     /// A runtime error occured while invoking the start function
-    #[cfg_attr(feature = "std", error("Start error: {0}"))]
-    Start(String),
-}
+    #[error(transparent)]
+    Start(RuntimeError),
 
+    /// Error occurred when initializing the host environment.
+    #[error(transparent)]
+    HostEnvInitialization(HostEnvInitError),
+}
 
 impl Instance {
     /// Creates a new `Instance` from a WebAssembly [`Module`] and a
@@ -80,7 +85,9 @@ impl Instance {
     ///  * Runtime errors that happen when running the module `start` function.
     pub fn new(module: &Module, resolver: &dyn Resolver) -> Result<Self, InstantiationError> {
         let store = module.store();
-        let (instance, functions) = module.instantiate(resolver).unwrap();
+        let (instance, functions) = module
+            .instantiate(resolver)
+            .map_err(|e| InstantiationError::Start(e))?;
         let instance_exports = instance.exports();
         let exports = module
             .exports()
@@ -100,7 +107,8 @@ impl Instance {
             exports,
         };
         for func in functions {
-            func.init_envs(&self_instance).unwrap();
+            func.init_envs(&self_instance)
+                .map_err(|e| InstantiationError::HostEnvInitialization(e))?;
         }
         Ok(self_instance)
     }

lib/js-api/src/module.rs

@@ -12,6 +12,7 @@ use std::fmt;
 use std::io;
 use std::path::Path;
 use thiserror::Error;
+use wasm_bindgen::JsValue;
 use wasmer_types::{
     ExportsIterator, ExternType, FunctionType, GlobalType, ImportsIterator, MemoryType, Mutability,
     Pages, TableType, Type,
@@ -244,7 +245,8 @@ impl Module {
             // the error for us, so we don't need to handle it
         }
         Ok((
-            WebAssembly::Instance::new(&self.module, &imports).unwrap(),
+            WebAssembly::Instance::new(&self.module, &imports)
+                .map_err(|e: JsValue| -> RuntimeError { e.into() })?,
             functions,
         ))
     }

lib/js-api/src/types.rs

@@ -28,7 +28,10 @@ pub fn param_from_js(ty: &ValType, js_val: &JsValue) -> Val {
         ValType::I64 => Val::I64(js_val.as_f64().unwrap() as _),
         ValType::F32 => Val::F32(js_val.as_f64().unwrap() as _),
         ValType::F64 => Val::F64(js_val.as_f64().unwrap()),
-        t => unimplemented!("The type `{:?}` is not yet supported in the JS Function API", t),
+        t => unimplemented!(
+            "The type `{:?}` is not yet supported in the JS Function API",
+            t
+        ),
     }
 }
 
@@ -40,7 +43,10 @@ impl AsJs for Val {
             Self::F32(f) => JsValue::from_f64(*f as f64),
             Self::F64(f) => JsValue::from_f64(*f),
             Self::FuncRef(func) => func.as_ref().unwrap().exported.function.clone().into(),
-            v => unimplemented!("The value `{:?}` is not yet supported in the JS Function API", v),
+            v => unimplemented!(
+                "The value `{:?}` is not yet supported in the JS Function API",
+                v
+            ),
         }
     }
 }