Merge #2829

2829: Improve error message oriented from JS object r=syrusakbary a=kateinoigakukun


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# Description
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`JsValue.as_string` converts the value to String iff the value is a
String itself, so the error message always failovers to empty string.
`JsValue` impls `Debug` using `JSON.stringify`, and it gives better
description of the error.


# Review

- [ ] Add a short description of the change to the CHANGELOG.md file


Co-authored-by: Yuta Saito <[email protected]>
Co-authored-by: Syrus Akbary <[email protected]>

CHANGELOG.md

@@ -9,6 +9,7 @@ Looking for changes that affect our C API? See the [C API Changelog](lib/c-api/C
 ## **Unreleased**
 
 ### Fixed
+- [#2829](https://github.com/wasmerio/wasmer/pull/2829) Improve error message oriented from JS object.
 - [#2828](https://github.com/wasmerio/wasmer/pull/2828) Fix JsImportObject resolver.
 
 ## 2.2.1 - 2022/03/15

lib/api/src/js/trap.rs

@@ -43,7 +43,7 @@ impl fmt::Display for RuntimeErrorSource {
         match self {
             Self::Generic(s) => write!(f, "{}", s),
             Self::User(s) => write!(f, "{}", s),
-            Self::Js(s) => write!(f, "{}", s.as_string().unwrap_or("".to_string())),
+            Self::Js(s) => write!(f, "{:?}", s),
         }
     }
 }