chore: Implement std::error::Error::source for InlineError

Author: Stranger6667

CHANGELOG.md

@@ -5,6 +5,7 @@
 ### Changed
 
 - Display stylesheet location in network-related errors.
+- Implement `std::error::Error::source` for `InlineError`.
 
 ### Performance
 

bindings/javascript/__test__/wasm.spec.ts

@@ -84,5 +84,8 @@ test("unsupported network operation", (t) => {
     },
     { any: true },
   );
-  t.is(error, "Loading remote stylesheets is not supported on WASM");
+  t.is(
+    error,
+    "Loading remote stylesheets is not supported on WASM: http://127.0.0.1:5000/external.css",
+  );
 });

bindings/javascript/src/errors.rs

@@ -44,12 +44,15 @@ impl From<InlineError> for JsValue {
             css_inline::InlineError::ParseError(e) => JsValue::from_str(e),
             css_inline::InlineError::Network {
                 error: network_error,
-                ..
+                location,
             } => {
                 if let attohttpc::ErrorKind::Io(io_error) = network_error.kind() {
                     if io_error.kind() == std::io::ErrorKind::Unsupported {
                         return JsValue::from_str(
-                            "Loading remote stylesheets is not supported on WASM",
+                            format!(
+                                "Loading remote stylesheets is not supported on WASM: {location}"
+                            )
+                            .as_str(),
                         );
                     }
                 }

bindings/javascript/wasm/index_bg.wasm

@@ -36,7 +36,16 @@ impl From<io::Error> for InlineError {
     }
 }
 
-impl Error for InlineError {}
+impl Error for InlineError {
+    fn source(&self) -> Option<&(dyn Error + 'static)> {
+        match self {
+            InlineError::IO(error) => Some(error),
+            #[cfg(feature = "http")]
+            InlineError::Network { error, .. } => Some(error),
+            InlineError::MissingStyleSheet { .. } | InlineError::ParseError(_) => None,
+        }
+    }
+}
 
 impl Display for InlineError {
     fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {