refactor: suppress use of to_string_lossy

Author: Kogia-sima

sailfish-compiler/src/procmacro.rs

@@ -225,13 +225,18 @@ fn derive_template_impl(tokens: TokenStream) -> Result<TokenStream, syn::Error>
     let report = compile(&*input_file, &*output_file, config)
         .map_err(|e| syn::Error::new(Span::call_site(), e))?;
 
-    let input_file_string = input_file.to_string_lossy();
-    let output_file_string = output_file.to_string_lossy();
+    let input_file_string = input_file
+        .to_str()
+        .unwrap_or_else(|| panic!("Non UTF-8 file name: {:?}", input_file));
+    let output_file_string = output_file
+        .to_str()
+        .unwrap_or_else(|| panic!("Non UTF-8 file name: {:?}", output_file));
 
     let mut include_bytes_seq = quote! { include_bytes!(#input_file_string); };
     for dep in report.deps {
-        let dep_string = dep.to_string_lossy();
-        include_bytes_seq.extend(quote! { include_bytes!(#dep_string); });
+        if let Some(dep_string) = dep.to_str() {
+            include_bytes_seq.extend(quote! { include_bytes!(#dep_string); });
+        }
     }
 
     // Generate tokens

sailfish-compiler/src/resolver.rs

@@ -54,8 +54,16 @@ impl<'h> ResolverImpl<'h> {
             } else {
                 self.path_stack.last().unwrap().parent().unwrap().join(arg)
             };
-            let absolute_path_str = absolute_path.to_string_lossy();
-            return Ok(syn::parse2(quote! { include!(#absolute_path_str) }).unwrap());
+
+            return if let Some(absolute_path_str) = absolute_path.to_str() {
+                Ok(syn::parse2(quote! { include!(#absolute_path_str) }).unwrap())
+            } else {
+                let msg = format!(
+                    "cannot include path with non UTF-8 character: {:?}",
+                    absolute_path
+                );
+                Err(make_error!(ErrorKind::AnalyzeError(msg)))
+            };
         }
 
         // resolve the template file path