Merge branch 'improve-errormsg' into 'main'

Improve errormsg

See merge request wotsubo/endcap-sl-software-ri-generator!15

CHANGELOG.md

@@ -12,6 +12,10 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - Packagin with Nix flakes (with nixpkgs buildRustPackage) [!16](https://gitlab.cern.ch/wotsubo/endcap-sl-software-ri-generator/-/merge_requests/16)
 - Now xml metadata can be overwritten with corresponding environmental variables. [!17](https://gitlab.cern.ch/wotsubo/endcap-sl-software-ri-generator/-/merge_requests/17)
 
+### Changed
+
+- Improve error message from syn in generator. !15
+
 ## [0.3.1] - 2025-04-11
 
 ### Changed

src/generator.rs

@@ -26,8 +26,12 @@ use thiserror::Error;
 
 #[derive(Debug, Error)]
 pub enum CodeGenError {
-    #[error("tokenization(syn) error")]
-    SynError(#[from] syn::Error),
+    #[error("tokenization(syn) error: {source}: {code}")]
+    SynError {
+        #[source]
+        source: syn::Error,
+        code: String,
+    },
     #[error("failed to create file (name duplicated): {0}")]
     FilePathDuplicatedError(String),
     #[error("parent is required for {module}")]
@@ -42,11 +46,17 @@ mod util {
     use super::CodeGenError;
 
     pub(super) fn parse_to_ident(s: &str) -> Result<proc_macro2::Ident, CodeGenError> {
-        Ok(syn::parse_str(s)?)
+        syn::parse_str(s).map_err(|e| CodeGenError::SynError {
+            source: e,
+            code: s.to_string(),
+        })
     }
 
     pub(super) fn parse_to_literal(s: &str) -> Result<proc_macro2::Literal, CodeGenError> {
-        Ok(syn::parse_str(s)?)
+        syn::parse_str(s).map_err(|e| CodeGenError::SynError {
+            source: e,
+            code: s.to_string(),
+        })
     }
 
     // currently only U32 is used, so `dead_code` for Debug, PartialEq
@@ -161,10 +171,9 @@ This code is auto generated using endcap_sl_software_ri_generator.
             GENERATOR_GIT_SHA,
         );
         let files = self.generate_register_interface(None, None, HashMap::new())?;
-        Ok(files
+        files
             .into_iter()
-            .map(
-                |(path, tokens)| -> Result<(PathBuf, syn::File), syn::Error> {
+            .map(|(path, tokens)| -> Result<(PathBuf, syn::File), _> {
                 let tokens = if path
                     .file_name()
                     .is_some_and(|file| file == "register_interface.rs")
@@ -177,11 +186,14 @@ This code is auto generated using endcap_sl_software_ri_generator.
                 } else {
                     tokens
                 };
-                    let file: syn::File = syn::parse2(tokens)?;
+                let file: syn::File =
+                    syn::parse2(tokens.clone()).map_err(|e| CodeGenError::SynError {
+                        source: e,
+                        code: tokens.to_string(),
+                    })?;
                 Ok((path, file))
-                },
-            )
-            .process_results(|kv| HashMap::from_iter(kv))?)
+            })
+            .process_results(|kv| HashMap::from_iter(kv))
     }
 }