better parser generation

amqp_codegen/src/main.rs

@@ -1,7 +1,6 @@
 mod parser;
 
 use crate::parser::codegen_parser;
-use anyhow::Result;
 use heck::ToUpperCamelCase;
 use std::fs;
 use strong_xml::XmlRead;
@@ -76,21 +75,21 @@ struct Field {
     asserts: Vec<Assert>,
 }
 
-fn main() -> Result<()> {
+fn main() {
     let content = fs::read_to_string("./amqp-0-9-1.xml").unwrap();
 
-    let amqp = Amqp::from_str(&content)?;
-    codegen(&amqp)
+    let amqp = Amqp::from_str(&content).unwrap();
+    codegen(&amqp);
 }
 
-fn codegen(amqp: &Amqp) -> Result<()> {
+fn codegen(amqp: &Amqp) {
     println!("// This file has been generated by `amqp_codegen`. Do not edit it manually.\n");
-    codegen_domain_defs(amqp)?;
-    codegen_class_defs(amqp)?;
-    codegen_parser(amqp)
+    codegen_domain_defs(amqp);
+    codegen_class_defs(amqp);
+    codegen_parser(amqp);
 }
 
-fn codegen_domain_defs(amqp: &Amqp) -> Result<()> {
+fn codegen_domain_defs(amqp: &Amqp) {
     for domain in &amqp.domains {
         let invariants = invariants(domain.asserts.iter());
 
@@ -103,11 +102,10 @@ fn codegen_domain_defs(amqp: &Amqp) -> Result<()> {
             amqp_type_to_rust_type(&domain.kind),
         );
     }
-
-    Ok(())
 }
 
-fn codegen_class_defs(amqp: &Amqp) -> Result<()> {
+fn codegen_class_defs(amqp: &Amqp) {
+    println!("#[derive(Debug, Clone, PartialEq)]");
     println!("pub enum Class {{");
     for class in &amqp.classes {
         let class_name = class.name.to_upper_camel_case();
@@ -118,6 +116,7 @@ fn codegen_class_defs(amqp: &Amqp) -> Result<()> {
     for class in &amqp.classes {
         let enum_name = class.name.to_upper_camel_case();
         println!("/// Index {}, handler = {}", class.index, class.handler);
+        println!("#[derive(Debug, Clone, PartialEq)]");
         println!("pub enum {enum_name} {{");
         for method in &class.methods {
             let method_name = method.name.to_upper_camel_case();
@@ -127,10 +126,8 @@ fn codegen_class_defs(amqp: &Amqp) -> Result<()> {
                 println!(" {{");
                 for field in &method.fields {
                     let field_name = snake_case(&field.name);
-                    let (field_type, field_docs) = resolve_type(
-                        field.domain.as_ref().or(field.kind.as_ref()).unwrap(),
-                        field.asserts.as_ref(),
-                    )?;
+                    let (field_type, field_docs) =
+                        get_invariants_with_type(field_type(field), field.asserts.as_ref());
                     if !field_docs.is_empty() {
                         println!("        /// {field_docs}");
                     }
@@ -143,8 +140,6 @@ fn codegen_class_defs(amqp: &Amqp) -> Result<()> {
         }
         println!("}}");
     }
-
-    Ok(())
 }
 
 fn amqp_type_to_rust_type(amqp_type: &str) -> &'static str {
@@ -161,13 +156,25 @@ fn amqp_type_to_rust_type(amqp_type: &str) -> &'static str {
     }
 }
 
+fn field_type(field: &Field) -> &String {
+    field.domain.as_ref().or(field.kind.as_ref()).unwrap()
+}
+
+fn resolve_type_from_domain(amqp: &Amqp, domain: &str) -> String {
+    amqp.domains
+        .iter()
+        .find(|d| d.name == domain)
+        .map(|d| d.kind.clone())
+        .unwrap()
+}
+
 /// returns (type name, invariant docs)
-fn resolve_type(domain: &str, asserts: &[Assert]) -> Result<(String, String)> {
+fn get_invariants_with_type(domain: &str, asserts: &[Assert]) -> (String, String) {
     let additional_docs = invariants(asserts.iter());
 
     let type_name = domain.to_upper_camel_case();
 
-    Ok((type_name, additional_docs))
+    (type_name, additional_docs)
 }
 
 fn snake_case(ident: &str) -> String {