Remove duplicate validation (#404)

* Remove duplicated validation of struct attributes

* Fix clippy warnings

* Revert MSRV break

macros/src/types/mod.rs

@@ -39,14 +39,14 @@ fn type_def(attr: &StructAttr, ts_name: Expr, fields: &Fields) -> Result<Derived
 
     match fields {
         Fields::Named(named) => match named.named.len() {
-            0 if attr.tag.is_none() => unit::empty_object(attr, ts_name),
+            0 if attr.tag.is_none() => Ok(unit::empty_object(attr, ts_name)),
             _ => named::named(attr, ts_name, named),
         },
         Fields::Unnamed(unnamed) => match unnamed.unnamed.len() {
-            0 => unit::empty_array(attr, ts_name),
+            0 => Ok(unit::empty_array(attr, ts_name)),
             1 => newtype::newtype(attr, ts_name, unnamed),
             _ => tuple::tuple(attr, ts_name, unnamed),
         },
-        Fields::Unit => unit::null(attr, ts_name),
+        Fields::Unit => Ok(unit::null(attr, ts_name)),
     }
 }

macros/src/types/newtype.rs

@@ -20,7 +20,7 @@ pub(crate) fn newtype(
     let crate_rename = attr.crate_rename();
 
     if field_attr.skip {
-        return super::unit::null(attr, ts_name);
+        return Ok(super::unit::null(attr, ts_name));
     }
 
     let inner_ty = field_attr.type_as(&inner.ty);

macros/src/types/unit.rs

@@ -1,5 +1,5 @@
 use quote::quote;
-use syn::{Expr, Result};
+use syn::Expr;
 
 use crate::{
     attr::{ContainerAttr, StructAttr},
@@ -7,11 +7,10 @@ use crate::{
     DerivedTS,
 };
 
-pub(crate) fn empty_object(attr: &StructAttr, ts_name: Expr) -> Result<DerivedTS> {
-    check_attributes(attr)?;
+pub(crate) fn empty_object(attr: &StructAttr, ts_name: Expr) -> DerivedTS {
     let crate_rename = attr.crate_rename();
 
-    Ok(DerivedTS {
+    DerivedTS {
         crate_rename: crate_rename.clone(),
         inline: quote!("Record<string, never>".to_owned()),
         inline_flattened: None,
@@ -22,14 +21,13 @@ pub(crate) fn empty_object(attr: &StructAttr, ts_name: Expr) -> Result<DerivedTS
         ts_name,
         concrete: attr.concrete.clone(),
         bound: attr.bound.clone(),
-    })
+    }
 }
 
-pub(crate) fn empty_array(attr: &StructAttr, ts_name: Expr) -> Result<DerivedTS> {
-    check_attributes(attr)?;
+pub(crate) fn empty_array(attr: &StructAttr, ts_name: Expr) -> DerivedTS {
     let crate_rename = attr.crate_rename();
 
-    Ok(DerivedTS {
+    DerivedTS {
         crate_rename: crate_rename.clone(),
         inline: quote!("never[]".to_owned()),
         inline_flattened: None,
@@ -40,14 +38,13 @@ pub(crate) fn empty_array(attr: &StructAttr, ts_name: Expr) -> Result<DerivedTS>
         ts_name,
         concrete: attr.concrete.clone(),
         bound: attr.bound.clone(),
-    })
+    }
 }
 
-pub(crate) fn null(attr: &StructAttr, ts_name: Expr) -> Result<DerivedTS> {
-    check_attributes(attr)?;
+pub(crate) fn null(attr: &StructAttr, ts_name: Expr) -> DerivedTS {
     let crate_rename = attr.crate_rename();
 
-    Ok(DerivedTS {
+    DerivedTS {
         crate_rename: crate_rename.clone(),
         inline: quote!("null".to_owned()),
         inline_flattened: None,
@@ -58,17 +55,5 @@ pub(crate) fn null(attr: &StructAttr, ts_name: Expr) -> Result<DerivedTS> {
         ts_name,
         concrete: attr.concrete.clone(),
         bound: attr.bound.clone(),
-    })
-}
-
-fn check_attributes(attr: &StructAttr) -> Result<()> {
-    if attr.rename_all.is_some() {
-        syn_err!("`rename_all` is not applicable to unit structs");
     }
-
-    if attr.tag.is_some() {
-        syn_err!("`tag` is not applicable to unit structs");
-    }
-
-    Ok(())
 }

ts-rs/src/export.rs

@@ -21,7 +21,7 @@ mod path;
 static EXPORT_PATHS: OnceLock<Mutex<HashMap<PathBuf, HashSet<String>>>> = OnceLock::new();
 
 fn get_export_paths<'a>() -> &'a Mutex<HashMap<PathBuf, HashSet<String>>> {
-    EXPORT_PATHS.get_or_init(|| Default::default())
+    EXPORT_PATHS.get_or_init(Default::default)
 }
 
 const NOTE: &str = "// This file was generated by [ts-rs](https://github.com/Aleph-Alpha/ts-rs). Do not edit this file manually.\n";
@@ -201,7 +201,7 @@ fn merge(original_contents: String, new_contents: String) -> String {
         .chain(new_header.lines().skip(1))
         .map(|line| {
             let (import, from) = line.split_once(" from ").unwrap();
-            let path = from.trim_start_matches('"').trim_end_matches(&['"', ';']);
+            let path = from.trim_start_matches('"').trim_end_matches(['"', ';']);
 
             let types = import
                 .trim_start_matches("import type { ")