Collecting multiple attribute error (#4243)

* collecting multiple errors

* collecting errors from different fileds

* adding changelog

* Adding UI test

* refactoring

* Update pyo3-macros-backend/src/attributes.rs

Co-authored-by: David Hewitt <mail@davidhewitt.dev>

* Update newsfragments/4243.changed.md

Co-authored-by: David Hewitt <mail@davidhewitt.dev>

* Update tests/ui/invalid_pyclass_args.rs

Co-authored-by: David Hewitt <mail@davidhewitt.dev>

* using pural for names

* get rid of internidiate field_options_res

* reset ordering

---------

Co-authored-by: David Hewitt <mail@davidhewitt.dev>

newsfragments/4243.changed.md

@@ -0,0 +1 @@
+Report multiple errors from `#[pyclass]` and `#[pyo3(..)]` attributes.

pyo3-macros-backend/src/attributes.rs

@@ -384,13 +384,41 @@ pub fn take_attributes(
 
 pub fn take_pyo3_options<T: Parse>(attrs: &mut Vec<syn::Attribute>) -> Result<Vec<T>> {
     let mut out = Vec::new();
-    take_attributes(attrs, |attr| {
-        if let Some(options) = get_pyo3_options(attr)? {
-            out.extend(options);
+    let mut all_errors = ErrorCombiner(None);
+    take_attributes(attrs, |attr| match get_pyo3_options(attr) {
+        Ok(result) => {
+            if let Some(options) = result {
+                out.extend(options);
+                Ok(true)
+            } else {
+                Ok(false)
+            }
+        }
+        Err(err) => {
+            all_errors.combine(err);
             Ok(true)
-        } else {
-            Ok(false)
         }
     })?;
+    all_errors.ensure_empty()?;
     Ok(out)
 }
+
+pub struct ErrorCombiner(pub Option<syn::Error>);
+
+impl ErrorCombiner {
+    pub fn combine(&mut self, error: syn::Error) {
+        if let Some(existing) = &mut self.0 {
+            existing.combine(error);
+        } else {
+            self.0 = Some(error);
+        }
+    }
+
+    pub fn ensure_empty(self) -> Result<()> {
+        if let Some(error) = self.0 {
+            Err(error)
+        } else {
+            Ok(())
+        }
+    }
+}

pyo3-macros-backend/src/pyclass.rs

@@ -10,8 +10,9 @@ use syn::{parse_quote, parse_quote_spanned, spanned::Spanned, ImplItemFn, Result
 
 use crate::attributes::kw::frozen;
 use crate::attributes::{
-    self, kw, take_pyo3_options, CrateAttribute, ExtendsAttribute, FreelistAttribute,
-    ModuleAttribute, NameAttribute, NameLitStr, RenameAllAttribute, StrFormatterAttribute,
+    self, kw, take_pyo3_options, CrateAttribute, ErrorCombiner, ExtendsAttribute,
+    FreelistAttribute, ModuleAttribute, NameAttribute, NameLitStr, RenameAllAttribute,
+    StrFormatterAttribute,
 };
 use crate::konst::{ConstAttributes, ConstSpec};
 use crate::method::{FnArg, FnSpec, PyArg, RegularArg};
@@ -252,23 +253,35 @@ pub fn build_py_class(
         )
     );
 
+    let mut all_errors = ErrorCombiner(None);
+
     let mut field_options: Vec<(&syn::Field, FieldPyO3Options)> = match &mut class.fields {
         syn::Fields::Named(fields) => fields
             .named
             .iter_mut()
-            .map(|field| {
-                FieldPyO3Options::take_pyo3_options(&mut field.attrs)
-                    .map(move |options| (&*field, options))
-            })
-            .collect::<Result<_>>()?,
+            .filter_map(
+                |field| match FieldPyO3Options::take_pyo3_options(&mut field.attrs) {
+                    Ok(options) => Some((&*field, options)),
+                    Err(e) => {
+                        all_errors.combine(e);
+                        None
+                    }
+                },
+            )
+            .collect::<Vec<_>>(),
         syn::Fields::Unnamed(fields) => fields
             .unnamed
             .iter_mut()
-            .map(|field| {
-                FieldPyO3Options::take_pyo3_options(&mut field.attrs)
-                    .map(move |options| (&*field, options))
-            })
-            .collect::<Result<_>>()?,
+            .filter_map(
+                |field| match FieldPyO3Options::take_pyo3_options(&mut field.attrs) {
+                    Ok(options) => Some((&*field, options)),
+                    Err(e) => {
+                        all_errors.combine(e);
+                        None
+                    }
+                },
+            )
+            .collect::<Vec<_>>(),
         syn::Fields::Unit => {
             if let Some(attr) = args.options.set_all {
                 return Err(syn::Error::new_spanned(attr, UNIT_SET));
@@ -281,6 +294,8 @@ pub fn build_py_class(
         }
     };
 
+    all_errors.ensure_empty()?;
+
     if let Some(attr) = args.options.get_all {
         for (_, FieldPyO3Options { get, .. }) in &mut field_options {
             if let Some(old_get) = get.replace(Annotated::Struct(attr)) {

tests/ui/invalid_pyclass_args.rs

@@ -1,5 +1,5 @@
-use std::fmt::{Display, Formatter};
 use pyo3::prelude::*;
+use std::fmt::{Display, Formatter};
 
 #[pyclass(extend=pyo3::types::PyDict)]
 struct TypoIntheKey {}
@@ -74,7 +74,16 @@ impl HashOptAndManualHash {
 
 #[pyclass(ord)]
 struct InvalidOrderedStruct {
-    inner: i32
+    inner: i32,
+}
+
+#[pyclass]
+struct MultipleErrors {
+    #[pyo3(foo)]
+    #[pyo3(blah)]
+    x: i32,
+    #[pyo3(pop)]
+    y: i32,
 }
 
 #[pyclass(str)]
@@ -88,9 +97,7 @@ impl Display for StrOptAndManualStr {
 
 #[pymethods]
 impl StrOptAndManualStr {
-    fn __str__(
-        &self,
-    ) -> String {
+    fn __str__(&self) -> String {
         todo!()
     }
 }
@@ -123,45 +130,45 @@ pub struct Point2 {
 #[derive(PartialEq)]
 struct Coord3(u32, u32, u32);
 
-#[pyclass(name = "aaa", str="unsafe: {unsafe_variable}")]
+#[pyclass(name = "aaa", str = "unsafe: {unsafe_variable}")]
 struct StructRenamingWithStrFormatter {
     #[pyo3(name = "unsafe", get, set)]
     unsafe_variable: usize,
 }
 
-#[pyclass(name = "aaa", str="unsafe: {unsafe_variable}")]
+#[pyclass(name = "aaa", str = "unsafe: {unsafe_variable}")]
 struct StructRenamingWithStrFormatter2 {
     unsafe_variable: usize,
 }
 
-#[pyclass(str="unsafe: {unsafe_variable}")]
+#[pyclass(str = "unsafe: {unsafe_variable}")]
 struct StructRenamingWithStrFormatter3 {
     #[pyo3(name = "unsafe", get, set)]
     unsafe_variable: usize,
 }
 
-#[pyclass(rename_all = "SCREAMING_SNAKE_CASE", str="{a_a}, {b_b}, {c_d_e}")]
+#[pyclass(rename_all = "SCREAMING_SNAKE_CASE", str = "{a_a}, {b_b}, {c_d_e}")]
 struct RenameAllVariantsStruct {
     a_a: u32,
     b_b: u32,
     c_d_e: String,
 }
 
-#[pyclass(str="{:?}")]
+#[pyclass(str = "{:?}")]
 #[derive(Debug)]
 struct StructWithNoMember {
     a: String,
     b: String,
 }
 
-#[pyclass(str="{}")]
+#[pyclass(str = "{}")]
 #[derive(Debug)]
 struct StructWithNoMember2 {
     a: String,
     b: String,
 }
 
-#[pyclass(eq, str="Stuff...")]
+#[pyclass(eq, str = "Stuff...")]
 #[derive(Debug, PartialEq)]
 pub enum MyEnumInvalidStrFmt {
     Variant,