From eb4613f02a14e4659d9bebd6ee9d3183d97c0cd6 Mon Sep 17 00:00:00 2001
From: Callum Cunha <callum.cunha@gmail.com>
Date: Sat, 23 Dec 2023 07:03:23 +0000
Subject: [PATCH] feat: carry over field docs

---
 src/lib.rs    | 11 +++++++++++
 src/patch.rs  | 19 ++++++++++++++-----
 src/view.rs   | 10 +++++++---
 tests/view.rs |  4 ++++
 4 files changed, 36 insertions(+), 8 deletions(-)

diff --git a/src/lib.rs b/src/lib.rs
index f2cf2ee..0f9e1bd 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -209,6 +209,17 @@ fn extract_oai_f_attributes(attrs: &[syn::Attribute]) -> Vec<&syn::Attribute> {
         .collect()
 }
 
+fn is_doc(v: &&Attribute) -> bool {
+    v.meta.require_name_value().map_or(false, |v| {
+        v.path.segments.first().map_or(false, |v| v.ident == "doc")
+    })
+}
+
+fn extract_docs(attrs: &[Attribute]) -> proc_macro2::TokenStream {
+    let docs: Vec<_> = attrs.iter().filter(is_doc).collect();
+    quote!(#(#docs)*)
+}
+
 /// Aborts on unexpected args to show that they arent valid
 fn abort_unexpected_args(names: Vec<&str>, args: &[TokenTree]) {
     for tk in args.iter() {
diff --git a/src/patch.rs b/src/patch.rs
index d3bd893..7b1d47b 100644
--- a/src/patch.rs
+++ b/src/patch.rs
@@ -1,9 +1,9 @@
 use crate::*;
 
 use proc_macro2::{Group, Ident, TokenStream, TokenTree};
+use proc_macro_error::abort;
 use quote::quote;
 use syn::{Attribute, DeriveInput, Type};
-use proc_macro_error::abort;
 
 struct PatchModelArgs {
     name: Ident,
@@ -40,7 +40,7 @@ pub fn impl_patch_model(
             }
 
             // Add
-            let field_ty = &field.ty;
+            let docs = extract_docs(&field.attrs);
             let oai_f_attributes: Vec<_> = field_attributes
                 .iter()
                 .filter(|attr| {
@@ -51,6 +51,7 @@ pub fn impl_patch_model(
                         .map_or(false, |seg| seg.ident == "oai")
                 })
                 .collect();
+            let field_ty = &field.ty;
             let option_ty = extract_type_from_option(field_ty);
 
             fields_and_is_option.push((field_name, option_ty.is_some()));
@@ -58,6 +59,7 @@ pub fn impl_patch_model(
                 field_name,
                 field_ty,
                 option_ty,
+                &docs,
                 &oai_f_attributes,
             ));
         }),
@@ -216,6 +218,7 @@ fn impl_struct_fields(
     field_name: &Ident,
     field_ty: &Type,
     #[allow(unused_variables)] option_ty: Option<&Type>,
+    docs: &TokenStream,
     oai_f_attr: &Vec<&Attribute>,
 ) -> TokenStream {
     #[cfg(feature = "openapi")]
@@ -223,12 +226,14 @@ fn impl_struct_fields(
         match option_ty {
             Some(t) => {
                 quote! {
-                   #(#oai_f_attr)*
-                   pub #field_name: ::poem_openapi::types::MaybeUndefined<#t>
+                    #docs
+                    #(#oai_f_attr)*
+                    pub #field_name: ::poem_openapi::types::MaybeUndefined<#t>
                 }
             }
             _ => {
                 quote! {
+                    #docs
                     #(#oai_f_attr)*
                     pub #field_name: core::option::Option<#field_ty>
                 }
@@ -238,6 +243,7 @@ fn impl_struct_fields(
     #[cfg(not(feature = "openapi"))]
     {
         quote! {
+            #docs
             #(#oai_f_attr)*
             pub #field_name: core::option::Option<#field_ty>
         }
@@ -257,7 +263,10 @@ fn parse_patch_arg(attr: &Attribute) -> PatchModelArgs {
     let name = match &tks[0] {
         TokenTree::Ident(v) => v.clone(),
         x => {
-            abort!(x, "First argument must be an identifier (name) of the struct for the view")
+            abort!(
+                x,
+                "First argument must be an identifier (name) of the struct for the view"
+            )
         }
     };
 
diff --git a/src/view.rs b/src/view.rs
index 00b22de..40a61ba 100644
--- a/src/view.rs
+++ b/src/view.rs
@@ -36,14 +36,16 @@ pub fn impl_view_model(
                 let field_attr: &Vec<syn::Attribute> = &field.attrs;
 
                 let vis = &field.vis;
+                let docs = extract_docs(&field.attrs);
+                let oai_f_attributes: Vec<_> = extract_oai_f_attributes(field_attr);
                 let field_name = &field.ident.as_ref().unwrap();
                 let field_ty = &field.ty;
-                let oai_f_attributes: Vec<_> = extract_oai_f_attributes(field_attr);
 
                 field_from_mapping.push(quote!(#field_name: value.#field_name));
                 quote! {
-                   #(#oai_f_attributes)*
-                   #vis #field_name: #field_ty
+                    #docs
+                    #(#oai_f_attributes)*
+                    #vis #field_name: #field_ty
                 }
             })
             .collect(),
@@ -58,6 +60,7 @@ pub fn impl_view_model(
                     let mut field_without_attrs = field.clone();
                     field_without_attrs.attrs = vec![];
 
+                    let docs = extract_docs(&field.attrs);
                     let field_name = &field.ident;
 
                     match &field.fields {
@@ -99,6 +102,7 @@ pub fn impl_view_model(
                     };
                     
                     quote! {
+                        #docs
                         #(#oai_f_attr)*
                         #field_without_attrs
                     }
diff --git a/tests/view.rs b/tests/view.rs
index 67c1c48..1c10d5f 100644
--- a/tests/view.rs
+++ b/tests/view.rs
@@ -8,7 +8,9 @@ use restructed::Models;
 #[derive(Models)]
 #[view(UserProfile, fields(display_name, bio))]
 struct User {
+    /// This should be omitted
     id: i32,
+    /// This shouldn't be omitted
     display_name: String,
     bio: String,
     password: String,
@@ -53,6 +55,8 @@ fn only_fields() {
 #[derive(Debug, Clone, Models)]
 #[view(ApiErrorReads, fields(NotFound, Unauthorized, InternalServerError))]
 pub enum ApiError {
+    /// This "NotFound" rustdoc will carry over <br/>
+    /// Even for multiple lines
     NotFound(String),
     ConflictX(String),
     ConflictY(u64),