Add some doc comments

schemars_derive/src/attr/validation.rs

@@ -22,7 +22,6 @@ pub struct ValidationAttrs {
 
 impl ValidationAttrs {
     pub fn new(attrs: &[syn::Attribute], errors: &Ctxt) -> Self {
-        // TODO allow setting "validate" attributes through #[schemars(...)]
         ValidationAttrs::default()
             .populate(attrs, "schemars", false, errors)
             .populate(attrs, "validate", true, errors)

schemars_derive/src/schema_exprs.rs

@@ -489,11 +489,7 @@ fn expr_for_struct(
         .map(|field| {
             let (ty, type_def) = type_for_field_schema(field);
 
-            let required = if field.validation_attrs.required {
-                quote!(Some(true))
-            } else {
-                quote!(None)
-            };
+            let required = field.validation_attrs.required;
 
             let args = quote!(gen, #required);
             let mut schema_expr = quote_spanned! {ty.span()=>