Add support for std on containers and variants (fixes #5)

crates/borrowme-macros/src/attr.rs

@@ -32,6 +32,8 @@ pub(crate) struct Container {
     pub(crate) owned_ident: Option<(Span, syn::Ident)>,
     /// Attributes to apply.
     pub(crate) attributes: Attributes,
+    /// Default field type kind.
+    pub(crate) kind: Option<(Span, FieldTypeKind)>,
 }
 
 impl Container {
@@ -53,25 +55,34 @@ pub(crate) fn container(
     let mut attr = Container {
         owned_ident: None,
         attributes: Attributes::default(),
+        kind: None,
     };
 
+    macro_rules! set_attr {
+        ($field:ident $(. $field2:ident)*, $meta:expr, $value:expr, $message:expr $(,)?) => {
+            set_attr(cx, &mut attr.$field$(.$field2)*, $meta, $value, $message)
+        }
+    }
+
     for a in attrs.iter().chain(rest) {
         let result = if a.path().is_ident(BORROWME) {
             a.parse_nested_meta(|meta| {
+                let span = meta.path.span();
+
                 if meta.path.is_ident("name") {
                     meta.input.parse::<Token![=]>()?;
-                    set_attr(
-                        cx,
-                        &mut attr.owned_ident,
-                        meta.path.span(),
-                        meta.input.parse()?,
-                        "Duplicate name.",
-                    );
+                    set_attr!(owned_ident, span, meta.input.parse()?, "Duplicate name.",);
+                    return Ok(());
+                }
+
+                if meta.path.is_ident("std") {
+                    let kind = FieldTypeKind::Std;
+                    set_attr!(kind, span, kind, "Duplicate container field kind.");
                     return Ok(());
                 }
 
                 Err(syn::Error::new(
-                    meta.path.span(),
+                    span,
                     format_args!("#[{BORROWME}]: Unsupported attribute."),
                 ))
             })
@@ -99,19 +110,39 @@ pub(crate) fn container(
 
 pub(crate) struct Variant {
     pub(crate) attributes: Attributes,
+    pub(crate) kind: Option<(Span, FieldTypeKind)>,
 }
 
 /// Parse variant attributes.
-pub(crate) fn variant(cx: &Ctxt, attrs: &[syn::Attribute]) -> Result<Variant, ()> {
+pub(crate) fn variant(
+    cx: &Ctxt,
+    attrs: &[syn::Attribute],
+    container: &Container,
+) -> Result<Variant, ()> {
     let mut variant = Variant {
         attributes: Attributes::default(),
+        kind: None,
     };
 
+    macro_rules! set_attr {
+        ($field:ident $(. $field2:ident)*, $meta:expr, $value:expr, $message:expr $(,)?) => {
+            set_attr(cx, &mut variant.$field$(.$field2)*, $meta, $value, $message)
+        }
+    }
+
     for a in attrs {
         let result = if a.path().is_ident(BORROWME) {
             a.parse_nested_meta(|meta| {
+                let span = meta.path.span();
+
+                if meta.path.is_ident("std") {
+                    let kind = FieldTypeKind::Std;
+                    set_attr!(kind, span, kind, "Duplicate variant field kind.");
+                    return Ok(());
+                }
+
                 Err(syn::Error::new(
-                    meta.path.span(),
+                    span,
                     format_args!("#[{BORROWME}]: Unsupported attribute."),
                 ))
             })
@@ -134,6 +165,10 @@ pub(crate) fn variant(cx: &Ctxt, attrs: &[syn::Attribute]) -> Result<Variant, ()
         }
     }
 
+    if variant.kind.is_none() {
+        variant.kind = container.kind;
+    }
+
     Ok(variant)
 }
 
@@ -219,7 +254,12 @@ impl Field {
 /// We provide `field_spans` so that the processed `FieldType::Type` can be
 /// respanned to emit better diagnostics in case if fails something like a type
 /// check.
-pub(crate) fn field(cx: &Ctxt, spans: (Span, Span), attrs: &[syn::Attribute]) -> Result<Field, ()> {
+pub(crate) fn field(
+    cx: &Ctxt,
+    spans: (Span, Span),
+    attrs: &[syn::Attribute],
+    default_kind: Option<(Span, FieldTypeKind)>,
+) -> Result<Field, ()> {
     let mut attr = Field {
         is_mut: None,
         ty: FieldType::default(),
@@ -376,6 +416,10 @@ pub(crate) fn field(cx: &Ctxt, spans: (Span, Span), attrs: &[syn::Attribute]) ->
         }
     }
 
+    if attr.ty.kind.is_none() {
+        attr.ty.kind = default_kind;
+    }
+
     Ok(attr)
 }
 

crates/borrowme-macros/src/implement.rs

@@ -188,6 +188,7 @@ pub(crate) fn implement(
             process_fields(
                 cx,
                 Access::SelfAccess,
+                attr.kind,
                 &mut o_st.fields,
                 &mut b_st.fields,
                 &mut to_owned_entries,
@@ -250,7 +251,7 @@ pub(crate) fn implement(
             let borrow_ident = b_en.ident.clone();
 
             for (o_variant, b_variant) in o_en.variants.iter_mut().zip(b_en.variants.iter_mut()) {
-                let attr = attr::variant(cx, &o_variant.attrs)?;
+                let attr = attr::variant(cx, &o_variant.attrs, &attr)?;
                 attr::strip([&mut o_variant.attrs, &mut b_variant.attrs]);
 
                 apply_attributes(&attr.attributes, &mut o_variant.attrs, &mut b_variant.attrs);
@@ -261,6 +262,7 @@ pub(crate) fn implement(
                 process_fields(
                     cx,
                     Access::BindingAccess,
+                    attr.kind,
                     &mut o_variant.fields,
                     &mut b_variant.fields,
                     &mut to_owned_entries,
@@ -419,6 +421,7 @@ pub(crate) fn implement(
 fn process_fields(
     cx: &Ctxt,
     access: Access,
+    default_kind: Option<(Span, attr::FieldTypeKind)>,
     o_fields: &mut syn::Fields,
     b_fields: &mut syn::Fields,
     to_owned_entries: &mut Vec<syn::FieldValue>,
@@ -428,7 +431,7 @@ fn process_fields(
     for (index, (o_field, b_field)) in o_fields.iter_mut().zip(b_fields.iter_mut()).enumerate() {
         let field_ty_spans = field_ty_spans(o_field);
 
-        let mut attr = attr::field(cx, field_ty_spans, &o_field.attrs)?;
+        let mut attr = attr::field(cx, field_ty_spans, &o_field.attrs, default_kind)?;
         attr::strip([&mut o_field.attrs, &mut b_field.attrs]);
         apply_attributes(&attr.attributes, &mut o_field.attrs, &mut b_field.attrs);
 

crates/borrowme-macros/src/lib.rs

@@ -2,6 +2,8 @@
 //! [<img alt="crates.io" src="https://img.shields.io/crates/v/borrowme-macros.svg?style=for-the-badge&color=fc8d62&logo=rust" height="20">](https://crates.io/crates/borrowme-macros)
 //! [<img alt="docs.rs" src="https://img.shields.io/badge/docs.rs-borrowme--macros-66c2a5?style=for-the-badge&logoColor=white&logo=data:image/svg+xml;base64,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" height="20">](https://docs.rs/borrowme-macros)
 
+#![allow(clippy::too_many_arguments)]
+
 mod attr;
 mod ctxt;
 mod implement;

crates/borrowme/src/lib.rs

@@ -223,6 +223,9 @@
 ///
 /// This section documents supported container attributes:
 ///
+/// * [`#[borrowme(std)]`][container-std] which acts as if
+///   [`#[borrowme(std)]`][std] is applied to every field and variant in the
+///   container by default.
 /// * [`#[borrowme(name = <ident>)]`][name] which is used to change the name of
 ///   the generated *owned* variant.
 /// * [`#[borrowed_attr(<meta>)]`][b-c] and [`#[owned_attr(<meta>)]`][o-c] which
@@ -250,6 +253,37 @@
 ///
 /// <br>
 ///
+/// #### `#[borrowme(std)]` container attribute
+///
+/// This container attribute acts as if [`#[borrowme(std)]`][std] is applied to
+/// every field or variant in the container.
+///
+/// Note that this defeats copy and reference heuristics.
+///
+/// ```
+/// use borrowme::borrowme;
+///
+/// #[borrowme]
+/// #[borrowme(std)]
+/// struct StdStruct<'a> {
+///     a: &'a String,
+///     #[borrowme(copy)]
+///     b: u32,
+/// }
+///
+/// #[borrowme]
+/// #[borrowme(std)]
+/// enum StdEnum<'a> {
+///     Variant {
+///         a: &'a String,
+///         #[borrowme(copy)]
+///         b: u32,
+///     }
+/// }
+/// ```
+///
+/// <br>
+///
 /// #### `#[borrowme(name = <ident>)]` container attribute
 ///
 /// This allows you to pick the name to use for the generated type. By default
@@ -328,6 +362,9 @@
 ///
 /// * [`#[borrowed_attr(<meta>)]`][b-v] and [`#[owned_attr(<meta>)]`][o-v] which
 ///   are used to add custom attributes.
+/// * [`#[borrowme(std)]`][variant-std] which acts as if
+///   [`#[borrowme(std)]`][std] is applied to every field in the variant by
+///   default.
 ///
 /// Variant attributes are attributes which apply to `enum` variants.
 ///
@@ -375,6 +412,32 @@
 ///
 /// <br>
 ///
+/// #### `#[borrowme(std)]` variant attribute
+///
+/// This container attribute acts as if [`#[borrowme(std)]`][std] is applied to
+/// every field inside of a variant.
+///
+/// Note that this defeats copy and reference heuristics.
+///
+/// ```
+/// use borrowme::borrowme;
+///
+/// #[borrowme]
+/// enum StdEnum<'a> {
+///     #[borrowme(std)]
+///     Variant {
+///         a: &'a String,
+///         #[borrowme(copy)]
+///         b: u32,
+///     }
+/// }
+/// ```
+///
+/// <br>
+///
+///
+/// <br>
+///
 /// ## Field attributes
 ///
 /// This section documents supported field attributes:
@@ -756,20 +819,22 @@
 /// }
 /// ```
 ///
-/// [name]: #borrowmename--ident-container-attribute
 /// [b-c]: #borrowed_attrmeta-container-attribute
-/// [o-c]: #owned_attrmeta-container-attribute
+/// [b-f]: #borrowed_attrmeta-field-attribute
 /// [b-v]: #borrowed_attrmeta-variant-attribute
-/// [o-v]: #owned_attrmeta-variant-attribute
-/// [owned]: #ownedtype-or-borrowmeowned--type-field-attributes
-/// [to_owned_with]: #borrowmeto_owned_with--path-field-attribute
 /// [borrow_with]: #borrowmeborrow_with--path-field-attribute
-/// [with]: #borrowmewith--path-field-attribute
+/// [container-std]: #borrowmestd-container-attribute
 /// [copy]: #copy-and-no_copy-field-attribute
-/// [std]: #borrowmestd-field-attribute
 /// [mut]: #borrowmemut-field-attribute
-/// [b-f]: #borrowed_attrmeta-field-attribute
+/// [name]: #borrowmename--ident-container-attribute
+/// [o-c]: #owned_attrmeta-container-attribute
 /// [o-f]: #owned_attrmeta-field-attribute
+/// [o-v]: #owned_attrmeta-variant-attribute
+/// [owned]: #ownedtype-or-borrowmeowned--type-field-attributes
+/// [std]: #borrowmestd-field-attribute
+/// [to_owned_with]: #borrowmeto_owned_with--path-field-attribute
+/// [variant-std]: #borrowmestd-variant-attribute
+/// [with]: #borrowmewith--path-field-attribute
 #[doc(inline)]
 pub use borrowme_macros::borrowme;
 

crates/borrowme/tests/std_containers.rs

@@ -0,0 +1,32 @@
+use borrowme::borrowme;
+
+#[borrowme]
+#[borrowme(std)]
+#[derive(Clone)]
+struct StdStruct<'a> {
+    a: &'a String,
+    #[borrowme(copy)]
+    b: u32,
+}
+
+#[borrowme]
+#[borrowme(std)]
+#[derive(Clone)]
+enum StdOnEnum<'a> {
+    Variant {
+        a: &'a String,
+        #[borrowme(copy)]
+        b: u32,
+    },
+}
+
+#[borrowme]
+#[derive(Clone)]
+enum StdVariant<'a> {
+    #[borrowme(std)]
+    Variant {
+        a: &'a String,
+        #[borrowme(copy)]
+        b: u32,
+    },
+}