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#![allow(deprecated)]
use proc_macro2::{Ident, Span};
use syn::{Expr, ExprLit, Field, Lit};
use crate::{
ALIAS, ALIAS_DEPRECATED, ALLOW, ARGS, EXCEPT, EXTEND, EXTEND_DEPRECATED, GETTER, GETTER_INLINE,
GETTER_PREFIX, GETTER_PREFIX_DEFAULT, GETTER_VISIBILITY, INLINE, INTO_PREFIX, SETTER,
SETTER_INLINE, SETTER_PREFIX, SETTER_PREFIX_DEFAULT, SETTER_VISIBILITY, SKIP, VISIBILITY,
};
#[derive(Debug)]
pub(crate) struct Rules {
pub alias: Option<Ident>,
pub inc_for_vec: bool,
pub prefix_setter: String,
pub prefix_getter: String,
pub gen_getter: bool,
pub gen_setter: bool,
pub gen_into: bool,
pub into_prefix: Option<String>,
pub getter_visibility: Option<String>,
pub setter_visibility: Option<String>,
pub getter_inline: Option<InlineMode>,
pub setter_inline: Option<InlineMode>,
}
#[derive(Debug, Clone, Copy, PartialEq)]
pub(crate) enum InlineMode {
None, // No inline attribute
Default, // #[inline]
Always, // #[inline(always)]
}
impl Default for Rules {
fn default() -> Self {
Self {
alias: None,
inc_for_vec: false,
prefix_setter: SETTER_PREFIX_DEFAULT.into(),
prefix_getter: String::new(), // Empty for named structs, will use "nth" for tuple structs
gen_getter: true,
gen_setter: true,
gen_into: true,
into_prefix: None, // Default: "into"
getter_visibility: None, // Default: pub
setter_visibility: None, // Default: pub
getter_inline: Some(InlineMode::Always), // Default: #[inline(always)] for getters
setter_inline: Some(InlineMode::Default), // Default: #[inline] for setters
}
}
}
impl From<&Field> for Rules {
fn from(field: &Field) -> Self {
let mut rules = Rules::default();
if let Some(attr) = field.attrs.first() {
if attr.path().is_ident(ARGS) {
if let Err(err) = attr.parse_nested_meta(|meta| {
match meta.path.get_ident().map(|i| i.to_string()).as_deref() {
Some(GETTER) => {
rules.gen_getter = meta
.value()
.map(|v| v.parse::<Expr>().map(|e| Rules::parse_bool_or_str(&e)))
.unwrap_or(Ok(true))
.unwrap_or(true);
}
Some(SETTER) => {
rules.gen_setter = meta
.value()
.map(|v| v.parse::<Expr>().map(|e| Rules::parse_bool_or_str(&e)))
.unwrap_or(Ok(true))
.unwrap_or(true);
}
Some(SKIP) => {
let skip = meta
.value()
.map(|v| v.parse::<Expr>().map(|e| Rules::parse_bool_or_str(&e)))
.unwrap_or(Ok(true))
.unwrap_or(true);
rules.gen_getter = !skip;
rules.gen_setter = !skip;
}
Some(EXTEND) | Some(EXTEND_DEPRECATED) => {
rules.inc_for_vec = meta
.value()
.map(|v| v.parse::<Expr>().map(|e| Rules::parse_bool_or_str(&e)))
.unwrap_or(Ok(true))
.unwrap_or(true);
}
Some(ALIAS) | Some(ALIAS_DEPRECATED) => {
let expr = meta.value()?.parse::<Expr>()?;
if let Expr::Lit(ExprLit {
lit: Lit::Str(s), ..
}) = expr
{
rules.alias = Some(Ident::new(&s.value(), s.span()));
} else {
return Err(meta.error("Expected a string literal for alias"));
}
}
Some(SETTER_PREFIX) => {
if let Ok(Expr::Lit(ExprLit {
lit: Lit::Str(s), ..
})) = meta.value().and_then(|v| v.parse::<Expr>())
{
let value = s.value();
// setter_prefix cannot be empty, use default if empty
rules.prefix_setter = if value.is_empty() {
SETTER_PREFIX_DEFAULT.into()
} else {
value
};
} else {
return Err(
meta.error("Expected a string literal for setter_prefix")
);
}
}
Some(GETTER_PREFIX) => {
if let Ok(Expr::Lit(ExprLit {
lit: Lit::Str(s), ..
})) = meta.value().and_then(|v| v.parse::<Expr>())
{
rules.prefix_getter = s.value();
} else {
return Err(
meta.error("Expected a string literal for getter_prefix")
);
}
}
Some(INTO_PREFIX) => {
if let Ok(Expr::Lit(ExprLit {
lit: Lit::Str(s), ..
})) = meta.value().and_then(|v| v.parse::<Expr>())
{
rules.into_prefix = Some(s.value());
} else {
return Err(meta.error("Expected a string literal for into_prefix"));
}
}
Some(GETTER_VISIBILITY) => {
if let Ok(Expr::Lit(ExprLit {
lit: Lit::Str(s), ..
})) = meta.value().and_then(|v| v.parse::<Expr>())
{
let vis = s.value();
rules.getter_visibility = Some(Rules::parse_visibility(&vis));
} else {
return Err(
meta.error("Expected a string literal for getter_visibility")
);
}
}
Some(SETTER_VISIBILITY) => {
if let Ok(Expr::Lit(ExprLit {
lit: Lit::Str(s), ..
})) = meta.value().and_then(|v| v.parse::<Expr>())
{
let vis = s.value();
rules.setter_visibility = Some(Rules::parse_visibility(&vis));
} else {
return Err(
meta.error("Expected a string literal for setter_visibility")
);
}
}
Some(INLINE) => {
// Parse inline for both getter and setter
let inline_mode = Rules::parse_inline_value(&meta)?;
rules.getter_inline = Some(inline_mode);
rules.setter_inline = Some(inline_mode);
}
Some(GETTER_INLINE) => {
rules.getter_inline = Some(Rules::parse_inline_value(&meta)?);
}
Some(SETTER_INLINE) => {
rules.setter_inline = Some(Rules::parse_inline_value(&meta)?);
}
Some(ALLOW) => {
meta.parse_nested_meta(|nested| {
if let Some(ident) = nested.path.get_ident() {
match ident.to_string().as_str() {
GETTER => rules.gen_getter = true,
SETTER => rules.gen_setter = true,
SKIP => {
rules.gen_getter = false;
rules.gen_setter = false;
}
EXTEND | EXTEND_DEPRECATED => rules.inc_for_vec = true,
_ => return Err(nested.error("Unsupported allow argument")),
}
}
Ok(())
})?;
}
Some(EXCEPT) => {
meta.parse_nested_meta(|nested| {
if let Some(ident) = nested.path.get_ident() {
match ident.to_string().as_str() {
GETTER => rules.gen_getter = false,
SETTER => rules.gen_setter = false,
SKIP => {
rules.gen_getter = true;
rules.gen_setter = true;
}
EXTEND | EXTEND_DEPRECATED => rules.inc_for_vec = false,
"into" => rules.gen_into = false,
_ => {
return Err(nested.error("Unsupported except argument"))
}
}
}
Ok(())
})?;
}
Some(VISIBILITY) => {
if let Ok(Expr::Lit(ExprLit {
lit: Lit::Str(s), ..
})) = meta.value().and_then(|v| v.parse::<Expr>())
{
let vis = s.value();
let vis_val = Rules::parse_visibility(&vis);
rules.getter_visibility = Some(vis_val.clone());
rules.setter_visibility = Some(vis_val);
} else {
return Err(meta.error("Expected a string literal for visibility"));
}
}
_ => return Err(meta.error("Unsupported argument")),
}
Ok(())
}) {
panic!("Failed to parse attribute: {err}");
}
}
}
rules
}
}
impl Rules {
pub fn parse_bool_or_str(value: &Expr) -> bool {
match value {
Expr::Lit(lit) => match &lit.lit {
Lit::Bool(x) => x.value,
Lit::Str(x) => matches!(
x.value().to_lowercase().as_str(),
"yes" | "true" | "t" | "y"
),
_ => false,
},
_ => false,
}
}
/// Parse visibility keyword to full visibility string
/// Supports: "pub", "public", "private", "pub(crate)", "pub(self)", "pub(super)"
pub fn parse_visibility(vis: &str) -> String {
match vis.to_lowercase().as_str() {
"pub" | "public" => "pub".to_string(),
"private" => "".to_string(), // Empty means private
"crate" => "pub(crate)".to_string(),
"self" => "pub(self)".to_string(),
"super" => "pub(super)".to_string(),
_ if vis.starts_with("pub(") => vis.to_string(), // pub(crate), pub(self), pub(super), pub(in path)
_ => vis.to_string(), // Preserve as-is for full syntax
}
}
/// Generates visibility tokens for getter methods
pub fn getter_visibility_token(&self) -> proc_macro2::TokenStream {
Rules::visibility_token_impl(&self.getter_visibility)
}
/// Generates visibility tokens for setter methods
pub fn setter_visibility_token(&self) -> proc_macro2::TokenStream {
Rules::visibility_token_impl(&self.setter_visibility)
}
/// Internal implementation for generating visibility tokens
fn visibility_token_impl(vis_option: &Option<String>) -> proc_macro2::TokenStream {
use proc_macro2::TokenStream;
use quote::quote;
match vis_option {
Some(vis) if vis.is_empty() => {
// Private (no pub)
TokenStream::new()
}
Some(vis) => {
// Parse the visibility string to generate tokens
match vis.as_str() {
"pub" => quote! { pub },
"pub(crate)" => quote! { pub(crate) },
"pub(self)" => quote! { pub(self) },
"pub(super)" => quote! { pub(super) },
vis if vis.starts_with("pub(in ") => {
// Handle pub(in path::to::module)
let path_str = vis.strip_prefix("pub(in ").unwrap();
let path_str = path_str.strip_suffix(')').unwrap_or(path_str);
let path: syn::Path = syn::parse_str(path_str)
.unwrap_or_else(|_| panic!("Invalid visibility path: {vis}"));
quote! { pub(in #path) }
}
_ => quote! { pub }, // Default to pub
}
}
None => {
// Default to pub
quote! { pub }
}
}
}
/// Parse inline attribute value
/// Supports: #[args(inline)], #[args(inline = true)], #[args(inline = "always")]
pub fn parse_inline_value(meta: &syn::meta::ParseNestedMeta) -> syn::Result<InlineMode> {
// Try to parse value
if let Ok(value) = meta.value() {
let expr = value.parse::<Expr>()?;
match expr {
Expr::Lit(ExprLit {
lit: Lit::Bool(b), ..
}) => {
if b.value {
Ok(InlineMode::Default)
} else {
Ok(InlineMode::None)
}
}
Expr::Lit(ExprLit {
lit: Lit::Str(s), ..
}) => {
match s.value().to_lowercase().as_str() {
"always" => Ok(InlineMode::Always),
"true" | "yes" | "default" => Ok(InlineMode::Default),
"false" | "no" | "none" => Ok(InlineMode::None),
_ => Err(meta
.error("Expected 'always', 'true', 'false', or no value for inline")),
}
}
_ => Err(meta.error("Expected a boolean or string for inline")),
}
} else {
// No value means #[args(inline)] -> default inline
Ok(InlineMode::Default)
}
}
/// Generate inline attribute tokens for getter
pub fn getter_inline_token(&self) -> proc_macro2::TokenStream {
Rules::inline_token_impl(&self.getter_inline)
}
/// Generate inline attribute tokens for setter
pub fn setter_inline_token(&self) -> proc_macro2::TokenStream {
Rules::inline_token_impl(&self.setter_inline)
}
/// Internal implementation for generating inline tokens
fn inline_token_impl(inline_option: &Option<InlineMode>) -> proc_macro2::TokenStream {
use proc_macro2::TokenStream;
use quote::quote;
match inline_option {
Some(InlineMode::Always) => quote! { #[inline(always)] },
Some(InlineMode::Default) => quote! { #[inline] },
Some(InlineMode::None) | None => TokenStream::new(),
}
}
pub fn generate_setter_getter_names(&self, field: &Field, idx: usize) -> (Ident, Ident) {
match &field.ident {
None => {
// Tuple struct: for getter, if prefix is empty and no alias, use "nth" as default
let actual_getter_prefix = if self.prefix_getter.is_empty() && self.alias.is_none()
{
GETTER_PREFIX_DEFAULT
} else {
&self.prefix_getter
};
match &self.alias {
// Tuple struct with alias
Some(alias) => {
// setter_prefix is never empty (enforced in parsing)
let setter_name = format!("{}_{}", self.prefix_setter, alias);
let setter_name = Ident::new(&setter_name, Span::call_site());
// getter: if prefix is empty, use alias directly; otherwise prefix_alias
let getter_name = if actual_getter_prefix.is_empty() {
format!("{alias}")
} else {
format!("{actual_getter_prefix}_{alias}")
};
let getter_name = Ident::new(&getter_name, Span::call_site());
(setter_name, getter_name)
}
None => {
// Tuple struct without alias: use index
// setter_prefix is never empty (enforced in parsing)
let setter_name = format!("{}_{}", self.prefix_setter, idx);
let setter_name = Ident::new(&setter_name, Span::call_site());
// getter: use actual_getter_prefix (which defaults to "nth" for tuple structs)
let getter_name = format!("{actual_getter_prefix}_{idx}");
let getter_name = Ident::new(&getter_name, Span::call_site());
(setter_name, getter_name)
}
}
}
Some(ident) => {
// Named struct
let name_or_alias = self.alias.as_ref().unwrap_or(ident);
// setter: always use prefix (prefix is never empty)
let setter_name = format!("{}_{}", self.prefix_setter, name_or_alias);
let setter_name = Ident::new(&setter_name, Span::call_site());
// getter: if prefix is empty, use name/alias directly; otherwise prefix_name
let getter_name = if self.prefix_getter.is_empty() {
format!("{name_or_alias}")
} else {
format!("{}_{}", self.prefix_getter, name_or_alias)
};
let getter_name = Ident::new(&getter_name, Span::call_site());
(setter_name, getter_name)
}
}
}
}