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// Rust language amplification derive library providing multiple generic trait // implementations, type wrappers, derive macros and other language enhancements // // Written in 2019-2021 by // Dr. Maxim Orlovsky <orlovsky@pandoracore.com> // // To the extent possible under law, the author(s) have dedicated all // copyright and related and neighboring rights to this software to // the public domain worldwide. This software is distributed without // any warranty. // // You should have received a copy of the MIT License // along with this software. // If not, see <https://opensource.org/licenses/MIT>. use std::fmt::{Debug, Formatter, self}; use std::collections::{HashMap, HashSet}; use syn::{ Type, Path, Attribute, Meta, MetaList, MetaNameValue, NestedMeta, Lit, LitInt, LitStr, LitByteStr, LitFloat, LitChar, LitBool, }; use crate::{Error, ArgValue, ArgReq, AttrReq}; /// Internal structure representation of a proc macro attribute collected /// instances having some specific name (accessible via [`Attr::name()`]). #[derive(Clone, Debug)] pub enum Attr { /// Attribute of `#[attr]` or `#[attr = value]` form, which, aside from the /// case where `value` is a string literal, may have only a single /// occurrence (string literals are concatenated into a single value like /// rust compiler does for `#[doc = "..."]` attributes). Singular(SingularAttr), /// Parametrized attribute in form of `#[attr(...)]`, where parameters are /// gathered from all attribute occurrences. Parametrized(ParametrizedAttr), } /// Structure describing a procedural macro attribute with an optional value. /// The means that if one has something like `#[name1]`, `#[name2 = "value"]`, /// `#[name3 = ::std::path::PathBuf)]` than `name1`, `name2 = "value"`, and /// `name3 = ::std::path::PathBuf` are three different attributes which can be /// parsed and represented by the [`SingularAttr`] structure. /// /// NB: For `#[attr(arg1, arg2 = value)]` style of proc macros use /// [`ParametrizedAttr`] structure. If you need to support both use [`Attr`] /// enum. /// /// Internally the structure is composed of the `name` and `value` fields, /// where name is always a [`Ident`] (corresponding `name1`, `name2`, `name3` /// from the sample above) and `value` is an optional literal [`Lit`], with /// corresponding cases of `None`, /// `Some(`[`AttrArgValue::Lit`]`(`[`Lit::Str`]`(`[`LitStr`]`)))`, and /// `Some(`[`AttrArgValue::Type`]`(`[`Type::Path`]`(`[`Path`]`)))`. #[derive(Clone, Debug)] pub struct SingularAttr { /// Optional attribute argument path part; for instance in /// `#[my(name = value)]` or in `#[name = value]` this is a `name` part pub name: String, /// Attribute argument value part; for instance in `#[name = value]` this is /// the `value` part pub value: ArgValue, } /// Representation for all allowed forms of `#[attr(...)]` attribute. /// If attribute has a multiple occurrences they are all assembled into a single /// list. Repeated named arguments are not allowed and result in errors. /// /// For situations like in `#[attr("string literal")]`, [`ParametrizedAttr`] /// will have a `name` field set to `attr`, `literal` field set to /// `Lit::LitStr(LitStr("string literal"))`, `args` will be an empty `HashSet` /// and `paths` will be represented by an empty vector. #[derive(Clone)] pub struct ParametrizedAttr { /// Attribute name - `attr` part of `#[attr(...)]` pub name: String, /// All attribute arguments that have form of `#[attr(ident = "literal")]` /// or `#[attr(ident = TypeName)]` mapped to their name identifiers. pub args: HashMap<String, ArgValue>, /// All attribute arguments that are paths or identifiers without any /// specific value, like `#[attr(std::io::Error, crate, super::SomeType)]`. /// /// NB: All named arguments without the value assigned are getting into this /// field by default, even if they do not represent any known rust path or /// type name, like `#[attr(some_id, other)]`. However, with /// [`ParametrizedAttr::check`] and [`ParametrizedAttr::checked`] those /// values matching ones specified in [`AttrReq::args`] with values set to /// [`ValueOccurrences::Default`] are moved into [`ParametrizedAttr::args`]. pub paths: Vec<Path>, /// Unnamed string literal found within attribute arguments. /// /// If multiple string literals are present they are concatenated into a /// single value, like it is done by the rust compiler for /// `#[doc = "..."]` attributes pub string: Option<LitStr>, /// Unnamed byte string literal found within attribute arguments. /// /// If multiple byte string literals are present they are concatenated into /// a single value, like it is done by the rust compiler for /// `#[doc = "..."]` attributes pub bytes: Option<LitByteStr>, /// Unnamed char literals found within attribute arguments pub chars: Vec<LitChar>, /// Unnamed integer literals found within attribute arguments pub integers: Vec<LitInt>, /// Unnamed float literals found within attribute arguments pub floats: Vec<LitFloat>, /// Unnamed bool literal found within attribute arguments. /// /// If multiple bool literals are present this will generate an error. pub bool: Option<LitBool>, } impl Attr { /// Constructs [`Attr`] from a vector of all syn-parsed attributes, /// selecting attributes matching the provided name. pub fn with(name: impl ToString + AsRef<str>, attrs: &Vec<Attribute>) -> Result<Self, Error> { SingularAttr::with(name.to_string(), attrs) .map(|singular| Attr::Singular(singular)) .or_else(|_| ParametrizedAttr::with(name, attrs).map(|param| Attr::Parametrized(param))) } /// Constructor parsing [`Attribute`] value and returning either /// [`SingularAttr`] or [`ParametrizedAttr`] packed in form of [`Attr`] /// enum. /// /// If the attribute does not match either of forms, a [`Error`] is /// returned. Currently, only single type of error may occur in practice: /// - [`Error::ArgNameMustBeIdent`], which happens if the attribute name is /// not an [`Ident`] but is a complex path value pub fn from_attribute(attr: &Attribute) -> Result<Self, Error> { SingularAttr::from_attribute(attr) .map(|singular| Attr::Singular(singular)) .or_else(|_| { ParametrizedAttr::from_attribute(attr).map(|param| Attr::Parametrized(param)) }) } /// Returns inner value \in form of [`SingularAttr`] for [`Attr::Singular`] /// variant, or fails with [`Error::SingularAttrRequired`] otherwise #[inline] pub fn try_singular(self) -> Result<SingularAttr, Error> { match self { Attr::Singular(attr) => Ok(attr), Attr::Parametrized(attr) => Err(Error::SingularAttrRequired(attr.name)), } } /// Returns inner value \in form of [`ParametrizedAttr`] for /// [`Attr::Parametrized`] variant, or fails with /// [`Error::ParametrizedAttrRequired`] otherwise #[inline] pub fn try_parametrized(self) -> Result<ParametrizedAttr, Error> { match self { Attr::Singular(attr) => Err(Error::ParametrizedAttrRequired(attr.name)), Attr::Parametrized(attr) => Ok(attr), } } /// Returns string reference to the argument name #[inline] pub fn name(&self) -> &str { match self { Attr::Singular(attr) => &attr.name, Attr::Parametrized(attr) => &attr.name, } } /// Returns [`ArgValue`] for the [`Attr::Singular`] variant or fails with /// [`Error::ParametrizedAttrHasNoValue`] #[inline] pub fn arg_value(&self) -> Result<ArgValue, Error> { match self { Attr::Singular(attr) => Ok(attr.value.clone()), Attr::Parametrized(attr) => Err(Error::ParametrizedAttrHasNoValue(attr.name.clone())), } } /// Returns literal value for the [`Attr::Singular`] variant or fails with /// [`Error::ParametrizedAttrHasNoValue`]. See [`ArgValue::literal_value`] /// for more details. #[inline] pub fn literal_value(&self) -> Result<Lit, Error> { self.arg_value()?.literal_value() } /// Returns type value for the [`Attr::Singular`] variant or fails with /// [`Error::ParametrizedAttrHasNoValue`]. See [`ArgValue::literal_value`] /// for more details. #[inline] pub fn type_value(&self) -> Result<Type, Error> { self.arg_value()?.type_value() } } impl SingularAttr { /// Constructs named [`SingularAttr`] without value #[inline] pub fn new(name: impl ToString) -> Self { Self { name: name.to_string(), value: ArgValue::None, } } /// Constructs [`SingularAttr`] from a vector of all syn-parsed attributes, /// selecting single attribute matching the provided name. If there are /// multiple instances of the same attribute, fails with /// [`Error::SingularAttrRequired`] pub fn with(name: impl ToString, attrs: &Vec<Attribute>) -> Result<Self, Error> { let name = name.to_string(); let mut filtered_attrs = attrs.iter().filter(|attr| attr.path.is_ident(&name)); let res = if let Some(attr) = filtered_attrs.next() { SingularAttr::from_attribute(attr) } else { return Err(Error::SingularAttrRequired(name)); }; if filtered_attrs.count() > 0 { return Err(Error::SingularAttrRequired(name)); } res } /// Constructs named [`SingularAttr`] setting its value to the provided /// literal #[inline] pub fn with_literal(name: impl ToString, lit: Lit) -> Self { Self { name: name.to_string(), value: ArgValue::Literal(lit), } } /// Constructs named [`SingularAttr`] setting its value to the provided /// rust type value #[inline] pub fn with_type(name: impl ToString, ty: Type) -> Self { Self { name: name.to_string(), value: ArgValue::Type(ty), } } /// Constructs [`SingularAttr`] from a given [`syn::Attribute`] by parsing /// its data. Accepts only attributes having form `#[attr(name = value)]` /// and errors for other attribute types with [`Error::ArgNameMustBeIdent`] /// and [`Error::SingularAttrRequired`] pub fn from_attribute(attr: &Attribute) -> Result<Self, Error> { let ident = attr .path .get_ident() .ok_or(Error::ArgNameMustBeIdent)? .to_string(); match attr.parse_meta()? { // `#[attr::path]` - unreachable: filtered in the code above Meta::Path(_) => unreachable!(), // `#[ident = lit]` Meta::NameValue(MetaNameValue { lit, .. }) => { Ok(SingularAttr::with_literal(ident, lit)) } // `#[ident(...)]` Meta::List(_) => Err(Error::SingularAttrRequired(ident)), } } /// Returns literal value, if any, or fails with /// [`Error::ArgValueRequired`]. See [`ArgValue::literal_value`] for the /// details. #[inline] pub fn literal_value(&self) -> Result<Lit, Error> { self.value.literal_value() } /// Returns type value, if any, or fails with [`Error::ArgValueRequired`]. /// See [`ArgValue::literal_value`] for the details. #[inline] pub fn type_value(&self) -> Result<Type, Error> { self.value.type_value() } /// Merges data from the `other` into the self. /// /// # Errors /// /// - Fails with [`Error::NamesDontMatch`] if the names of the self and the /// `other` do not match /// - Fails with [`Error::MultipleSingularValues`] if both self and the /// `other` has a named argument with the same name but different values. pub fn merge(&mut self, other: Self) -> Result<(), Error> { if self.name != other.name { return Err(Error::NamesDontMatch(self.name.clone(), other.name.clone())); } match (&self.value, &other.value) { (_, ArgValue::None) => {} (ArgValue::None, _) => self.value = other.value, (_, _) => return Err(Error::MultipleSingularValues(self.name.clone())), } Ok(()) } /// Does merging as in [`SingularAttr::merge`], but unlike it consumes /// the self and returns a merged structure in case of the successful /// operation. Useful in operation chains. #[inline] pub fn merged(mut self, other: Self) -> Result<Self, Error> { self.merge(other)?; Ok(self) } /// Enriches current attribute data by adding information from the provided /// [`syn::Attribute`]. /// /// # Errors /// /// - Fails with [`Error::NamesDontMatch`] if the names of the self and the /// provided attribute do not match /// - Fails with [`Error::MultipleSingularValues`] if both self and the /// provided attribute has a named argument with the same name but /// different values. #[inline] pub fn enrich(&mut self, attr: &Attribute) -> Result<(), Error> { self.merge(SingularAttr::from_attribute(attr)?) } /// Performs enrich operation as in [`SingularAttr::enrich`], but unlike it /// consumes the self and returns an enriched structure in case of the /// successful operation. Useful in operation chains. #[inline] pub fn enriched(mut self, attr: &Attribute) -> Result<Self, Error> { self.enrich(attr)?; Ok(self) } /// Checks that the structure meets provided value requirements (see /// [`ValueReq`]), generating [`Error`] if the requirements are not met. pub fn check(&mut self, req: ArgReq) -> Result<(), Error> { req.check(&mut self.value, &self.name, &self.name)?; Ok(()) } /// Performs check as in [`SingularAttr::check`], but unlike it consumes the /// self and returns a itself in case of the successful operation. /// Useful in operation chains. #[inline] pub fn checked(mut self, req: ArgReq) -> Result<Self, Error> { self.check(req)?; Ok(self) } } impl ParametrizedAttr { /// Constructs named [`SingularAttr`] with empty internal data #[inline] pub fn new(name: impl ToString) -> Self { Self { name: name.to_string(), args: Default::default(), paths: vec![], string: None, bytes: None, chars: vec![], integers: vec![], floats: vec![], bool: None, } } /// Constructs [`ParametrizedAttr`] from a vector of all syn-parsed /// attributes, selecting attributes matching the provided name. pub fn with(name: impl ToString + AsRef<str>, attrs: &Vec<Attribute>) -> Result<Self, Error> { let mut me = ParametrizedAttr::new(name.to_string()); for attr in attrs.iter().filter(|attr| attr.path.is_ident(&name)) { match attr.parse_meta()? { // `#[ident(...)]` Meta::List(MetaList { nested, .. }) => { for meta in nested { me.fuse(meta)?; } } _ => return Err(Error::ParametrizedAttrRequired(name.to_string())), } } Ok(me) } /// Constructs [`ParametrizedAttr`] from a given [`syn::Attribute`] pub fn from_attribute(attr: &Attribute) -> Result<Self, Error> { let name = attr .path .get_ident() .ok_or(Error::ArgNameMustBeIdent)? .to_string(); match attr.parse_meta()? { // `#[ident(...)]` Meta::List(MetaList { nested, .. }) => nested .into_iter() .fold(Ok(ParametrizedAttr::new(name)), |res, nested| { res.and_then(|attr| attr.fused(nested)) }), _ => Err(Error::ParametrizedAttrRequired(name)), } } /// Returns literal value for a given argument with name `name`, if it is /// defined, or fails with [`Error::ArgValueRequired`]. See /// [`ArgValue::literal_value`] for the details. pub fn arg_literal_value(&self, name: &str) -> Result<Lit, Error> { self.args .get(name) .ok_or(Error::ArgRequired { attr: self.name.clone(), arg: name.to_owned(), })? .literal_value() } /// Checks if the attribute has a verbatim argument matching the provided /// `verbatim` string. /// /// Verbatim arguments are arguments in form of `#[attr(verbatim1, /// verbatim2]`, i.e. path arguments containing single path segment and no /// value or nested arguments. pub fn has_verbatim(&self, verbatim: &str) -> bool { self.paths .iter() .find(|path| path.is_ident(verbatim)) .is_some() } /// Returns set of verbatim attribute arguments. /// /// Verbatim arguments are arguments in form of `#[attr(verbatim1, /// verbatim2]`, i.e. path arguments containing single path segment and no /// value or nested arguments. pub fn verbatim(&self) -> HashSet<String> { self.paths .iter() .filter_map(Path::get_ident) .map(|ident| ident.to_string()) .collect() } /// Merges data from the `other` into the self. /// /// # Errors /// /// - Fails with [`Error::NamesDontMatch`] if the names of the self and the /// `other` do not match /// - Fails with [`Error::MultipleLiteralValues`] if both self and the /// `other` has a literals which values are not equal. pub fn merge(&mut self, other: Self) -> Result<(), Error> { if self.name != other.name { return Err(Error::NamesDontMatch(self.name.clone(), other.name.clone())); } self.args.extend(other.args); self.paths.extend(other.paths); self.integers.extend(other.integers); self.floats.extend(other.floats); self.chars.extend(other.chars); match (&mut self.string, &other.string) { (_, None) => {} (None, Some(_)) => self.string = other.string.clone(), (Some(str1), Some(str2)) => { *str1 = LitStr::new(&format!("{} {}", str1.value(), str2.value()), str1.span()); } } match (&mut self.bytes, &other.bytes) { (_, None) => {} (None, Some(_)) => self.bytes = other.bytes.clone(), (Some(bytes1), Some(bytes2)) => { let mut joined = bytes1.value(); joined.extend(bytes2.value()); *bytes1 = LitByteStr::new(&joined, bytes1.span()); } } match (&mut self.bool, &other.bool) { (_, None) => {} (None, Some(_)) => self.bool = other.bool.clone(), (Some(_), Some(_)) => return Err(Error::MultipleLiteralValues(self.name.clone())), } Ok(()) } /// Does merging as in [`ParametrizedAttr::merge`], but unlike it consumes /// the self and returns a merged structure in case of the successful /// operation. Useful in operation chains. #[inline] pub fn merged(mut self, other: Self) -> Result<Self, Error> { self.merge(other)?; Ok(self) } /// Enriches current attribute data by adding information from the provided /// [`syn::Attribute`]. /// /// # Errors /// /// - Fails with [`Error::NamesDontMatch`] if the names of the self and the /// provided attribute do not match /// - Fails with [`Error::MultipleLiteralValues`] if both self and the /// provided attribute has a literals which values are not equal. #[inline] pub fn enrich(&mut self, attr: &Attribute) -> Result<(), Error> { self.merge(ParametrizedAttr::from_attribute(attr)?) } /// Performs enrich operation as in [`ParametrizedAttr::enrich`], but unlike /// it consumes the self and returns an enriched structure in case of /// the successful operation. Useful in operation chains. #[inline] pub fn enriched(mut self, attr: &Attribute) -> Result<Self, Error> { self.enrich(attr)?; Ok(self) } /// Fuses data from a nested attribute arguments (see [`syn::NestedMeta`]) /// into the attribute parameters. /// /// The operation is similar to the [`ParametrizedAttr::enrich`] with the /// only difference that enrichment operation takes the whole attribute, and /// fusion takes a nested meta data. #[inline] pub fn fuse(&mut self, nested: NestedMeta) -> Result<(), Error> { match nested { // `#[ident("literal", ...)]` NestedMeta::Lit(Lit::Str(s)) => { let span = s.span(); match self.string { None => self.string = Some(s), Some(ref mut str1) => { let mut joined = str1.value(); joined.push_str(&s.value()); *str1 = LitStr::new(&joined, span); } } } // `#[ident(b"literal", ...)]` NestedMeta::Lit(Lit::ByteStr(s)) => { let span = s.span(); match self.bytes { None => self.bytes = Some(s), Some(ref mut str1) => { let mut joined = str1.value(); joined.extend(&s.value()); *str1 = LitByteStr::new(&joined, span); } } } // `#[ident(3, ...)]` NestedMeta::Lit(Lit::Int(lit)) => self.integers.push(lit), // `#[ident(2.3, ...)]` NestedMeta::Lit(Lit::Float(lit)) => self.floats.push(lit), // `#[ident('a', ...)]` NestedMeta::Lit(Lit::Char(lit)) => self.chars.push(lit), // `#[ident(true, ...)]` NestedMeta::Lit(Lit::Bool(_)) if self.bool.is_some() => { return Err(Error::MultipleLiteralValues(self.name.clone())) } NestedMeta::Lit(Lit::Bool(lit)) if self.bool.is_none() => self.bool = Some(lit.clone()), // `#[ident(true, ...)]` NestedMeta::Lit(_) => return Err(Error::UnsupportedLiteral(self.name.clone())), // `#[ident(arg::path)]` NestedMeta::Meta(Meta::Path(path)) => self.paths.push(path), // `#[ident(name = value, ...)]` NestedMeta::Meta(Meta::NameValue(MetaNameValue { path, lit, .. })) => { let id = path .clone() .get_ident() .ok_or(Error::ArgNameMustBeIdent)? .to_string(); if self .args .insert(id.clone(), ArgValue::Literal(lit)) .is_some() { return Err(Error::ArgNameMustBeUnique { attr: self.name.clone(), arg: id, }); } } // `#[ident(arg(...), ...)]` NestedMeta::Meta(Meta::List(_)) => { return Err(Error::NestedListsNotSupported(self.name.clone())) } } Ok(()) } /// Performs enrich operation as in [`ParametrizedAttr::fuse`], but unlike /// it consumes the self and returns an enriched structure in case of /// the successful operation. Useful in operation chains. #[inline] pub fn fused(mut self, nested: NestedMeta) -> Result<Self, Error> { self.fuse(nested)?; Ok(self) } /// Checks that the structure meets provided value requirements (see /// [`AttrReq`]), generating [`Error`] if the requirements are not met. /// /// The procedure modifies the [`ParametrizedAttr`] data in the following /// ways: /// 1. First, it fills in [`ParametrizedAttr::paths`], /// [`ParametrizedAttr::integers`] and [`ParametrizedAttr::literal`] with /// default values from [`AttrReq::paths`], [`AttrReq::integers`] and /// [`AttrReq::literal`] (correspondingly). /// 2. [`ParametrizedAttr::paths`] values matching ones specified in /// [`AttrReq::args`] with values set to [`ValueOccurrences::Default`] /// are moved into [`ParametrizedAttr::args`] field. pub fn check(&mut self, req: AttrReq) -> Result<(), Error> { for (name, req) in &req.arg_req { if let Some(pos) = self.paths.iter().position(|path| path.is_ident(name)) { self.paths.remove(pos); self.args.entry(name.clone()).or_insert(req.default_value()); } if !self.args.contains_key(name) && req.is_required() { return Err(Error::ArgRequired { attr: self.name.clone(), arg: name.clone(), }); } } for (name, value) in &mut self.args { let req = if let Some(req) = req.arg_req.get(name) { req } else { return Err(Error::AttributeUnknownArgument { attr: self.name.clone(), arg: name.clone(), }); }; req.check(value, &self.name, name)?; } req.path_req.check(&mut self.paths, &self.name, "path")?; req.integer_req .check(&mut self.integers, &self.name, "integer literal")?; req.float_req .check(&mut self.floats, &self.name, "float literal")?; req.char_req .check(&mut self.chars, &self.name, "char literal")?; req.string_req .check(&mut self.string, &self.name, "string literal")?; req.bool_req .check(&mut self.bool, &self.name, "bool literal")?; req.bytes_req .check(&mut self.bytes, &self.name, "byte string literal")?; Ok(()) } /// Performs check as in [`ParametrizedAttr::check`], but unlike it /// consumes the self and returns a itself in case of the successful /// operation. Useful in operation chains. #[inline] pub fn checked(mut self, req: AttrReq) -> Result<Self, Error> { self.check(req)?; Ok(self) } } // This trait should not be implemented for the types outside of this crate #[doc(hidden)] pub trait ExtractAttr { #[doc(hidden)] fn singular_attr( self, name: impl ToString + AsRef<str>, req: ArgReq, ) -> Result<Option<SingularAttr>, Error>; #[doc(hidden)] fn parametrized_attr( self, name: impl ToString + AsRef<str>, req: AttrReq, ) -> Result<Option<ParametrizedAttr>, Error>; } impl<'a, T> ExtractAttr for T where T: IntoIterator<Item = &'a Attribute>, { /// Returns a [`SingularAttr`] which structure must fulfill the provided /// requirements - or fails with a [`Error`] otherwise. For more information /// check [`ValueReq`] requirements info. fn singular_attr( self, name: impl ToString + AsRef<str>, req: ArgReq, ) -> Result<Option<SingularAttr>, Error> { let mut attr = SingularAttr::new(name.to_string()); let filtered = self .into_iter() .filter(|attr| attr.path.is_ident(&name)) .collect::<Vec<_>>(); if filtered.is_empty() { return Ok(None); } for entries in filtered { attr.enrich(entries)?; } Some(attr.checked(req)).transpose() } /// Returns a [`ParametrizedAttr`] which structure must fulfill the provided /// requirements - or fails with a [`Error`] otherwise. For more information /// check [`AttrReq`] requirements info. fn parametrized_attr( self, name: impl ToString + AsRef<str>, req: AttrReq, ) -> Result<Option<ParametrizedAttr>, Error> { let mut attr = ParametrizedAttr::new(name.to_string()); let filtered = self .into_iter() .filter(|attr| attr.path.is_ident(&name)) .collect::<Vec<_>>(); if filtered.is_empty() { return Ok(None); } for entries in filtered { attr.enrich(entries)?; } Some(attr.checked(req)).transpose() } } impl Debug for ParametrizedAttr { fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result { f.write_str("ParametrizedAttr({")?; if f.alternate() { f.write_str("\n\t")?; } write!(f, "name: {:?},", self.name)?; if f.alternate() { f.write_str("\n\t")?; } f.write_str("args: {")?; if !self.args.is_empty() { if f.alternate() { f.write_str("\n")?; } for (name, val) in &self.args { if f.alternate() { f.write_str("\t\t")?; } write!(f, "{} => {:?},", name, val)?; if f.alternate() { f.write_str("\n")?; } } if f.alternate() { f.write_str("\t")?; } } f.write_str("},")?; if f.alternate() { f.write_str("\n\t")?; } f.write_str("paths: [")?; if !self.paths.is_empty() { if f.alternate() { f.write_str("\n")?; } for path in &self.paths { if f.alternate() { f.write_str("\t\t")?; } write!(f, "{},", quote! { #path })?; if f.alternate() { f.write_str("\n")?; } } if f.alternate() { f.write_str("\t")?; } } f.write_str("],")?; if f.alternate() { f.write_str("\n\t")?; } write!( f, "bool: {:?},", self.bool .as_ref() .map(|b| format!("Some({:?})", b.value)) .unwrap_or("None".to_owned()) )?; if f.alternate() { f.write_str("\n\t")?; } write!( f, "string: {:?},", self.string .as_ref() .map(|s| format!("Some({:?})", s.value())) .unwrap_or("None".to_owned()) )?; if f.alternate() { f.write_str("\n\t")?; } write!( f, "bytes: {:?}", self.bytes .as_ref() .map(|s| format!("Some({:?})", s.value())) .unwrap_or("None".to_owned()) )?; if f.alternate() { f.write_str("\n\t")?; } f.write_str("chars: [")?; if !self.chars.is_empty() { if f.alternate() { f.write_str("\n")?; } for c in &self.chars { if f.alternate() { f.write_str("\t\t")?; } write!(f, "{},", quote! { #c })?; if f.alternate() { f.write_str("\n")?; } } if f.alternate() { f.write_str("\t")?; } } f.write_str("],")?; if f.alternate() { f.write_str("\n\t")?; } f.write_str("integers: [")?; if !self.integers.is_empty() { if f.alternate() { f.write_str("\n")?; } for c in &self.integers { if f.alternate() { f.write_str("\t\t")?; } write!(f, "{},", quote! { #c })?; if f.alternate() { f.write_str("\n")?; } } if f.alternate() { f.write_str("\t")?; } } f.write_str("],")?; if f.alternate() { f.write_str("\n\t")?; } f.write_str("floats: [")?; if !self.floats.is_empty() { if f.alternate() { f.write_str("\n")?; } for c in &self.floats { if f.alternate() { f.write_str("\t\t")?; } write!(f, "{},", quote! { #c })?; if f.alternate() { f.write_str("\n")?; } } if f.alternate() { f.write_str("\t")?; } } f.write_str("],")?; if f.alternate() { f.write_str("\n")?; } f.write_str("})")?; if f.alternate() { f.write_str("\n")?; } Ok(()) } }