syn_solidity/variable/
mod.rs

1use crate::{Expr, SolIdent, Spanned, Storage, Type, VariableAttributes};
2use proc_macro2::Span;
3use std::fmt::{self, Write};
4use syn::{
5    ext::IdentExt,
6    parse::{Parse, ParseStream},
7    Attribute, Ident, Result, Token,
8};
9
10mod list;
11pub use list::{FieldList, ParameterList, Parameters};
12
13/// A variable declaration: `string memory hello`.
14#[derive(Clone, Debug, PartialEq, Eq, Hash)]
15pub struct VariableDeclaration {
16    /// The attributes of the variable.
17    pub attrs: Vec<Attribute>,
18    /// The type of the variable.
19    pub ty: Type,
20    /// The storage location of the variable, if any.
21    pub storage: Option<Storage>,
22    /// The name of the variable. This is always Some if parsed as part of
23    /// [`Parameters`] or a [`Stmt`][crate::Stmt].
24    pub name: Option<SolIdent>,
25}
26
27impl fmt::Display for VariableDeclaration {
28    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
29        self.ty.fmt(f)?;
30        if let Some(storage) = &self.storage {
31            f.write_char(' ')?;
32            storage.fmt(f)?;
33        }
34        if let Some(name) = &self.name {
35            f.write_char(' ')?;
36            name.fmt(f)?;
37        }
38        Ok(())
39    }
40}
41
42impl Parse for VariableDeclaration {
43    fn parse(input: ParseStream<'_>) -> Result<Self> {
44        Self::_parse(input, false)
45    }
46}
47
48impl Spanned for VariableDeclaration {
49    fn span(&self) -> Span {
50        let span = self.ty.span();
51        match (&self.storage, &self.name) {
52            (Some(storage), None) => span.join(storage.span()),
53            (_, Some(name)) => span.join(name.span()),
54            (None, None) => Some(span),
55        }
56        .unwrap_or(span)
57    }
58
59    fn set_span(&mut self, span: Span) {
60        self.ty.set_span(span);
61        if let Some(storage) = &mut self.storage {
62            storage.set_span(span);
63        }
64        if let Some(name) = &mut self.name {
65            name.set_span(span);
66        }
67    }
68}
69
70impl VariableDeclaration {
71    pub const fn new(ty: Type) -> Self {
72        Self::new_with(ty, None, None)
73    }
74
75    pub const fn new_with(ty: Type, storage: Option<Storage>, name: Option<SolIdent>) -> Self {
76        Self { attrs: Vec::new(), ty, storage, name }
77    }
78
79    /// Formats `self` as an EIP-712 field: `<ty> <name>`
80    pub fn fmt_eip712(&self, f: &mut impl Write) -> fmt::Result {
81        write!(f, "{}", self.ty)?;
82        if let Some(name) = &self.name {
83            write!(f, " {name}")?;
84        }
85        Ok(())
86    }
87
88    pub fn parse_with_name(input: ParseStream<'_>) -> Result<Self> {
89        Self::_parse(input, true)
90    }
91
92    fn _parse(input: ParseStream<'_>, require_name: bool) -> Result<Self> {
93        Ok(Self {
94            attrs: input.call(Attribute::parse_outer)?,
95            ty: input.parse()?,
96            storage: input.call(Storage::parse_opt)?,
97            name: if require_name || input.peek(Ident::peek_any) {
98                Some(input.parse()?)
99            } else {
100                None
101            },
102        })
103    }
104}
105
106#[derive(Clone)]
107pub struct VariableDefinition {
108    pub attrs: Vec<Attribute>,
109    pub ty: Type,
110    pub attributes: VariableAttributes,
111    pub name: SolIdent,
112    pub initializer: Option<(Token![=], Expr)>,
113    pub semi_token: Token![;],
114}
115
116impl fmt::Display for VariableDefinition {
117    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
118        write!(f, "{} {} {}", self.ty, self.attributes, self.name)?;
119        if let Some((_, _expr)) = &self.initializer {
120            // TODO: fmt::Display for Expr
121            write!(f, " = <expr>")?;
122        }
123        f.write_str(";")
124    }
125}
126
127impl fmt::Debug for VariableDefinition {
128    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
129        f.debug_struct("VariableDefinition")
130            .field("ty", &self.ty)
131            .field("attributes", &self.attributes)
132            .field("name", &self.name)
133            .field("initializer", &self.initializer)
134            .finish()
135    }
136}
137
138impl Parse for VariableDefinition {
139    fn parse(input: ParseStream<'_>) -> Result<Self> {
140        Ok(Self {
141            attrs: Attribute::parse_outer(input)?,
142            ty: input.parse()?,
143            attributes: input.parse()?,
144            name: input.parse()?,
145            initializer: if input.peek(Token![=]) {
146                Some((input.parse()?, input.parse()?))
147            } else {
148                None
149            },
150            semi_token: input.parse()?,
151        })
152    }
153}
154
155impl Spanned for VariableDefinition {
156    fn span(&self) -> Span {
157        let span = self.ty.span();
158        span.join(self.semi_token.span).unwrap_or(span)
159    }
160
161    fn set_span(&mut self, span: Span) {
162        self.ty.set_span(span);
163        self.semi_token.span = span;
164    }
165}
166
167impl VariableDefinition {
168    pub fn as_declaration(&self) -> VariableDeclaration {
169        VariableDeclaration {
170            attrs: Vec::new(),
171            ty: self.ty.clone(),
172            storage: None,
173            name: Some(self.name.clone()),
174        }
175    }
176}