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#![deny(
anonymous_parameters,
clippy::all,
const_err,
illegal_floating_point_literal_pattern,
late_bound_lifetime_arguments,
path_statements,
patterns_in_fns_without_body,
rust_2018_idioms,
trivial_casts,
trivial_numeric_casts,
unreachable_pub,
unsafe_code,
unused_extern_crates
)]
#![warn(
clippy::dbg_macro,
clippy::decimal_literal_representation,
clippy::get_unwrap,
clippy::nursery,
clippy::print_stdout,
clippy::todo,
clippy::unimplemented,
clippy::unnested_or_patterns,
clippy::unwrap_used,
clippy::use_debug,
single_use_lifetimes,
unused_qualifications,
variant_size_differences
)]
#![allow(
clippy::missing_const_for_fn, // useless in proc macro
clippy::redundant_pub_crate, // suggests bad style
clippy::option_if_let_else, // suggests terrible code
)]
#[macro_use]
mod quote;
mod date;
mod datetime;
mod error;
#[cfg(any(feature = "formatting", feature = "parsing"))]
mod format_description;
mod helpers;
mod offset;
#[cfg(all(feature = "serde", any(feature = "formatting", feature = "parsing")))]
mod serde_format_description;
mod time;
mod to_tokens;
use proc_macro::TokenStream;
#[cfg(all(feature = "serde", any(feature = "formatting", feature = "parsing")))]
use proc_macro::TokenTree;
use self::error::Error;
macro_rules! impl_macros {
($($name:ident)*) => {$(
#[proc_macro]
pub fn $name(input: TokenStream) -> TokenStream {
use crate::to_tokens::ToTokenTree;
let mut iter = input.into_iter().peekable();
match $name::parse(&mut iter) {
Ok(value) => match iter.peek() {
Some(tree) => Error::UnexpectedToken { tree: tree.clone() }.to_compile_error(),
None => TokenStream::from(value.into_token_tree()),
},
Err(err) => err.to_compile_error(),
}
}
)*};
}
impl_macros![date datetime offset time];
#[cfg(any(feature = "formatting", feature = "parsing"))]
#[proc_macro]
pub fn format_description(input: TokenStream) -> TokenStream {
(|| {
let (span, string) = helpers::get_string_literal(input)?;
let items = format_description::parse(&string, span)?;
Ok(quote! {{
const DESCRIPTION: &[::time::format_description::FormatItem<'_>] = &[#S(
items
.into_iter()
.map(|item| quote! { #S(item), })
.collect::<TokenStream>()
)];
DESCRIPTION
}})
})()
.unwrap_or_else(|err: Error| err.to_compile_error())
}
#[cfg(all(feature = "serde", any(feature = "formatting", feature = "parsing")))]
#[proc_macro]
pub fn serde_format_description(input: TokenStream) -> TokenStream {
(|| {
let mut tokens = input.into_iter().peekable();
// First, an identifier (the desired module name)
let mod_name = match tokens.next() {
Some(TokenTree::Ident(ident)) => Ok(ident),
Some(tree) => Err(Error::UnexpectedToken { tree }),
None => Err(Error::UnexpectedEndOfInput),
}?;
// Followed by a comma
helpers::consume_punct(',', &mut tokens)?;
// Then, the type to create serde serializers for (e.g., `OffsetDateTime`).
let formattable = match tokens.next() {
Some(tree @ TokenTree::Ident(_)) => Ok(tree),
Some(tree) => Err(Error::UnexpectedToken { tree }),
None => Err(Error::UnexpectedEndOfInput),
}?;
// Another comma
helpers::consume_punct(',', &mut tokens)?;
// We now have two options. The user can either provide a format description as a string or
// they can provide a path to a format description. If the latter, all remaining tokens are
// assumed to be part of the path.
let (format, raw_format_string) = match tokens.peek() {
// string literal
Some(TokenTree::Literal(_)) => {
let (span, format_string) = helpers::get_string_literal(tokens.collect())?;
let items = format_description::parse(&format_string, span)?;
let items: TokenStream =
items.into_iter().map(|item| quote! { #S(item), }).collect();
let items = quote! { &[#S(items)] };
(
items,
Some(String::from_utf8_lossy(&format_string).into_owned()),
)
}
// path
Some(_) => (
quote! {{
// We can't just do `super::path` because the path could be an absolute path. In
// that case, we'd be generating `super::::path`, which is invalid. Even if we
// took that into account, it's not possible to know if it's an external crate,
// which would just require emitting `path` directly. By taking this approach,
// we can leave it to the compiler to do the actual resolution.
mod __path_hack {
pub(super) use super::super::*;
pub(super) use #S(tokens.collect::<TokenStream>()) as FORMAT;
}
__path_hack::FORMAT
}},
None,
),
None => return Err(Error::UnexpectedEndOfInput),
};
Ok(serde_format_description::build(
mod_name,
formattable,
format,
raw_format_string,
))
})()
.unwrap_or_else(|err: Error| err.to_compile_error_standalone())
}
|
