chore(vendor): add anyhow crate

third_party/crates/syn-3.0.6/src/lifetime.rs

@@ -0,0 +1,193 @@
+#[cfg(feature = "parsing")]
+use crate::lookahead;
+#[cfg(feature = "parsing")]
+use crate::parse::{ParseStream, Result};
+use core::cmp::Ordering;
+use core::fmt::{self, Display};
+use core::hash::{Hash, Hasher};
+use proc_macro2::{Ident, Span};
+
+/// A Rust lifetime: `'a`.
+///
+/// Lifetime names must conform to the following rules:
+///
+/// - Must start with an apostrophe.
+/// - Must not consist of just an apostrophe: `'`.
+/// - Character after the apostrophe must be `_` or a Unicode code point with
+///   the XID_Start property.
+/// - All following characters must be Unicode code points with the XID_Continue
+///   property.
+pub struct Lifetime {
+    pub apostrophe: Span,
+    pub ident: Ident,
+}
+
+impl Lifetime {
+    /// # Panics
+    ///
+    /// Panics if the lifetime does not conform to the bulleted rules above.
+    ///
+    /// # Invocation
+    ///
+    /// ```
+    /// # use proc_macro2::Span;
+    /// # use syn::Lifetime;
+    /// #
+    /// # fn f() -> Lifetime {
+    /// Lifetime::new("'a", Span::call_site())
+    /// # }
+    /// ```
+    pub fn new(symbol: &str, span: Span) -> Self {
+        let ident = match symbol.strip_prefix('\'') {
+            Some(ident) => ident,
+            None => panic!(
+                "lifetime name must start with apostrophe as in \"'a\", got {:?}",
+                symbol,
+            ),
+        };
+
+        let unraw = ident.strip_prefix("r#");
+        let validate = unraw.unwrap_or(ident);
+        if validate.is_empty() {
+            panic!("lifetime name must not be empty");
+        }
+        if !crate::ident::xid_ok(validate) {
+            panic!("{:?} is not a valid lifetime name", symbol);
+        }
+
+        Lifetime {
+            apostrophe: span,
+            ident: match unraw {
+                Some(unraw) => Ident::new_raw(unraw, span),
+                None => Ident::new(ident, span),
+            },
+        }
+    }
+
+    pub fn span(&self) -> Span {
+        self.apostrophe
+            .join(self.ident.span())
+            .unwrap_or(self.apostrophe)
+    }
+
+    pub fn set_span(&mut self, span: Span) {
+        self.apostrophe = span;
+        self.ident.set_span(span);
+    }
+
+    #[cfg(feature = "parsing")]
+    #[cfg_attr(docsrs, doc(cfg(feature = "parsing")))]
+    pub fn parse_any(input: ParseStream) -> Result<Self> {
+        input.step(|cursor| match cursor.lifetime() {
+            Some((lifetime, rest)) => Ok((lifetime, rest)),
+            None => Err(cursor.error("expected lifetime")),
+        })
+    }
+}
+
+impl Display for Lifetime {
+    fn fmt(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
+        "'".fmt(formatter)?;
+        self.ident.fmt(formatter)
+    }
+}
+
+impl Clone for Lifetime {
+    fn clone(&self) -> Self {
+        Lifetime {
+            apostrophe: self.apostrophe,
+            ident: self.ident.clone(),
+        }
+    }
+}
+
+impl PartialEq for Lifetime {
+    fn eq(&self, other: &Lifetime) -> bool {
+        self.ident.eq(&other.ident)
+    }
+}
+
+impl Eq for Lifetime {}
+
+impl PartialOrd for Lifetime {
+    fn partial_cmp(&self, other: &Lifetime) -> Option<Ordering> {
+        Some(self.cmp(other))
+    }
+}
+
+impl Ord for Lifetime {
+    fn cmp(&self, other: &Lifetime) -> Ordering {
+        self.ident.cmp(&other.ident)
+    }
+}
+
+impl Hash for Lifetime {
+    fn hash<H: Hasher>(&self, h: &mut H) {
+        self.ident.hash(h);
+    }
+}
+
+#[cfg(feature = "parsing")]
+pub_if_not_doc! {
+    #[doc(hidden)]
+    #[allow(non_snake_case)]
+    pub fn Lifetime(marker: lookahead::TokenMarker) -> Lifetime {
+        match marker {}
+    }
+}
+
+#[cfg(feature = "parsing")]
+pub(crate) mod parsing {
+    use crate::error::Result;
+    use crate::ident;
+    use crate::lifetime::Lifetime;
+    use crate::parse::{Parse, ParseStream};
+    use alloc::string::ToString;
+
+    #[cfg_attr(docsrs, doc(cfg(feature = "parsing")))]
+    impl Parse for Lifetime {
+        fn parse(input: ParseStream) -> Result<Self> {
+            input.step(|cursor| {
+                if let Some((lifetime, rest)) = cursor.lifetime() {
+                    let repr = lifetime.ident.to_string();
+                    if ident::parsing::accept_as_ident(&repr) || repr == "static" || repr == "_" {
+                        Ok((lifetime, rest))
+                    } else {
+                        Err(cursor
+                            .error(format_args!("unexpected keyword lifetime \"{}\"", lifetime)))
+                    }
+                } else {
+                    Err(cursor.error("expected lifetime"))
+                }
+            })
+        }
+    }
+
+    impl Lifetime {
+        #[cfg(any(feature = "full", feature = "derive"))]
+        pub(crate) fn parse_optional_any(input: ParseStream) -> Option<Self> {
+            input
+                .step(|cursor| match cursor.lifetime() {
+                    Some((lifetime, rest)) => Ok((Some(lifetime), rest)),
+                    None => Ok((None, *cursor)),
+                })
+                .unwrap()
+        }
+    }
+}
+
+#[cfg(feature = "printing")]
+mod printing {
+    use crate::ext::PunctExt as _;
+    use crate::lifetime::Lifetime;
+    use proc_macro2::{Punct, Spacing, TokenStream};
+    use quote::{ToTokens, TokenStreamExt as _};
+
+    #[cfg_attr(docsrs, doc(cfg(feature = "printing")))]
+    impl ToTokens for Lifetime {
+        fn to_tokens(&self, tokens: &mut TokenStream) {
+            tokens.append(Punct::new_spanned('\'', Spacing::Joint, self.apostrophe));
+            self.ident.to_tokens(tokens);
+        }
+    }
+}