rust: syn: add SPDX License Identifiers

Originally, when the Rust upstream `alloc` standard library crate was
vendored in commit 057b8d2571 ("rust: adapt `alloc` crate to the
kernel"), the SPDX License Identifiers were added to every file so that
the license on those was clear.

Thus do the same for the `syn` crate.

This makes `scripts/spdxcheck.py` pass.

Reviewed-by: Gary Guo <gary@garyguo.net>
Tested-by: Gary Guo <gary@garyguo.net>
Tested-by: Jesung Yang <y.j3ms.n@gmail.com>
Link: https://patch.msgid.link/20251124151837.2184382-17-ojeda@kernel.org
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>

rust/syn/attr.rs

@@ -1,3 +1,5 @@
+// SPDX-License-Identifier: Apache-2.0 OR MIT
+
 #[cfg(feature = "parsing")]
 use crate::error::Error;
 #[cfg(feature = "parsing")]

rust/syn/bigint.rs

@@ -1,3 +1,5 @@
+// SPDX-License-Identifier: Apache-2.0 OR MIT
+
 use std::ops::{AddAssign, MulAssign};
 
 // For implementing base10_digits() accessor on LitInt.

rust/syn/buffer.rs

@@ -1,3 +1,5 @@
+// SPDX-License-Identifier: Apache-2.0 OR MIT
+
 //! A stably addressed token buffer supporting efficient traversal based on a
 //! cheaply copyable cursor.
 

rust/syn/classify.rs

@@ -1,3 +1,5 @@
+// SPDX-License-Identifier: Apache-2.0 OR MIT
+
 #[cfg(feature = "full")]
 use crate::expr::Expr;
 #[cfg(any(feature = "printing", feature = "full"))]

rust/syn/custom_keyword.rs

@@ -1,3 +1,5 @@
+// SPDX-License-Identifier: Apache-2.0 OR MIT
+
 /// Define a type that supports parsing and printing a given identifier as if it
 /// were a keyword.
 ///

rust/syn/custom_punctuation.rs

@@ -1,3 +1,5 @@
+// SPDX-License-Identifier: Apache-2.0 OR MIT
+
 /// Define a type that supports parsing and printing a multi-character symbol
 /// as if it were a punctuation token.
 ///

rust/syn/data.rs

@@ -1,3 +1,5 @@
+// SPDX-License-Identifier: Apache-2.0 OR MIT
+
 use crate::attr::Attribute;
 use crate::expr::{Expr, Index, Member};
 use crate::ident::Ident;

rust/syn/derive.rs

@@ -1,3 +1,5 @@
+// SPDX-License-Identifier: Apache-2.0 OR MIT
+
 use crate::attr::Attribute;
 use crate::data::{Fields, FieldsNamed, Variant};
 use crate::generics::Generics;

rust/syn/discouraged.rs

@@ -1,3 +1,5 @@
+// SPDX-License-Identifier: Apache-2.0 OR MIT
+
 //! Extensions to the parsing API with niche applicability.
 
 use crate::buffer::Cursor;

rust/syn/drops.rs

@@ -1,3 +1,5 @@
+// SPDX-License-Identifier: Apache-2.0 OR MIT
+
 use std::iter;
 use std::mem::ManuallyDrop;
 use std::ops::{Deref, DerefMut};

rust/syn/error.rs

@@ -1,3 +1,5 @@
+// SPDX-License-Identifier: Apache-2.0 OR MIT
+
 #[cfg(feature = "parsing")]
 use crate::buffer::Cursor;
 use crate::thread::ThreadBound;

rust/syn/export.rs

@@ -1,3 +1,5 @@
+// SPDX-License-Identifier: Apache-2.0 OR MIT
+
 #[doc(hidden)]
 pub use std::clone::Clone;
 #[doc(hidden)]

rust/syn/expr.rs

@@ -1,3 +1,5 @@
+// SPDX-License-Identifier: Apache-2.0 OR MIT
+
 use crate::attr::Attribute;
 #[cfg(all(feature = "parsing", feature = "full"))]
 use crate::error::Result;

rust/syn/ext.rs

@@ -1,3 +1,5 @@
+// SPDX-License-Identifier: Apache-2.0 OR MIT
+
 //! Extension traits to provide parsing methods on foreign types.
 
 use crate::buffer::Cursor;

rust/syn/file.rs

@@ -1,3 +1,5 @@
+// SPDX-License-Identifier: Apache-2.0 OR MIT
+
 use crate::attr::Attribute;
 use crate::item::Item;
 

rust/syn/fixup.rs

@@ -1,3 +1,5 @@
+// SPDX-License-Identifier: Apache-2.0 OR MIT
+
 use crate::classify;
 use crate::expr::Expr;
 #[cfg(feature = "full")]

rust/syn/gen/clone.rs

@@ -1,3 +1,5 @@
+// SPDX-License-Identifier: Apache-2.0 OR MIT
+
 // This file is @generated by syn-internal-codegen.
 // It is not intended for manual editing.
 

rust/syn/gen/debug.rs

@@ -1,3 +1,5 @@
+// SPDX-License-Identifier: Apache-2.0 OR MIT
+
 // This file is @generated by syn-internal-codegen.
 // It is not intended for manual editing.
 

rust/syn/gen/eq.rs

@@ -1,3 +1,5 @@
+// SPDX-License-Identifier: Apache-2.0 OR MIT
+
 // This file is @generated by syn-internal-codegen.
 // It is not intended for manual editing.
 

rust/syn/gen/fold.rs

@@ -1,3 +1,5 @@
+// SPDX-License-Identifier: Apache-2.0 OR MIT
+
 // This file is @generated by syn-internal-codegen.
 // It is not intended for manual editing.
 

rust/syn/gen/hash.rs

@@ -1,3 +1,5 @@
+// SPDX-License-Identifier: Apache-2.0 OR MIT
+
 // This file is @generated by syn-internal-codegen.
 // It is not intended for manual editing.
 

rust/syn/gen/visit.rs

@@ -1,3 +1,5 @@
+// SPDX-License-Identifier: Apache-2.0 OR MIT
+
 // This file is @generated by syn-internal-codegen.
 // It is not intended for manual editing.
 

rust/syn/gen/visit_mut.rs

@@ -1,3 +1,5 @@
+// SPDX-License-Identifier: Apache-2.0 OR MIT
+
 // This file is @generated by syn-internal-codegen.
 // It is not intended for manual editing.
 

rust/syn/generics.rs

@@ -1,3 +1,5 @@
+// SPDX-License-Identifier: Apache-2.0 OR MIT
+
 use crate::attr::Attribute;
 use crate::expr::Expr;
 use crate::ident::Ident;

rust/syn/group.rs

@@ -1,3 +1,5 @@
+// SPDX-License-Identifier: Apache-2.0 OR MIT
+
 use crate::error::Result;
 use crate::parse::ParseBuffer;
 use crate::token;

rust/syn/ident.rs

@@ -1,3 +1,5 @@
+// SPDX-License-Identifier: Apache-2.0 OR MIT
+
 #[cfg(feature = "parsing")]
 use crate::lookahead;
 

rust/syn/item.rs

@@ -1,3 +1,5 @@
+// SPDX-License-Identifier: Apache-2.0 OR MIT
+
 use crate::attr::Attribute;
 use crate::data::{Fields, FieldsNamed, Variant};
 use crate::derive::{Data, DataEnum, DataStruct, DataUnion, DeriveInput};

rust/syn/lib.rs

@@ -1,3 +1,5 @@
+// SPDX-License-Identifier: Apache-2.0 OR MIT
+
 //! [![github]](https://github.com/dtolnay/syn) [![crates-io]](https://crates.io/crates/syn) [![docs-rs]](crate)
 //!
 //! [github]: https://img.shields.io/badge/github-8da0cb?style=for-the-badge&labelColor=555555&logo=github

rust/syn/lifetime.rs

@@ -1,3 +1,5 @@
+// SPDX-License-Identifier: Apache-2.0 OR MIT
+
 #[cfg(feature = "parsing")]
 use crate::lookahead;
 use proc_macro2::{Ident, Span};

rust/syn/lit.rs

@@ -1,3 +1,5 @@
+// SPDX-License-Identifier: Apache-2.0 OR MIT
+
 #[cfg(feature = "parsing")]
 use crate::lookahead;
 #[cfg(feature = "parsing")]

rust/syn/lookahead.rs

@@ -1,3 +1,5 @@
+// SPDX-License-Identifier: Apache-2.0 OR MIT
+
 use crate::buffer::Cursor;
 use crate::error::{self, Error};
 use crate::sealed::lookahead::Sealed;

rust/syn/mac.rs

@@ -1,3 +1,5 @@
+// SPDX-License-Identifier: Apache-2.0 OR MIT
+
 #[cfg(feature = "parsing")]
 use crate::error::Result;
 #[cfg(feature = "parsing")]

rust/syn/macros.rs

@@ -1,3 +1,5 @@
+// SPDX-License-Identifier: Apache-2.0 OR MIT
+
 #[cfg_attr(
     not(any(feature = "full", feature = "derive")),
     allow(unknown_lints, unused_macro_rules)

rust/syn/meta.rs

@@ -1,3 +1,5 @@
+// SPDX-License-Identifier: Apache-2.0 OR MIT
+
 //! Facility for interpreting structured content inside of an `Attribute`.
 
 use crate::error::{Error, Result};

rust/syn/op.rs

@@ -1,3 +1,5 @@
+// SPDX-License-Identifier: Apache-2.0 OR MIT
+
 ast_enum! {
     /// A binary operator: `+`, `+=`, `&`.
     #[cfg_attr(docsrs, doc(cfg(any(feature = "full", feature = "derive"))))]

rust/syn/parse.rs

@@ -1,3 +1,5 @@
+// SPDX-License-Identifier: Apache-2.0 OR MIT
+
 //! Parsing interface for parsing a token stream into a syntax tree node.
 //!
 //! Parsing in Syn is built on parser functions that take in a [`ParseStream`]

rust/syn/parse_macro_input.rs

@@ -1,3 +1,5 @@
+// SPDX-License-Identifier: Apache-2.0 OR MIT
+
 /// Parse the input TokenStream of a macro, triggering a compile error if the
 /// tokens fail to parse.
 ///

rust/syn/parse_quote.rs

@@ -1,3 +1,5 @@
+// SPDX-License-Identifier: Apache-2.0 OR MIT
+
 /// Quasi-quotation macro that accepts input like the [`quote!`] macro but uses
 /// type inference to figure out a return type for those tokens.
 ///

rust/syn/pat.rs

@@ -1,3 +1,5 @@
+// SPDX-License-Identifier: Apache-2.0 OR MIT
+
 use crate::attr::Attribute;
 use crate::expr::Member;
 use crate::ident::Ident;

rust/syn/path.rs

@@ -1,3 +1,5 @@
+// SPDX-License-Identifier: Apache-2.0 OR MIT
+
 #[cfg(feature = "parsing")]
 use crate::error::Result;
 use crate::expr::Expr;

rust/syn/precedence.rs

@@ -1,3 +1,5 @@
+// SPDX-License-Identifier: Apache-2.0 OR MIT
+
 #[cfg(all(feature = "printing", feature = "full"))]
 use crate::attr::{AttrStyle, Attribute};
 #[cfg(feature = "printing")]

rust/syn/print.rs

@@ -1,3 +1,5 @@
+// SPDX-License-Identifier: Apache-2.0 OR MIT
+
 use proc_macro2::TokenStream;
 use quote::ToTokens;
 

rust/syn/punctuated.rs

@@ -1,3 +1,5 @@
+// SPDX-License-Identifier: Apache-2.0 OR MIT
+
 //! A punctuated sequence of syntax tree nodes separated by punctuation.
 //!
 //! Lots of things in Rust are punctuated sequences.

rust/syn/restriction.rs

@@ -1,3 +1,5 @@
+// SPDX-License-Identifier: Apache-2.0 OR MIT
+
 use crate::path::Path;
 use crate::token;
 

rust/syn/scan_expr.rs

@@ -1,3 +1,5 @@
+// SPDX-License-Identifier: Apache-2.0 OR MIT
+
 use self::{Action::*, Input::*};
 use proc_macro2::{Delimiter, Ident, Spacing, TokenTree};
 use syn::parse::{ParseStream, Result};

rust/syn/sealed.rs

@@ -1,3 +1,5 @@
+// SPDX-License-Identifier: Apache-2.0 OR MIT
+
 #[cfg(feature = "parsing")]
 pub(crate) mod lookahead {
     pub trait Sealed: Copy {}

rust/syn/span.rs

@@ -1,3 +1,5 @@
+// SPDX-License-Identifier: Apache-2.0 OR MIT
+
 use proc_macro2::extra::DelimSpan;
 use proc_macro2::{Delimiter, Group, Span, TokenStream};
 

rust/syn/spanned.rs

@@ -1,3 +1,5 @@
+// SPDX-License-Identifier: Apache-2.0 OR MIT
+
 //! A trait that can provide the `Span` of the complete contents of a syntax
 //! tree node.
 //!

rust/syn/stmt.rs

@@ -1,3 +1,5 @@
+// SPDX-License-Identifier: Apache-2.0 OR MIT
+
 use crate::attr::Attribute;
 use crate::expr::Expr;
 use crate::item::Item;

rust/syn/thread.rs

@@ -1,3 +1,5 @@
+// SPDX-License-Identifier: Apache-2.0 OR MIT
+
 use std::fmt::{self, Debug};
 use std::thread::{self, ThreadId};
 

rust/syn/token.rs

@@ -1,3 +1,5 @@
+// SPDX-License-Identifier: Apache-2.0 OR MIT
+
 //! Tokens representing Rust punctuation, keywords, and delimiters.
 //!
 //! The type names in this module can be difficult to keep straight, so we

rust/syn/tt.rs

@@ -1,3 +1,5 @@
+// SPDX-License-Identifier: Apache-2.0 OR MIT
+
 use proc_macro2::{Delimiter, TokenStream, TokenTree};
 use std::hash::{Hash, Hasher};
 

rust/syn/ty.rs

@@ -1,3 +1,5 @@
+// SPDX-License-Identifier: Apache-2.0 OR MIT
+
 use crate::attr::Attribute;
 use crate::expr::Expr;
 use crate::generics::{BoundLifetimes, TypeParamBound};

rust/syn/verbatim.rs

@@ -1,3 +1,5 @@
+// SPDX-License-Identifier: Apache-2.0 OR MIT
+
 use crate::parse::ParseStream;
 use proc_macro2::{Delimiter, TokenStream};
 use std::cmp::Ordering;

rust/syn/whitespace.rs

@@ -1,3 +1,5 @@
+// SPDX-License-Identifier: Apache-2.0 OR MIT
+
 pub(crate) fn skip(mut s: &str) -> &str {
     'skip: while !s.is_empty() {
         let byte = s.as_bytes()[0];