Squashed 'third_party/autocxx/' content from commit 629e8fa53
git-subtree-dir: third_party/autocxx
git-subtree-split: 629e8fa531a633164c0b52e2a3cab536d4cd0849
Signed-off-by: Brian Silverman <bsilver16384@gmail.com>
Change-Id: I62a03b0049f49adf029e0204639cdb5468dde1a1
diff --git a/parser/src/path.rs b/parser/src/path.rs
new file mode 100644
index 0000000..415b2ef
--- /dev/null
+++ b/parser/src/path.rs
@@ -0,0 +1,67 @@
+// Copyright 2021 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// https://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or https://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+use crate::ParseResult;
+use proc_macro2::Ident;
+use quote::{quote, ToTokens, TokenStreamExt};
+use syn::parse::{Parse, ParseStream};
+
+/// A little like [`syn::Path`] but simpler - contains only identifiers,
+/// no path arguments. Guaranteed to always have at least one identifier.
+#[derive(Debug, Clone, Hash, PartialEq, Eq)]
+pub struct RustPath(Vec<Ident>);
+
+impl RustPath {
+ pub fn new_from_ident(id: Ident) -> Self {
+ Self(vec![id])
+ }
+
+ #[must_use]
+ pub fn append(&self, id: Ident) -> Self {
+ Self(self.0.iter().cloned().chain(std::iter::once(id)).collect())
+ }
+
+ pub fn get_final_ident(&self) -> &Ident {
+ self.0.last().unwrap()
+ }
+
+ pub fn len(&self) -> usize {
+ self.0.len()
+ }
+
+ pub fn is_empty(&self) -> bool {
+ self.0.is_empty()
+ }
+}
+
+impl ToTokens for RustPath {
+ fn to_tokens(&self, tokens: &mut proc_macro2::TokenStream) {
+ let mut it = self.0.iter();
+ let mut id = it.next();
+ while id.is_some() {
+ id.unwrap().to_tokens(tokens);
+ let next = it.next();
+ if next.is_some() {
+ tokens.append_all(quote! { :: });
+ }
+ id = next;
+ }
+ }
+}
+
+impl Parse for RustPath {
+ fn parse(input: ParseStream) -> ParseResult<Self> {
+ let id: Ident = input.parse()?;
+ let mut p = RustPath::new_from_ident(id);
+ while input.parse::<Option<syn::token::Colon2>>()?.is_some() {
+ let id: Ident = input.parse()?;
+ p = p.append(id);
+ }
+ Ok(p)
+ }
+}