diff options
Diffstat (limited to 'vendor/syn/tests/test_parse_buffer.rs')
-rw-r--r-- | vendor/syn/tests/test_parse_buffer.rs | 92 |
1 files changed, 92 insertions, 0 deletions
diff --git a/vendor/syn/tests/test_parse_buffer.rs b/vendor/syn/tests/test_parse_buffer.rs new file mode 100644 index 0000000..2205b50 --- /dev/null +++ b/vendor/syn/tests/test_parse_buffer.rs @@ -0,0 +1,92 @@ +#![allow(clippy::non_ascii_literal)] + +use proc_macro2::{Delimiter, Group, Punct, Spacing, TokenStream, TokenTree}; +use syn::parse::discouraged::Speculative as _; +use syn::parse::{Parse, ParseStream, Parser, Result}; +use syn::{parenthesized, Token}; + +#[test] +#[should_panic(expected = "Fork was not derived from the advancing parse stream")] +fn smuggled_speculative_cursor_between_sources() { + struct BreakRules; + impl Parse for BreakRules { + fn parse(input1: ParseStream) -> Result<Self> { + let nested = |input2: ParseStream| { + input1.advance_to(input2); + Ok(Self) + }; + nested.parse_str("") + } + } + + syn::parse_str::<BreakRules>("").unwrap(); +} + +#[test] +#[should_panic(expected = "Fork was not derived from the advancing parse stream")] +fn smuggled_speculative_cursor_between_brackets() { + struct BreakRules; + impl Parse for BreakRules { + fn parse(input: ParseStream) -> Result<Self> { + let a; + let b; + parenthesized!(a in input); + parenthesized!(b in input); + a.advance_to(&b); + Ok(Self) + } + } + + syn::parse_str::<BreakRules>("()()").unwrap(); +} + +#[test] +#[should_panic(expected = "Fork was not derived from the advancing parse stream")] +fn smuggled_speculative_cursor_into_brackets() { + struct BreakRules; + impl Parse for BreakRules { + fn parse(input: ParseStream) -> Result<Self> { + let a; + parenthesized!(a in input); + input.advance_to(&a); + Ok(Self) + } + } + + syn::parse_str::<BreakRules>("()").unwrap(); +} + +#[test] +fn trailing_empty_none_group() { + fn parse(input: ParseStream) -> Result<()> { + input.parse::<Token![+]>()?; + + let content; + parenthesized!(content in input); + content.parse::<Token![+]>()?; + + Ok(()) + } + + // `+ ( + <Ø Ø> ) <Ø <Ø Ø> Ø>` + let tokens = TokenStream::from_iter(vec![ + TokenTree::Punct(Punct::new('+', Spacing::Alone)), + TokenTree::Group(Group::new( + Delimiter::Parenthesis, + TokenStream::from_iter(vec![ + TokenTree::Punct(Punct::new('+', Spacing::Alone)), + TokenTree::Group(Group::new(Delimiter::None, TokenStream::new())), + ]), + )), + TokenTree::Group(Group::new(Delimiter::None, TokenStream::new())), + TokenTree::Group(Group::new( + Delimiter::None, + TokenStream::from_iter(vec![TokenTree::Group(Group::new( + Delimiter::None, + TokenStream::new(), + ))]), + )), + ]); + + parse.parse2(tokens).unwrap(); +} |