support portage build-id extension

src/atom/parsers.rs

@@ -94,16 +94,19 @@ impl<'a> Parseable<'a, &'a str> for Version {
 
     fn parser() -> Self::Parser {
         let rev = VersionNumber::parser().preceded_by(tag("-r"));
+        let build_id = VersionNumber::parser().preceded_by(tag("-"));
 
         VersionNumbers::parser()
             .and(r#if(|c: &char| c.is_ascii_alphabetic() && c.is_ascii_lowercase()).opt())
             .and(VersionSuffixes::parser().preceded_by(tag("_")).opt())
             .and(rev.opt())
-            .map(|(((numbers, letter), suffixes), rev)| Version {
+            .and(build_id.opt())
+            .map(|((((numbers, letter), suffixes), rev), build_id)| Version {
                 numbers,
                 letter,
                 suffixes: suffixes.unwrap_or(VersionSuffixes(Vec::new())),
                 rev,
+                build_id,
             })
     }
 }