Fix parsing of legacy git.git commit

gitoxide-core/src/index/information.rs

@@ -33,9 +33,6 @@ mod serde_only {
                     }
                 }
             }
-
-            #[derive(serde::Serialize, serde::Deserialize)]
-            pub struct NodeId {}
         }
     }
 

gix-object/src/commit/decode.rs

@@ -44,14 +44,14 @@ pub fn commit<'a, E: ParserError<&'a [u8]> + AddContext<&'a [u8], StrContext>>(
             .context(StrContext::Expected("author <signature>".into())),
         (|i: &mut _| parse::header_field(i, b"committer", parse::signature))
             .context(StrContext::Expected("committer <signature>".into())),
-        opt(|i: &mut _| parse::header_field(i, b"encoding", take_till(1.., NL)))
+        opt(|i: &mut _| parse::header_field(i, b"encoding", take_till(0.., NL)))
             .context(StrContext::Expected("encoding <encoding>".into())),
         repeat(
             0..,
             alt((
                 parse::any_header_field_multi_line.map(|(k, o)| (k.as_bstr(), Cow::Owned(o))),
                 |i: &mut _| {
-                    parse::any_header_field(i, take_till(1.., NL))
+                    parse::any_header_field(i, take_till(0.., NL))
                         .map(|(k, o)| (k.as_bstr(), Cow::Borrowed(o.as_bstr())))
                 },
             )),

gix-object/src/commit/ref_iter.rs

@@ -214,7 +214,7 @@ impl<'a> CommitRefIter<'a> {
                 }
             }
             Encoding => {
-                let encoding = opt(|i: &mut _| parse::header_field(i, b"encoding", take_till(1.., NL)))
+                let encoding = opt(|i: &mut _| parse::header_field(i, b"encoding", take_till(0.., NL)))
                     .context(StrContext::Expected("encoding <encoding>".into()))
                     .parse_next(input)?;
                 *state = State::ExtraHeaders;
@@ -227,7 +227,7 @@ impl<'a> CommitRefIter<'a> {
                 let extra_header = opt(alt((
                     |i: &mut _| parse::any_header_field_multi_line(i).map(|(k, o)| (k.as_bstr(), Cow::Owned(o))),
                     |i: &mut _| {
-                        parse::any_header_field(i, take_till(1.., NL))
+                        parse::any_header_field(i, take_till(0.., NL))
                             .map(|(k, o)| (k.as_bstr(), Cow::Borrowed(o.as_bstr())))
                     },
                 )))

gix-object/src/encode.rs

@@ -38,7 +38,9 @@ pub(crate) fn header_field_multi_line(name: &[u8], value: &[u8], out: &mut dyn i
     let mut lines = value.as_bstr().lines_with_terminator();
     out.write_all(name)?;
     out.write_all(SPACE)?;
-    out.write_all(lines.next().ok_or(Error::EmptyValue)?)?;
+    if let Some(line) = lines.next() {
+        out.write_all(line)?;
+    }
     for line in lines {
         out.write_all(SPACE)?;
         out.write_all(line)?;

gix-object/src/parse.rs

@@ -18,7 +18,7 @@ pub(crate) fn any_header_field_multi_line<'a, E: ParserError<&'a [u8]> + AddCont
     (
         terminated(take_till(1.., SPACE_OR_NL), SPACE),
         (
-            take_till(1.., NL),
+            take_till(0.., NL),
             NL,
             repeat(1.., terminated((SPACE, take_until(0.., NL)), NL)).map(|()| ()),
         )

gix-object/tests/fixtures/commit/bogus-gpgsig-lines-in-git.git.txt

@@ -0,0 +1,31 @@
+tree db079155794727ac821adfba2eb68b330cc0c120
+parent 33a11a20eb7610771268e34211509cbbdee76b1e
+author Junio C Hamano <[email protected]> 1319256362 -0700
+committer Junio C Hamano <[email protected]> 1319259176 -0700
+gpgsig -----BEGIN PGP SIGNATURE-----
+gpgsig Version: GnuPG v1.4.10 (GNU/Linux)
+gpgsig 
+gpgsig iQIcBAABAgAGBQJOokwoAAoJELC16IaWr+bL0WoP/2QKYkWpEyXF608m2L/cB9Qx
+gpgsig /N0oBjyL1guIjPX9B3Wxq80dnLLEPnpnO39aiQIXFoJS0L6KEurqK6uDPHy3/ULa
+gpgsig QsAug2HeCLsDnIFbzFSpSIMv/bP/72FDb/idMBT99xTcQj5UJEUgj7AAtx0vnKvQ
+gpgsig pQIXtPu5GBUdhl3SiGgiJFRyp4r5EgV5I40GBwx/ty9cPEIN7ukJ3CR9+KC8eIGx
+gpgsig Az7qngi3dhTn7g+3Z8XX5OYFDMSt9xn1gxqWXOMNlG0mxCvpFe59kwciugp26KVp
+gpgsig n+yJ0UOdoxyZX8pdqXQjvklmoo7e55aaxtbHe7KSD56ebL7h7vHhkGWORU1dOp+h
+gpgsig Iv5dQItkKSR8afB7FmRjo8+B/2g0wZDKRTGhzm7d1gooO5gpXvuvm4GRl5Io+IEj
+gpgsig c7Li3EYmXADWUZWJtbDKDgKGKIOmWv72Qrz52iaESrhZ909HiXfn/jhHBuDRmLtQ
+gpgsig /4v3T4O25uhdZ4p/PjHQn/ZroCmDyMwmnrtw/tt5fSNrl4qGcYg8Jj/1ynfF1AtS
+gpgsig dM2LR65sOwXzSsqAbQjyRFYMLSWhHd/h8BcpZHDXmNBkZJVPm4zvD3ZVaAo6rtZD
+gpgsig WJ9YXWXtPhuf09OgYBzcBlamTrk9ByH+NCIdrFkqfhNF1YI5dArSZytIXJhpPI1e
+gpgsig TrmQAZf0BiI5J6PYN0AI
+gpgsig =Qg/+
+gpgsig -----END PGP SIGNATURE-----
+
+pretty: %G[?GS] placeholders
+
+Add new placeholders related to the GPG signature on signed commits.
+
+ - %GG to show the raw verification message from GPG;
+ - %G? to show either "G" for Good, "B" for Bad;
+ - %GS to show the name of the signer.
+
+Signed-off-by: Junio C Hamano <[email protected]>

gix-object/tests/object/commit/from_bytes.rs

@@ -1,10 +1,10 @@
 use gix_actor::SignatureRef;
-use gix_object::{bstr::ByteSlice, commit::message::body::TrailerRef, CommitRef};
+use gix_object::{bstr::ByteSlice, commit::message::body::TrailerRef, CommitRef, WriteTo};
 use smallvec::SmallVec;
 
 use crate::{
     commit::{LONG_MESSAGE, MERGE_TAG, SIGNATURE},
-    fixture_name, linus_signature, signature,
+    fixture_name, hex_to_id, linus_signature, signature,
 };
 
 #[test]
@@ -342,3 +342,27 @@ fn newline_right_after_signature_multiline_header() -> crate::Result {
     assert!(commit.message.starts_with(b"Rollup"));
     Ok(())
 }
+
+#[test]
+fn bogus_multi_gpgsig_header() -> crate::Result {
+    let fixture = fixture_name("commit", "bogus-gpgsig-lines-in-git.git.txt");
+    let commit = CommitRef::from_bytes(&fixture)?;
+    let pgp_sig = b"-----BEGIN PGP SIGNATURE-----".as_bstr();
+    assert_eq!(commit.extra_headers().pgp_signature(), Some(pgp_sig));
+    assert_eq!(
+        commit.extra_headers().find_all("gpgsig").count(),
+        17,
+        "Each signature header line is prefixed with `gpgsig` here, so we parse it as extra header"
+    );
+    assert!(commit.message.starts_with(b"pretty: %G[?GS] placeholders"));
+
+    let mut buf = Vec::<u8>::new();
+    commit.write_to(&mut buf)?;
+    let actual = gix_object::compute_hash(gix_hash::Kind::Sha1, gix_object::Kind::Commit, &buf)?;
+    assert_eq!(
+        actual,
+        hex_to_id("5f549aa2f78314ac37bbd436c8f80aea4c752e07"),
+        "round-tripping works despite the strangeness"
+    );
+    Ok(())
+}