fetchGit: Support Git trees without any commits

Fixes

  $ nix build
  fatal: bad revision 'HEAD'
  error: program 'git' failed with exit code 128

on a new flake. It is now detected as a dirty tree with revCount = 0.
This commit is contained in:
Eelco Dolstra 2019-10-07 15:44:32 +02:00
parent ce2c755d2a
commit a15f9b37eb
No known key found for this signature in database
GPG key ID: 8170B4726D7198DE

View file

@ -33,13 +33,19 @@ GitInfo exportGit(ref<Store> store, std::string uri,
// or revision is given, then allow the use of an unclean working
// tree.
if (!ref && !rev && isLocal) {
bool clean = true;
bool clean = false;
/* Check whether this repo has any commits. There are
probably better ways to do this. */
bool haveCommits = !readDirectory(uri + "/.git/refs/heads").empty();
try {
if (haveCommits) {
runProgram("git", true, { "-C", uri, "diff-index", "--quiet", "HEAD", "--" });
clean = true;
}
} catch (ExecError & e) {
if (!WIFEXITED(e.status) || WEXITSTATUS(e.status) != 1) throw;
clean = false;
}
if (!clean) {
@ -75,10 +81,10 @@ GitInfo exportGit(ref<Store> store, std::string uri,
};
gitInfo.storePath = store->addToStore("source", uri, true, htSHA256, filter);
gitInfo.revCount = std::stoull(runProgram("git", true, { "-C", uri, "rev-list", "--count", "HEAD" }));
gitInfo.revCount = haveCommits ? std::stoull(runProgram("git", true, { "-C", uri, "rev-list", "--count", "HEAD" })) : 0;
// FIXME: maybe we should use the timestamp of the last
// modified dirty file?
gitInfo.lastModified = std::stoull(runProgram("git", true, { "-C", uri, "show", "-s", "--format=%ct", "HEAD" }));
gitInfo.lastModified = haveCommits ? std::stoull(runProgram("git", true, { "-C", uri, "show", "-s", "--format=%ct", "HEAD" })) : 0;
return gitInfo;
}