build: fix --branch flag

The `--branch` flag is optional and takes a string argument.

The `--branch` flag does not make sense for `luarocks make` because
it does not fetch sources, it builds/installs based on whatever is
in the current directory.

This also adds tests that verify the behavior, but these don't
run in Travis CI because of issues running a Git daemon there.
They were verified locally.

1 files changed, 1 insertions, 0 deletions

diff --git a/spec/util/git_repo.lua b/spec/util/git_repo.lua
index 6cccfcc4..b3ddd9ef 100644
--- a/spec/util/git_repo.lua
+++ b/spec/util/git_repo.lua
@@ -82,6 +82,7 @@ function git_repo.start()
             test_env.execute("git add " .. name)
          end
          assert(test_env.execute("git commit -a -m 'initial commit'"))
+         assert(test_env.execute("git branch test-branch"))
          print("git daemon --reuseaddr --pid-file="..pidfile.." --base-path="..basedir.." --export-all "..repodir.." &")
          assert(test_env.execute("git daemon --reuseaddr --pid-file="..pidfile.." --base-path="..basedir.." --export-all "..repodir.." &"))
          assert(test_env.execute("sleep 0.1; netstat -ln | grep '0.0.0.0:9418 .* LISTEN'"))