Silence git checkout warnings (#128)

This silences the `git checkout` warnings. I wasn't sure if you wanted
to remove output from the other git commands, too?

Fixes: #126

crates/ubrn_cli/src/repo.rs

@@ -79,21 +79,33 @@ impl GitRepoArgs {
             run_cmd(&mut cmd)?;
         }
 
-        // git ls-remote origin $branch
+        // git remote set-branches origin '*' to start tracking all branches and
+        // enable checking out branch names
+        let mut cmd = Command::new("git");
+        cmd.current_dir(self.directory(project_root)?)
+            .arg("remote")
+            .arg("set-branches")
+            .arg("origin")
+            .arg("*");
+        run_cmd(&mut cmd)?;
+
+        // git ls-remote --tags origin $branch
         let output = Command::new("git")
             .current_dir(self.directory(project_root)?)
             .arg("ls-remote")
+            .arg("--tags")
             .arg("origin")
             .arg(&self.branch)
             .output()?;
         let output = String::from_utf8(output.stdout)?;
 
-        // Find $branch in the output and resolve the SHA or fall back to $branch
-        let branch_ref = format!("refs/heads/{}", &self.branch);
+        // Find $branch in the output and resolve the SHA or fall back to $branch. We
+        // deliberately don't resolve branch names to their SHAs because checking out
+        // with the SHA would cause a detached HEAD state.
         let tag_ref = format!("refs/tags/{}", &self.branch);
         let sha = output
             .lines()
-            .find(|line| line.ends_with(&branch_ref) || line.ends_with(&tag_ref))
+            .find(|line| line.ends_with(&tag_ref))
             .map(|line| {
                 line.split_whitespace()
                     .next()

scripts/run-checkout-tests.sh

@@ -9,50 +9,72 @@ function clean_up {
 }
 
 function announce {
-  echo "[TEST] $1"
+  echo -e "\033[0;36m[TEST] $1\033[0m"
 }
 
 rc=0
 
 function assert_eq {
   if [[ $1 == $2 ]]; then
-    echo "✅ OK"
+    echo "✅ OK: '$1' == '$2'"
   else
-    echo "❌ FAILURE: '$1' != '$2'"
+    echo "❌ FAILURE: '$1' == '$2'"
+    rc=1
+  fi
+}
+
+function assert_contains {
+  if [[ $1 == *$2* ]]; then
+    echo "✅ OK: contains '$2'"
+  else
+    echo "❌ FAILURE: contains '$2'"
+    rc=1
+  fi
+}
+
+function assert_does_not_contain {
+  if [[ $1 != *$2* ]]; then
+    echo "✅ OK: does not contain '$2'"
+  else
+    echo "❌ FAILURE: does not contain '$2'"
     rc=1
   fi
 }
 
 clean_up
 
 announce "checkout with default"
-"$ubrn" checkout https://github.com/actions/checkout
+stderr=$("$ubrn" checkout https://github.com/actions/checkout 2> >(tee /dev/stderr))
 pushd rust_modules/checkout
 assert_eq $(git ls-remote --heads origin | grep refs/heads/main | cut -f1) $(git rev-parse HEAD)
+assert_does_not_contain "$stderr" "detached HEAD"
 popd
 
 clean_up
 
 announce "checkout with branch"
-"$ubrn" checkout https://github.com/actions/checkout --branch releases/v1
+stderr=$("$ubrn" checkout https://github.com/actions/checkout --branch releases/v1 2> >(tee /dev/stderr))
 pushd rust_modules/checkout
 assert_eq $(git ls-remote --heads origin | grep refs/heads/releases/v1 | cut -f1) $(git rev-parse HEAD)
+assert_does_not_contain "$stderr" "detached HEAD"
 popd
 
 clean_up
 
 announce "checkout with tag"
-"$ubrn" checkout https://github.com/actions/checkout --branch v4.0.0
+stderr=$("$ubrn" checkout https://github.com/actions/checkout --branch v4.0.0 2> >(tee /dev/stderr))
 pushd rust_modules/checkout
 assert_eq $(git ls-remote --tags origin | grep refs/tags/v4.0.0 | cut -f1) $(git rev-parse HEAD)
+assert_contains "$stderr" "detached HEAD"
 popd
 
 clean_up
 
 announce "checkout with sha"
-"$ubrn" checkout https://github.com/actions/checkout --branch c533a0a4cfc4962971818edcfac47a2899e69799
+stderr=$("$ubrn" checkout https://github.com/actions/checkout --branch c533a0a4cfc4962971818edcfac47a2899e69799 2> >(tee /dev/stderr))
 pushd rust_modules/checkout
 assert_eq c533a0a4cfc4962971818edcfac47a2899e69799 $(git rev-parse HEAD)
+assert_contains "$stderr" "detached HEAD"
 popd
 
 clean_up