feat: add branch - config and workflow

src/git.rs

@@ -0,0 +1,114 @@
+use std::path::Path;
+use std::process::Command;
+
+use anyhow::{Context, Result, bail};
+
+pub fn current_branch(workdir: &Path) -> Result<Option<String>> {
+    let out = match Command::new("git")
+        .current_dir(workdir)
+        .args(["rev-parse", "--abbrev-ref", "HEAD"])
+        .output()
+    {
+        Ok(out) => out,
+        Err(err) if err.kind() == std::io::ErrorKind::NotFound => {
+            bail!("`git` not found in PATH — install git to use the 'branch' check")
+        }
+        Err(err) => return Err(err).context("failed to spawn `git`"),
+    };
+
+    if !out.status.success() {
+        let stderr = String::from_utf8_lossy(&out.stderr);
+        let fail = stderr.trim();
+        if fail.contains("not a git repository")
+            || fail.contains("not inside any git repository")
+            || fail.contains("does not appear to be a git repository")
+        {
+            return Ok(None);
+        }
+        bail!("`git rev-parse` failed: {}", fail);
+    }
+
+    let name = String::from_utf8(out.stdout)
+        .context("git returned non-UTF-8 output")?
+        .trim()
+        .to_string();
+    if name.is_empty() {
+        return Ok(None);
+    }
+    Ok(Some(name))
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use std::fs;
+    use std::path::PathBuf;
+
+    fn tmpdir(tag: &str) -> PathBuf {
+        let dir =
+            std::env::temp_dir().join(format!("xboct-deploy-git-{}-{tag}", std::process::id()));
+        let _ = fs::remove_dir_all(&dir);
+        fs::create_dir_all(&dir).unwrap();
+        dir
+    }
+
+    fn git(dir: &Path, args: &[&str]) {
+        let status = Command::new("git")
+            .current_dir(dir)
+            .args(args)
+            .status()
+            .unwrap();
+        assert!(status.success(), "git {args:?} failed in {}", dir.display());
+    }
+
+    fn git_repo(tag: &str) -> PathBuf {
+        let dir = tmpdir(tag);
+        git(&dir, &["init", "-b", "test"]);
+        fs::write(dir.join("f.txt"), "hi").unwrap();
+        git(&dir, &["add", "."]);
+        git(
+            &dir,
+            &[
+                "-c",
+                "user.email=t@t",
+                "-c",
+                "user.name=t",
+                "commit",
+                "-m",
+                "init",
+            ],
+        );
+        dir
+    }
+
+    #[test]
+    fn returns_branch_in_repo() {
+        let dir = git_repo("branch");
+        assert_eq!(current_branch(&dir).unwrap().as_deref(), Some("test"));
+        let _ = fs::remove_dir_all(dir);
+    }
+
+    #[test]
+    fn returns_head_when_detached() {
+        let dir = git_repo("detached");
+        git(&dir, &["switch", "--detach"]);
+        assert_eq!(current_branch(&dir).unwrap().as_deref(), Some("HEAD"));
+        let _ = fs::remove_dir_all(dir);
+    }
+
+    #[test]
+    fn returns_none_outside_repo() {
+        let dir = tmpdir("norepo");
+        assert_eq!(current_branch(&dir).unwrap(), None);
+        let _ = fs::remove_dir_all(dir);
+    }
+
+    #[test]
+    fn works_from_subdirectory() {
+        let dir = git_repo("subdir");
+        let sub = dir.join("inner");
+        fs::create_dir_all(&sub).unwrap();
+        assert_eq!(current_branch(&sub).unwrap().as_deref(), Some("test"));
+        let _ = fs::remove_dir_all(dir);
+    }
+}