fix(git_branch): more robust handling of .git (#3290)

src/context.rs

@@ -274,7 +274,8 @@ impl<'a> Context<'a> {
             }?;
             Ok(Repo {
                 branch: get_current_branch(&repository),
-                root: repository.workdir().map(Path::to_path_buf),
+                workdir: repository.workdir().map(Path::to_path_buf),
+                path: Path::to_path_buf(repository.path()),
                 state: repository.state(),
                 remote: get_remote_repository_info(&repository),
             })
@@ -433,7 +434,10 @@ pub struct Repo {
 
     /// If `current_dir` is a git repository or is contained within one,
     /// this is the path to the root of that repo.
-    pub root: Option<PathBuf>,
+    pub workdir: Option<PathBuf>,
+
+    /// The path of the repository's `.git` directory.
+    pub path: PathBuf,
 
     /// State
     pub state: RepositoryState,
@@ -442,6 +446,13 @@ pub struct Repo {
     pub remote: Option<Remote>,
 }
 
+impl Repo {
+    /// Opens the associated git repository.
+    pub fn open(&self) -> Result<Repository, git2::Error> {
+        Repository::open(&self.path)
+    }
+}
+
 /// Remote repository
 pub struct Remote {
     pub branch: Option<String>,

src/modules/directory.rs

@@ -53,7 +53,7 @@ pub fn module<'a>(context: &'a Context) -> Option<Module<'a>> {
     // Otherwise use the logical path, automatically contracting
     let repo = context.get_repo().ok();
     let dir_string = if config.truncate_to_repo {
-        repo.and_then(|r| r.root.as_ref())
+        repo.and_then(|r| r.workdir.as_ref())
             .filter(|&root| root != &home_dir)
             .and_then(|root| contract_repo_path(display_dir, root))
     } else {
@@ -99,7 +99,7 @@ pub fn module<'a>(context: &'a Context) -> Option<Module<'a>> {
         String::from("")
     };
 
-    let path_vec = match &repo.and_then(|r| r.root.as_ref()) {
+    let path_vec = match &repo.and_then(|r| r.workdir.as_ref()) {
         Some(repo_root) if config.repo_root_style.is_some() => {
             let contracted_path = contract_repo_path(display_dir, repo_root)?;
             let repo_path_vec: Vec<&str> = contracted_path.split('/').collect();

src/modules/dotnet.rs

@@ -54,7 +54,7 @@ pub fn module<'a>(context: &'a Context) -> Option<Module<'a>> {
             .map(|variable| match variable {
                 "version" => {
                     let version = if enable_heuristic {
-                        let repo_root = context.get_repo().ok().and_then(|r| r.root.as_deref());
+                        let repo_root = context.get_repo().ok().and_then(|r| r.workdir.as_deref());
                         estimate_dotnet_version(
                             context,
                             &dotnet_files,

src/modules/git_branch.rs

@@ -1,7 +1,6 @@
 use unicode_segmentation::UnicodeSegmentation;
 
 use super::{Context, Module, RootModuleConfig};
-use git2::Repository;
 
 use crate::configs::git_branch::GitBranchConfig;
 use crate::formatter::StringFormatter;
@@ -27,11 +26,11 @@ pub fn module<'a>(context: &'a Context) -> Option<Module<'a>> {
 
     let repo = context.get_repo().ok()?;
 
-    if let Some(repo_root) = repo.root.as_ref() {
-        let git_repo = Repository::open(repo_root).ok()?;
-        let is_detached = git_repo.head_detached().ok()?;
-        if config.only_attached && is_detached {
-            return None;
+    if config.only_attached {
+        if let Ok(git_repo) = repo.open() {
+            if git_repo.head_detached().ok()? {
+                return None;
+            }
         }
     }
 

src/modules/git_commit.rs

@@ -1,6 +1,5 @@
 use super::{Context, Module, RootModuleConfig};
 use crate::formatter::string_formatter::StringFormatterError;
-use git2::Repository;
 use git2::Time;
 
 use crate::configs::git_commit::GitCommitConfig;
@@ -14,8 +13,7 @@ pub fn module<'a>(context: &'a Context) -> Option<Module<'a>> {
     let config: GitCommitConfig = GitCommitConfig::try_load(module.config);
 
     let repo = context.get_repo().ok()?;
-    let repo_root = repo.root.as_ref()?;
-    let git_repo = Repository::open(repo_root).ok()?;
+    let git_repo = repo.open().ok()?;
 
     let is_detached = git_repo.head_detached().ok()?;
     if config.only_detached && !is_detached {

src/modules/git_metrics.rs

@@ -21,13 +21,15 @@ pub fn module<'a>(context: &'a Context) -> Option<Module<'a>> {
     };
 
     let repo = context.get_repo().ok()?;
-    let repo_root = repo.root.as_ref()?;
+    let repo_root = repo.workdir.as_ref()?;
 
     let diff = context
         .exec_cmd(
             "git",
             &[
-                OsStr::new("-C"),
+                OsStr::new("--git-dir"),
+                repo.path.as_os_str(),
+                OsStr::new("--work-tree"),
                 repo_root.as_os_str(),
                 OsStr::new("--no-optional-locks"),
                 OsStr::new("diff"),

src/modules/git_state.rs

@@ -1,8 +1,9 @@
 use git2::RepositoryState;
-use std::path::{Path, PathBuf};
+use std::path::PathBuf;
 
 use super::{Context, Module, RootModuleConfig};
 use crate::configs::git_state::GitStateConfig;
+use crate::context::Repo;
 use crate::formatter::StringFormatter;
 
 /// Creates a module with the state of the git repository at the current directory
@@ -14,10 +15,8 @@ pub fn module<'a>(context: &'a Context) -> Option<Module<'a>> {
     let config: GitStateConfig = GitStateConfig::try_load(module.config);
 
     let repo = context.get_repo().ok()?;
-    let repo_root = repo.root.as_ref()?;
-    let repo_state = repo.state;
 
-    let state_description = get_state_description(repo_state, repo_root, &config)?;
+    let state_description = get_state_description(repo, &config)?;
 
     let parsed = StringFormatter::new(config.format).and_then(|formatter| {
         formatter
@@ -52,11 +51,10 @@ pub fn module<'a>(context: &'a Context) -> Option<Module<'a>> {
 ///
 /// During a git operation it will show: REBASING, BISECTING, MERGING, etc.
 fn get_state_description<'a>(
-    state: RepositoryState,
-    root: &'a Path,
+    repo: &'a Repo,
     config: &GitStateConfig<'a>,
 ) -> Option<StateDescription<'a>> {
-    match state {
+    match repo.state {
         RepositoryState::Clean => None,
         RepositoryState::Merge => Some(StateDescription {
             label: config.merge,
@@ -98,13 +96,13 @@ fn get_state_description<'a>(
             current: None,
             total: None,
         }),
-        RepositoryState::Rebase => Some(describe_rebase(root, config.rebase)),
-        RepositoryState::RebaseInteractive => Some(describe_rebase(root, config.rebase)),
-        RepositoryState::RebaseMerge => Some(describe_rebase(root, config.rebase)),
+        RepositoryState::Rebase => Some(describe_rebase(repo, config.rebase)),
+        RepositoryState::RebaseInteractive => Some(describe_rebase(repo, config.rebase)),
+        RepositoryState::RebaseMerge => Some(describe_rebase(repo, config.rebase)),
     }
 }
 
-fn describe_rebase<'a>(root: &'a Path, rebase_config: &'a str) -> StateDescription<'a> {
+fn describe_rebase<'a>(repo: &'a Repo, rebase_config: &'a str) -> StateDescription<'a> {
     /*
      *  Sadly, libgit2 seems to have some issues with reading the state of
      *  interactive rebases. So, instead, we'll poke a few of the .git files
@@ -113,25 +111,13 @@ fn describe_rebase<'a>(root: &'a Path, rebase_config: &'a str) -> StateDescripti
      *  The following is based heavily on: https://github.com/magicmonty/bash-git-prompt
      */
 
-    let dot_git = root.join(".git");
-    let dot_git = if let Ok(conf) = std::fs::read_to_string(&dot_git) {
-        let gitdir_re = regex::Regex::new(r"(?m)^gitdir: (.*)$").unwrap();
-        if let Some(caps) = gitdir_re.captures(&conf) {
-            root.join(caps.get(1).unwrap().as_str())
-        } else {
-            dot_git
-        }
-    } else {
-        dot_git
-    };
-
     let has_path = |relative_path: &str| {
-        let path = dot_git.join(PathBuf::from(relative_path));
+        let path = repo.path.join(PathBuf::from(relative_path));
         path.exists()
     };
 
     let file_to_usize = |relative_path: &str| {
-        let path = dot_git.join(PathBuf::from(relative_path));
+        let path = repo.path.join(PathBuf::from(relative_path));
         let contents = crate::utils::read_file(path).ok()?;
         let quantity = contents.trim().parse::<usize>().ok()?;
         Some(quantity)