use anyhow::{bail, Context, Result}; use arc_swap::ArcSwap; use std::path::Path; use std::sync::Arc; use gix::objs::tree::EntryMode; use gix::sec::trust::DefaultForLevel; use gix::{Commit, ObjectId, Repository, ThreadSafeRepository}; use crate::DiffProvider; #[cfg(test)] mod test; pub struct Git; impl Git { fn open_repo(path: &Path, ceiling_dir: Option<&Path>) -> Result { // custom open options let mut git_open_opts_map = gix::sec::trust::Mapping::::default(); // On windows various configuration options are bundled as part of the installations // This path depends on the install location of git and therefore requires some overhead to lookup // This is basically only used on windows and has some overhead hence it's disabled on other platforms. // `gitoxide` doesn't use this as default let config = gix::permissions::Config { system: true, git: true, user: true, env: true, includes: true, git_binary: cfg!(windows), }; // change options for config permissions without touching anything else git_open_opts_map.reduced = git_open_opts_map.reduced.permissions(gix::Permissions { config, ..gix::Permissions::default_for_level(gix::sec::Trust::Reduced) }); git_open_opts_map.full = git_open_opts_map.full.permissions(gix::Permissions { config, ..gix::Permissions::default_for_level(gix::sec::Trust::Full) }); let mut open_options = gix::discover::upwards::Options::default(); if let Some(ceiling_dir) = ceiling_dir { open_options.ceiling_dirs = vec![ceiling_dir.to_owned()]; } let res = ThreadSafeRepository::discover_with_environment_overrides_opts( path, open_options, git_open_opts_map, )?; Ok(res) } } impl DiffProvider for Git { fn get_diff_base(&self, file: &Path) -> Result> { debug_assert!(!file.exists() || file.is_file()); debug_assert!(file.is_absolute()); // TODO cache repository lookup let repo_dir = file.parent().context("file has no parent directory")?; let repo = Git::open_repo(repo_dir, None) .context("failed to open git repo")? .to_thread_local(); let head = repo.head_commit()?; let file_oid = find_file_in_commit(&repo, &head, file)?; let file_object = repo.find_object(file_oid)?; let mut data = file_object.detach().data; // convert LF to CRLF if configured to avoid showing every line as changed if repo .config_snapshot() .boolean("core.autocrlf") .unwrap_or(false) { let mut normalized_file = Vec::with_capacity(data.len()); let mut at_cr = false; for &byte in &data { if byte == b'\n' { // if this is a LF instead of a CRLF (last byte was not a CR) // insert a new CR to generate a CRLF if !at_cr { normalized_file.push(b'\r'); } } at_cr = byte == b'\r'; normalized_file.push(byte) } data = normalized_file } Ok(data) } fn get_current_head_name(&self, file: &Path) -> Result>>> { debug_assert!(!file.exists() || file.is_file()); debug_assert!(file.is_absolute()); let repo_dir = file.parent().context("file has no parent directory")?; let repo = Git::open_repo(repo_dir, None) .context("failed to open git repo")? .to_thread_local(); let head_ref = repo.head_ref()?; let head_commit = repo.head_commit()?; let name = match head_ref { Some(reference) => reference.name().shorten().to_string(), None => head_commit.id.to_hex_with_len(8).to_string(), }; Ok(Arc::new(ArcSwap::from_pointee(name.into_boxed_str()))) } } /// Finds the object that contains the contents of a file at a specific commit. fn find_file_in_commit(repo: &Repository, commit: &Commit, file: &Path) -> Result { let repo_dir = repo.work_dir().context("repo has no worktree")?; let rel_path = file.strip_prefix(repo_dir)?; let tree = commit.tree()?; let tree_entry = tree .lookup_entry_by_path(rel_path)? .context("file is untracked")?; match tree_entry.mode() { // not a file, everything is new, do not show diff mode @ (EntryMode::Tree | EntryMode::Commit | EntryMode::Link) => { bail!("entry at {} is not a file but a {mode:?}", file.display()) } // found a file EntryMode::Blob | EntryMode::BlobExecutable => Ok(tree_entry.object_id()), } }