Move git related things into specialized git crate

Co-Authored-By: Mikayla Maki <mikayla@zed.dev>

crates/git/src/repository.rs

@@ -0,0 +1,95 @@
+use anyhow::Result;
+use git2::Repository as LibGitRepository;
+use parking_lot::Mutex;
+use std::{path::Path, sync::Arc};
+use util::ResultExt;
+
+#[derive(Clone)]
+pub struct GitRepository {
+    // Path to folder containing the .git file or directory
+    content_path: Arc<Path>,
+    // Path to the actual .git folder.
+    // Note: if .git is a file, this points to the folder indicated by the .git file
+    git_dir_path: Arc<Path>,
+    scan_id: usize,
+    libgit_repository: Arc<Mutex<LibGitRepository>>,
+}
+
+impl GitRepository {
+    pub fn open(dotgit_path: &Path) -> Option<GitRepository> {
+        LibGitRepository::open(&dotgit_path)
+            .log_err()
+            .and_then(|libgit_repository| {
+                Some(Self {
+                    content_path: libgit_repository.workdir()?.into(),
+                    git_dir_path: dotgit_path.canonicalize().log_err()?.into(),
+                    scan_id: 0,
+                    libgit_repository: Arc::new(parking_lot::Mutex::new(libgit_repository)),
+                })
+            })
+    }
+
+    pub fn manages(&self, path: &Path) -> bool {
+        path.canonicalize()
+            .map(|path| path.starts_with(&self.content_path))
+            .unwrap_or(false)
+    }
+
+    pub fn in_dot_git(&self, path: &Path) -> bool {
+        path.canonicalize()
+            .map(|path| path.starts_with(&self.git_dir_path))
+            .unwrap_or(false)
+    }
+
+    pub fn content_path(&self) -> &Path {
+        self.content_path.as_ref()
+    }
+
+    pub fn git_dir_path(&self) -> &Path {
+        self.git_dir_path.as_ref()
+    }
+
+    pub fn scan_id(&self) -> usize {
+        self.scan_id
+    }
+
+    pub fn set_scan_id(&mut self, scan_id: usize) {
+        println!("setting scan id");
+        self.scan_id = scan_id;
+    }
+
+    pub async fn load_head_text(&self, relative_file_path: &Path) -> Option<String> {
+        fn logic(repo: &LibGitRepository, relative_file_path: &Path) -> Result<Option<String>> {
+            let object = repo
+                .head()?
+                .peel_to_tree()?
+                .get_path(relative_file_path)?
+                .to_object(&repo)?;
+
+            let content = match object.as_blob() {
+                Some(blob) => blob.content().to_owned(),
+                None => return Ok(None),
+            };
+
+            let head_text = String::from_utf8(content.to_owned())?;
+            Ok(Some(head_text))
+        }
+
+        match logic(&self.libgit_repository.as_ref().lock(), relative_file_path) {
+            Ok(value) => return value,
+            Err(err) => log::error!("Error loading head text: {:?}", err),
+        }
+        None
+    }
+}
+
+impl std::fmt::Debug for GitRepository {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        f.debug_struct("GitRepository")
+            .field("content_path", &self.content_path)
+            .field("git_dir_path", &self.git_dir_path)
+            .field("scan_id", &self.scan_id)
+            .field("libgit_repository", &"LibGitRepository")
+            .finish()
+    }
+}