From c8f3364c742c3528ee0709a44e82643fee2f8afe Mon Sep 17 00:00:00 2001
From: Mx Kookie <kookie@spacekookie.de>
Date: Wed, 6 Jan 2021 23:04:53 +0100
Subject: octopus: supergit: add interface to query specific store paths

---
 apps/servers/octopus/supergit/src/files/tree.rs | 104 ++++++++++++++++++++++++
 1 file changed, 104 insertions(+)
 create mode 100644 apps/servers/octopus/supergit/src/files/tree.rs

(limited to 'apps/servers/octopus/supergit/src/files/tree.rs')

diff --git a/apps/servers/octopus/supergit/src/files/tree.rs b/apps/servers/octopus/supergit/src/files/tree.rs
new file mode 100644
index 000000000000..5f4fb6671aa5
--- /dev/null
+++ b/apps/servers/octopus/supergit/src/files/tree.rs
@@ -0,0 +1,104 @@
+//! Low-level abstraction over finding refs inside a commit tree
+
+use super::tree_utils as utils;
+use crate::HashId;
+use git2::{ObjectType, Repository, TreeWalkMode, TreeWalkResult};
+use std::sync::Arc;
+
+/// A git directory tree walker abstraction
+///
+/// This type is meant to be used ephemerally, and internally uses the
+/// libgit2 `Tree` abstraction to walk directory trees lazily to
+/// resolve paths to [`TreeEntry`](self::TreeEntry)'s.
+///
+/// Note: this type _may_ be removed in the future.  For a more
+/// high-level (and stable) API, check
+/// [`Explorer`](crate::files::Explorer)
+pub struct FileTree {
+    repo: Arc<Repository>,
+    c: HashId,
+}
+
+impl FileTree {
+    /// Construct a new FileTree with a repository
+    pub(crate) fn new(repo: Arc<Repository>, c: HashId) -> Self {
+        Self { repo, c }
+    }
+
+    /// Resolve a path inside this file tree
+    ///
+    /// Will return `None` if there is no tree for the selected
+    /// commit, or the file inside the tree does not exist.
+    pub fn resolve(&self, path: &str) -> Option<TreeEntry> {
+        let tree = utils::open_tree(&self.repo, &self.c)?;
+        let target = utils::path_split(path);
+
+        // Initialise entry to None as a fallback
+        let mut entry = None;
+
+        // Walk over tree and swallor errors (which we use to
+        // terminace traversal to speed up indexing time)
+        let _ = tree.walk(TreeWalkMode::PreOrder, |p, e| {
+            if utils::path_cmp(&target, p, e.name().unwrap()) {
+                entry = Some(TreeEntry::new(p, &e));
+                TreeWalkResult::Ok
+            } else {
+                TreeWalkResult::Skip
+            }
+        });
+
+        // Return whatever the entry is now
+        entry
+    }
+}
+
+/// An entry in a commit tree
+///
+/// This type is lazily loaded, and can represent either a Blob or a
+/// Directory.  You can resolve its value by calling
+/// [`resolve()`](Self::resolve)
+pub struct TreeEntry {
+    tt: EntryType,
+    id: HashId,
+    path: String,
+}
+
+impl TreeEntry {
+    fn new(path: &str, entry: &git2::TreeEntry) -> Self {
+        let tt = match entry.kind() {
+            Some(ObjectType::Blob) => EntryType::File,
+            Some(ObjectType::Tree) => EntryType::Dir,
+            _ => unimplemented!(),
+        };
+        let id = entry.id().into();
+        let path = path.into();
+
+        Self { tt, id, path }
+    }
+
+    /// Resolve this type to a [`Yield`]()
+    pub fn resolve(&self) {}
+}
+
+/// Type of a TreeEntry
+pub enum EntryType {
+    /// A file that can be loaded
+    File,
+    /// A directory that can be indexed
+    Dir,
+}
+
+#[test]
+fn index_tree() {
+    let path = env!("CARGO_MANIFEST_DIR").to_owned() + "/test-repo";
+    use crate::Repository as Repo;
+
+    eprintln!("Path: `{}`", path);
+
+    let r = Repo::open(&path).unwrap();
+    let b = r.branch("master".into()).unwrap();
+    let h = b.head();
+
+    let t = h.tree();
+    t.resolve("README".into()).unwrap();
+}
-- 
cgit v1.2.3