manifest: rename Cursor to DfsCursor

Summary: Signal more clearly that the iteration in the cursor is depth first.

Reviewed By: quark-zju

Differential Revision: D18843135

fbshipit-source-id: 8ee2c612963eaf6fec3ae48f75ebf16bd177fed4

eden/scm/lib/manifest/src/tree/iter.rs

@@ -93,7 +93,7 @@ impl<'a> Iterator for BfsIter<'a> {
 /// Because this structure intends to back iterators, it is designed so that `step()` is called on
 /// every invocation of `next()`. This should simplify iterator implementations what may want to
 /// return the root of the subtree that is being iterated.
-pub struct Cursor<'a> {
+pub struct DfsCursor<'a> {
     state: State,
     store: &'a InnerStore,
     path: RepoPathBuf,
@@ -121,10 +121,10 @@ enum State {
     Done,
 }
 
-impl<'a> Cursor<'a> {
+impl<'a> DfsCursor<'a> {
     /// Default constructor for Cursor.
     pub fn new(store: &'a InnerStore, path: RepoPathBuf, link: &'a Link) -> Self {
-        Cursor {
+        DfsCursor {
             state: State::Init,
             store,
             path,
@@ -172,7 +172,7 @@ impl<'a> Cursor<'a> {
     }
 }
 
-impl<'a> Cursor<'a> {
+impl<'a> DfsCursor<'a> {
     /// Advances the cursor towards a new [`Link`]. Visiting is done in pre-order.
     /// Errors are an interesting topic. At the time of this writing errors only appear when
     /// computing [`DurableEntry`] (which cache their failures). To protect against potential

eden/scm/lib/manifest/src/tree/mod.rs

@@ -31,7 +31,7 @@ pub(crate) use self::link::Link;
 pub use self::{diff::Diff, store::TreeStore};
 use crate::{
     tree::{
-        iter::{BfsIter, Cursor, Step},
+        iter::{BfsIter, DfsCursor, Step},
         link::{DirLink, Durable, DurableEntry, Ephemeral, Leaf},
         store::InnerStore,
     },
@@ -90,8 +90,8 @@ impl Tree {
         }
     }
 
-    fn root_cursor<'a>(&'a self) -> Cursor<'a> {
-        Cursor::new(&self.store, RepoPathBuf::new(), &self.root)
+    fn root_cursor<'a>(&'a self) -> DfsCursor<'a> {
+        DfsCursor::new(&self.store, RepoPathBuf::new(), &self.root)
     }
 }
 
@@ -374,7 +374,7 @@ impl Tree {
             store: &'a InnerStore,
             path: RepoPathBuf,
             converted_nodes: Vec<(RepoPathBuf, HgId, Bytes, HgId, HgId)>,
-            parent_trees: Vec<Cursor<'a>>,
+            parent_trees: Vec<DfsCursor<'a>>,
         };
         impl<'a> Executor<'a> {
             fn new(store: &'a InnerStore, parent_trees: &[&'a Tree]) -> Result<Executor<'a>> {
@@ -1174,7 +1174,7 @@ mod tests {
 
     #[test]
     fn test_cursor_skip() {
-        fn step<'a>(cursor: &mut Cursor<'a>) {
+        fn step<'a>(cursor: &mut DfsCursor<'a>) {
             match cursor.step() {
                 Step::Success => (),
                 Step::End => panic!("reached the end too soon"),