rust-dirs-multiset: use `AsRef` instead of concrete types when possible

I also renamed `vec` to `dirstate`, because it was not a great name.

Differential Revision: https://phab.mercurial-scm.org/D7524

rust/hg-core/src/dirstate/dirs_multiset.rs

@@ -1,334 +1,341 b''
 // dirs_multiset.rs
 //
 // Copyright 2019 Raphaël Gomès <[e-mail]>
 //
 // This software may be used and distributed according to the terms of the
 // GNU General Public License version 2 or any later version.
 
 //! A multiset of directory names.
 //!
 //! Used to counts the references to directories in a manifest or dirstate.
 use crate::utils::hg_path::{HgPath, HgPathBuf};
 use crate::{
     dirstate::EntryState, utils::files, DirstateEntry, DirstateMapError,
     FastHashMap,
 };
 use std::collections::hash_map::{self, Entry};
 
 // could be encapsulated if we care API stability more seriously
 pub type DirsMultisetIter<'a> = hash_map::Keys<'a, HgPathBuf, u32>;
 
 #[derive(PartialEq, Debug)]
 pub struct DirsMultiset {
     inner: FastHashMap<HgPathBuf, u32>,
 }
 
 impl DirsMultiset {
     /// Initializes the multiset from a dirstate.
     ///
     /// If `skip_state` is provided, skips dirstate entries with equal state.
     pub fn from_dirstate(
-        vec: &FastHashMap<HgPathBuf, DirstateEntry>,
+        dirstate: &FastHashMap<HgPathBuf, DirstateEntry>,
         skip_state: Option<EntryState>,
     ) -> Self {
         let mut multiset = DirsMultiset {
             inner: FastHashMap::default(),
         };
 
-        for (filename, DirstateEntry { state, .. }) in vec {
+        for (filename, DirstateEntry { state, .. }) in dirstate {
             // This `if` is optimized out of the loop
             if let Some(skip) = skip_state {
                 if skip != *state {
                     multiset.add_path(filename);
                 }
             } else {
                 multiset.add_path(filename);
             }
         }
 
         multiset
     }
 
     /// Initializes the multiset from a manifest.
-    pub fn from_manifest(vec: &Vec<HgPathBuf>) -> Self {
+    pub fn from_manifest(manifest: &[impl AsRef<HgPath>]) -> Self {
         let mut multiset = DirsMultiset {
             inner: FastHashMap::default(),
         };
 
-        for filename in vec {
-            multiset.add_path(filename);
+        for filename in manifest {
+            multiset.add_path(filename.as_ref());
         }
 
         multiset
     }
 
     /// Increases the count of deepest directory contained in the path.
     ///
     /// If the directory is not yet in the map, adds its parents.
-    pub fn add_path(&mut self, path: &HgPath) -> Result<(), DirstateMapError> {
-        for subpath in files::find_dirs(path) {
+    pub fn add_path(
+        &mut self,
+        path: impl AsRef<HgPath>,
+    ) -> Result<(), DirstateMapError> {
+        for subpath in files::find_dirs(path.as_ref()) {
             if subpath.as_bytes().last() == Some(&b'/') {
                 // TODO Remove this once PathAuditor is certified
                 // as the only entrypoint for path data
                 return Err(DirstateMapError::ConsecutiveSlashes);
             }
             if let Some(val) = self.inner.get_mut(subpath) {
                 *val += 1;
                 break;
             }
             self.inner.insert(subpath.to_owned(), 1);
         }
         Ok(())
     }
 
     /// Decreases the count of deepest directory contained in the path.
     ///
     /// If it is the only reference, decreases all parents until one is
     /// removed.
     /// If the directory is not in the map, something horrible has happened.
     pub fn delete_path(
         &mut self,
-        path: &HgPath,
+        path: impl AsRef<HgPath>,
     ) -> Result<(), DirstateMapError> {
-        for subpath in files::find_dirs(path) {
+        for subpath in files::find_dirs(path.as_ref()) {
             match self.inner.entry(subpath.to_owned()) {
                 Entry::Occupied(mut entry) => {
                     let val = entry.get().clone();
                     if val > 1 {
                         entry.insert(val - 1);
                         break;
                     }
                     entry.remove();
                 }
                 Entry::Vacant(_) => {
                     return Err(DirstateMapError::PathNotFound(
-                        path.to_owned(),
+                        path.as_ref().to_owned(),
                     ))
                 }
             };
         }
 
         Ok(())
     }
 
-    pub fn contains(&self, key: &HgPath) -> bool {
-        self.inner.contains_key(key)
+    pub fn contains(&self, key: impl AsRef<HgPath>) -> bool {
+        self.inner.contains_key(key.as_ref())
     }
 
     pub fn iter(&self) -> DirsMultisetIter {
         self.inner.keys()
     }
 
     pub fn len(&self) -> usize {
         self.inner.len()
     }
 }
 
 #[cfg(test)]
 mod tests {
     use super::*;
 
     #[test]
     fn test_delete_path_path_not_found() {
-        let mut map = DirsMultiset::from_manifest(&vec![]);
+        let manifest: Vec<HgPathBuf> = vec![];
+        let mut map = DirsMultiset::from_manifest(&manifest);
         let path = HgPathBuf::from_bytes(b"doesnotexist/");
         assert_eq!(
             Err(DirstateMapError::PathNotFound(path.to_owned())),
             map.delete_path(&path)
         );
     }
 
     #[test]
     fn test_delete_path_empty_path() {
         let mut map = DirsMultiset::from_manifest(&vec![HgPathBuf::new()]);
         let path = HgPath::new(b"");
         assert_eq!(Ok(()), map.delete_path(path));
         assert_eq!(
             Err(DirstateMapError::PathNotFound(path.to_owned())),
             map.delete_path(path)
         );
     }
 
     #[test]
     fn test_delete_path_successful() {
         let mut map = DirsMultiset {
             inner: [("", 5), ("a", 3), ("a/b", 2), ("a/c", 1)]
                 .iter()
                 .map(|(k, v)| (HgPathBuf::from_bytes(k.as_bytes()), *v))
                 .collect(),
         };
 
         assert_eq!(Ok(()), map.delete_path(HgPath::new(b"a/b/")));
         eprintln!("{:?}", map);
         assert_eq!(Ok(()), map.delete_path(HgPath::new(b"a/b/")));
         eprintln!("{:?}", map);
         assert_eq!(
             Err(DirstateMapError::PathNotFound(HgPathBuf::from_bytes(
                 b"a/b/"
             ))),
             map.delete_path(HgPath::new(b"a/b/"))
         );
 
         assert_eq!(2, *map.inner.get(HgPath::new(b"a")).unwrap());
         assert_eq!(1, *map.inner.get(HgPath::new(b"a/c")).unwrap());
         eprintln!("{:?}", map);
         assert_eq!(Ok(()), map.delete_path(HgPath::new(b"a/")));
         eprintln!("{:?}", map);
 
         assert_eq!(Ok(()), map.delete_path(HgPath::new(b"a/c/")));
         assert_eq!(
             Err(DirstateMapError::PathNotFound(HgPathBuf::from_bytes(
                 b"a/c/"
             ))),
             map.delete_path(HgPath::new(b"a/c/"))
         );
     }
 
     #[test]
     fn test_add_path_empty_path() {
-        let mut map = DirsMultiset::from_manifest(&vec![]);
+        let manifest: Vec<HgPathBuf> = vec![];
+        let mut map = DirsMultiset::from_manifest(&manifest);
         let path = HgPath::new(b"");
         map.add_path(path);
 
         assert_eq!(1, map.len());
     }
 
     #[test]
     fn test_add_path_successful() {
-        let mut map = DirsMultiset::from_manifest(&vec![]);
+        let manifest: Vec<HgPathBuf> = vec![];
+        let mut map = DirsMultiset::from_manifest(&manifest);
 
         map.add_path(HgPath::new(b"a/"));
         assert_eq!(1, *map.inner.get(HgPath::new(b"a")).unwrap());
         assert_eq!(1, *map.inner.get(HgPath::new(b"")).unwrap());
         assert_eq!(2, map.len());
 
         // Non directory should be ignored
         map.add_path(HgPath::new(b"a"));
         assert_eq!(1, *map.inner.get(HgPath::new(b"a")).unwrap());
         assert_eq!(2, map.len());
 
         // Non directory will still add its base
         map.add_path(HgPath::new(b"a/b"));
         assert_eq!(2, *map.inner.get(HgPath::new(b"a")).unwrap());
         assert_eq!(2, map.len());
 
         // Duplicate path works
         map.add_path(HgPath::new(b"a/"));
         assert_eq!(3, *map.inner.get(HgPath::new(b"a")).unwrap());
 
         // Nested dir adds to its base
         map.add_path(HgPath::new(b"a/b/"));
         assert_eq!(4, *map.inner.get(HgPath::new(b"a")).unwrap());
         assert_eq!(1, *map.inner.get(HgPath::new(b"a/b")).unwrap());
 
         // but not its base's base, because it already existed
         map.add_path(HgPath::new(b"a/b/c/"));
         assert_eq!(4, *map.inner.get(HgPath::new(b"a")).unwrap());
         assert_eq!(2, *map.inner.get(HgPath::new(b"a/b")).unwrap());
 
         map.add_path(HgPath::new(b"a/c/"));
         assert_eq!(1, *map.inner.get(HgPath::new(b"a/c")).unwrap());
 
         let expected = DirsMultiset {
             inner: [("", 2), ("a", 5), ("a/b", 2), ("a/b/c", 1), ("a/c", 1)]
                 .iter()
                 .map(|(k, v)| (HgPathBuf::from_bytes(k.as_bytes()), *v))
                 .collect(),
         };
         assert_eq!(map, expected);
     }
 
     #[test]
     fn test_dirsmultiset_new_empty() {
-        let new = DirsMultiset::from_manifest(&vec![]);
+        let manifest: Vec<HgPathBuf> = vec![];
+        let new = DirsMultiset::from_manifest(&manifest);
         let expected = DirsMultiset {
             inner: FastHashMap::default(),
         };
         assert_eq!(expected, new);
 
         let new = DirsMultiset::from_dirstate(&FastHashMap::default(), None);
         let expected = DirsMultiset {
             inner: FastHashMap::default(),
         };
         assert_eq!(expected, new);
     }
 
     #[test]
     fn test_dirsmultiset_new_no_skip() {
-        let input_vec = ["a/", "b/", "a/c", "a/d/"]
+        let input_vec: Vec<HgPathBuf> = ["a/", "b/", "a/c", "a/d/"]
             .iter()
             .map(|e| HgPathBuf::from_bytes(e.as_bytes()))
             .collect();
         let expected_inner = [("", 2), ("a", 3), ("b", 1), ("a/d", 1)]
             .iter()
             .map(|(k, v)| (HgPathBuf::from_bytes(k.as_bytes()), *v))
             .collect();
 
         let new = DirsMultiset::from_manifest(&input_vec);
         let expected = DirsMultiset {
             inner: expected_inner,
         };
         assert_eq!(expected, new);
 
         let input_map = ["a/", "b/", "a/c", "a/d/"]
             .iter()
             .map(|f| {
                 (
                     HgPathBuf::from_bytes(f.as_bytes()),
                     DirstateEntry {
                         state: EntryState::Normal,
                         mode: 0,
                         mtime: 0,
                         size: 0,
                     },
                 )
             })
             .collect();
         let expected_inner = [("", 2), ("a", 3), ("b", 1), ("a/d", 1)]
             .iter()
             .map(|(k, v)| (HgPathBuf::from_bytes(k.as_bytes()), *v))
             .collect();
 
         let new = DirsMultiset::from_dirstate(&input_map, None);
         let expected = DirsMultiset {
             inner: expected_inner,
         };
         assert_eq!(expected, new);
     }
 
     #[test]
     fn test_dirsmultiset_new_skip() {
         let input_map = [
             ("a/", EntryState::Normal),
             ("a/b/", EntryState::Normal),
             ("a/c", EntryState::Removed),
             ("a/d/", EntryState::Merged),
         ]
         .iter()
         .map(|(f, state)| {
             (
                 HgPathBuf::from_bytes(f.as_bytes()),
                 DirstateEntry {
                     state: *state,
                     mode: 0,
                     mtime: 0,
                     size: 0,
                 },
             )
         })
         .collect();
 
         // "a" incremented with "a/c" and "a/d/"
         let expected_inner = [("", 1), ("a", 2), ("a/d", 1)]
             .iter()
             .map(|(k, v)| (HgPathBuf::from_bytes(k.as_bytes()), *v))
             .collect();
 
         let new =
             DirsMultiset::from_dirstate(&input_map, Some(EntryState::Normal));
         let expected = DirsMultiset {
             inner: expected_inner,
         };
         assert_eq!(expected, new);
     }
 }