New VFS API

crates/vfs/src/vfs_path.rs

@@ -0,0 +1,49 @@
+//! Abstract-ish representation of paths for VFS.
+use std::fmt;
+
+use paths::{AbsPath, AbsPathBuf};
+
+/// Long-term, we want to support files which do not reside in the file-system,
+/// so we treat VfsPaths as opaque identifiers.
+#[derive(Debug, Clone, Ord, PartialOrd, Eq, PartialEq, Hash)]
+pub struct VfsPath(VfsPathRepr);
+
+impl VfsPath {
+    pub fn as_path(&self) -> Option<&AbsPath> {
+        match &self.0 {
+            VfsPathRepr::PathBuf(it) => Some(it.as_path()),
+        }
+    }
+    pub fn join(&self, path: &str) -> VfsPath {
+        match &self.0 {
+            VfsPathRepr::PathBuf(it) => {
+                let res = it.join(path).normalize();
+                VfsPath(VfsPathRepr::PathBuf(res))
+            }
+        }
+    }
+    pub fn pop(&mut self) -> bool {
+        match &mut self.0 {
+            VfsPathRepr::PathBuf(it) => it.pop(),
+        }
+    }
+}
+
+#[derive(Debug, Clone, Ord, PartialOrd, Eq, PartialEq, Hash)]
+enum VfsPathRepr {
+    PathBuf(AbsPathBuf),
+}
+
+impl From<AbsPathBuf> for VfsPath {
+    fn from(v: AbsPathBuf) -> Self {
+        VfsPath(VfsPathRepr::PathBuf(v))
+    }
+}
+
+impl fmt::Display for VfsPath {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        match &self.0 {
+            VfsPathRepr::PathBuf(it) => fmt::Display::fmt(&it.display(), f),
+        }
+    }
+}