add PathDir::current_dir

Cargo.toml

@@ -13,7 +13,7 @@ license = "MIT OR Apache-2.0"
 name = "path_abs"
 readme = "README.md"
 repository = "https://github.com/vitiral/path_abs"
-version = "0.3.15"
+version = "0.3.16"
 
 [dependencies]
 std_prelude = "0.2.12"

src/dir.rs

@@ -37,6 +37,25 @@ impl PathDir {
         PathDir::from_abs(abs)
     }
 
+    /// Returns the current working directory from the `env` as a `PathDir`.
+    ///
+    /// # Examples
+    /// ```rust
+    /// # extern crate path_abs;
+    /// use path_abs::PathDir;
+    /// # fn try_main() -> ::std::io::Result<()> {
+    /// let cwd = PathDir::current_dir()?;
+    /// # let env_cwd = ::std::fs::canonicalize(::std::env::current_dir()?)?;
+    /// # let cwd_ref: &::std::path::PathBuf = cwd.as_ref();
+    /// # assert_eq!(cwd_ref, &env_cwd);
+    /// # Ok(()) } fn main() { try_main().unwrap() }
+    /// ```
+    pub fn current_dir() -> Result<PathDir> {
+        let dir = ::std::env::current_dir()
+            .map_err(|err| Error::new(err, "getting current_dir", PathArc::new("$CWD")))?;
+        PathDir::new(dir)
+    }
+
     /// Consume the `PathAbs` validating that the path is a directory and returning `PathDir`. The
     /// directory must exist or `io::Error` will be returned.
     ///
@@ -69,6 +88,7 @@ impl PathDir {
         }
     }
 
+
     #[inline(always)]
     /// Do the conversion _without checking_.
     ///