src/extname.rs in faster_path-0.3.7 vs src/extname.rs in faster_path-0.3.8

@@ -1,63 +1,25 @@
-use path_parsing::SEP;
 use std::str;
+use path_parsing::{SEP, find_last_non_sep_pos};
 
-struct ExtnameCoords {
-  word: bool,
-  pred: bool,
-  dot: bool,
-  start: usize,
-  end: usize,
-}
-
-impl ExtnameCoords {
-  pub fn dec(&mut self) {
-    self.start -= 1;
-    if !self.word {
-      self.end -= 1;
-    }
-  }
-}
-
-pub fn extname(pth: &str) -> &str {
-  let path = pth.as_bytes();
-  let mut extname = ExtnameCoords {
-    word: false,
-    pred: false,
-    dot: false,
-    start: path.len(),
-    end: path.len(),
+pub fn extname(path: &str) -> &str {
+  let end = match find_last_non_sep_pos(path.as_bytes()) {
+    Some(pos) => pos + 1,
+    _ => return "",
   };
-
-  for &item in path.iter().rev() {
-    if (item == b'.' && !extname.dot) || item == SEP {
-      if item == SEP && extname.word {
-        return ""
+  let bytes = &path.as_bytes()[..end];
+  for (pos, c) in bytes.iter().enumerate().rev() {
+    match *c {
+      b'.' => {
+        let prev = bytes.get(pos - 1);
+        if pos == end - 1 || prev == None || prev == Some(&SEP) {
+          return "";
+        } else {
+          return &path[pos..end]
+        };
       }
-
-      if !extname.pred {
-        extname.dec();
-      }
-
-      if extname.word {
-        extname.dot = true;
-      }
-    } else {
-      if extname.dot {
-        extname.pred = true;
-        break;
-      } else {
-        extname.word = true;
-      }
-
-      if !extname.pred {
-        extname.dec()
-      }
+      SEP => return "",
+      _ => {}
     }
-  }
-
-  if !extname.pred {
-    return "";
-  }
-
-  str::from_utf8(&path[extname.start..extname.end]).unwrap_or("")
+  };
+  ""
 }