impl From<char> for WhichHandle

Author: ctrlcctrlv

src/point.rs

@@ -290,11 +290,21 @@ impl FromStr for PointType {
 impl FromStr for WhichHandle {
     type Err = ();
     fn from_str(s: &str) -> Result<WhichHandle, ()> {
-        Ok(match s.trim() {
-            "A" | "a" => WhichHandle::A,
-            "B" | "b" => WhichHandle::B,
-            _ => WhichHandle::Neither,
-        })
+        debug_assert!(s.chars().count() == 1);
+        s.trim().chars().nth(0).map(|c| Ok(c.into())).unwrap_or(Err(()))
+    }
+}
+
+impl From<char> for WhichHandle {
+    fn from(c: char) -> WhichHandle {
+        match c {
+            'A' | 'a' | 'Ａ' | 'ａ' => WhichHandle::A,
+            'B' | 'b' | 'Ｂ' | 'ｂ' => WhichHandle::B,
+            _ => {
+                debug_assert!(c == 0 as char);
+                WhichHandle::Neither
+            },
+        }
     }
 }
 

tests/handle.rs

@@ -15,3 +15,32 @@ fn test_handles() {
     assert_eq!(wh.opposite(), WhichHandle::B);
     assert_eq!(wh.opposite().opposite(), WhichHandle::A);
 }
+
+#[test]
+fn test_which_handle() {
+    let wh1: WhichHandle = 'A'.into();
+    assert_eq!(wh1, WhichHandle::A);
+    let wh1: WhichHandle = 'Ａ'.into();
+    assert_eq!(wh1, WhichHandle::A);
+    let wh1: WhichHandle = "Ａ".into();
+    assert_eq!(wh1, WhichHandle::A);
+    let wh1: WhichHandle = "b".into();
+    assert_eq!(wh1, WhichHandle::B);
+    let wh1: WhichHandle = '\u{0}'.into();
+    assert_eq!(wh1, WhichHandle::Neither);
+}
+
+#[cfg(not(debug_assertions))]
+#[test]
+fn test_which_handle_nonstrict() {
+    use std::str::FromStr as _;
+
+    let wh1: WhichHandle = " b ".into();
+    assert_eq!(wh1, WhichHandle::B);
+    let wh1: WhichHandle = 'C'.into();
+    assert_eq!(wh1, WhichHandle::Neither);
+    let wh1 = WhichHandle::from_str("");
+    assert!(wh1.is_err());
+    let wh1 = WhichHandle::from_str("   BBBB  ");
+    assert_eq!(wh1, Ok(WhichHandle::B));
+}