Implement Default and From<T> for PosValue<T>

Author: amirbou

binrw/src/pos_value.rs

@@ -94,3 +94,21 @@ impl<U, T: PartialEq<U>> PartialEq<U> for PosValue<T> {
         self.val == *other
     }
 }
+
+impl<T: Default> Default for PosValue<T> {
+    fn default() -> Self {
+        Self {
+            val: Default::default(),
+            pos: Default::default(),
+        }
+    }
+}
+
+impl<T> From<T> for PosValue<T> {
+    fn from(val: T) -> Self {
+        Self {
+            val,
+            pos: Default::default(),
+        }
+    }
+}

binrw/tests/pos_value.rs

@@ -5,7 +5,7 @@ use binrw::{io::Cursor, BinRead, BinReaderExt, BinWrite, PosValue};
 
 #[test]
 fn pos_value() {
-    #[derive(BinRead, BinWrite)]
+    #[derive(BinRead, BinWrite, Default)]
     struct MyType {
         a: u16,
         b: PosValue<u8>,
@@ -28,4 +28,15 @@ fn pos_value() {
     val.write_be(&mut Cursor::new(&mut output)).unwrap();
 
     assert_eq!(output, b"\xFF\xFE\x01");
+    let default_val = MyType::default();
+    assert_eq!(default_val.a, u16::default());
+    assert_eq!(*default_val.b, u8::default());
+    assert_eq!(default_val.b.pos, u64::default());
+
+    let from = MyType {
+        a: val.a,
+        b: (*val.b).into(),
+    };
+    assert_eq!(from.a, val.a);
+    assert_eq!(from.b, *val.b);
 }