Merge pull request #13 from Sajjon/try_update_with

Try update with

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "identified_vec"
-version = "0.1.9"
+version = "0.1.10"
 edition = "2021"
 authors = ["Alexander Cyon <[email protected]>"]
 description = "Like HashSet but retaining INSERTION order and without `Hash` requirement on the Element type."

src/vec/identified_vec.rs

@@ -486,6 +486,22 @@ where
         true
     }
 
+    #[allow(unused_mut)]
+    #[inline]
+    fn try_update_with<F, Er>(&mut self, id: &I, mut mutate: F) -> Result<bool, Er>
+    where
+        F: FnMut(E) -> Result<E, Er>,
+    {
+        if !self.contains_id(id) {
+            return Ok(false);
+        }
+        let mut existing = self.elements.remove(id).expect("Element for existing id");
+        mutate(existing).map(|updated| {
+            self.elements.insert(id.clone(), updated);
+            true
+        })
+    }
+
     /// Try to update the given element to the `identified_vec` if a element with the same ID is already present.
     ///
     /// - Parameter item: The value to append or replace.

src/vec/is_identified_vec.rs

@@ -145,6 +145,10 @@ where
     where
         F: FnMut(&mut Element);
 
+    fn try_update_with<F, Er>(&mut self, id: &ID, mutate: F) -> Result<bool, Er>
+    where
+        F: FnMut(Element) -> Result<Element, Er>;
+
     /// Insert a new member to this identified_vec at the specified index, if the identified_vec doesn't already contain
     /// it.
     ///

src/vec_of/is_identified_vec_of_via.rs

@@ -178,6 +178,19 @@ where
         self.via_mut().update_with(id, mutate)
     }
 
+    #[allow(unused_mut)]
+    #[inline]
+    fn try_update_with<F, Er>(
+        &mut self,
+        id: &<Element as Identifiable>::ID,
+        mut mutate: F,
+    ) -> Result<bool, Er>
+    where
+        F: FnMut(Element) -> Result<Element, Er>,
+    {
+        self.via_mut().try_update_with(id, mutate)
+    }
+
     #[inline]
     fn try_append_new(&mut self, element: Element) -> Result<(bool, usize), Error> {
         self.via_mut().try_append_new(element)

tests/tests.rs

@@ -404,6 +404,36 @@ fn update_with() {
     assert_eq!(sut.update_with(&999, |_| panic!("not called")), false);
 }
 
+#[test]
+fn try_update_with_contains() {
+    let mut sut = Users::new();
+    sut.append(User::new(2, "Blob, Jr."));
+    assert_eq!(
+        sut.try_update_with(&2, |x| {
+            let mut y = x;
+            *y.name.get_mut() = "Junior, Jr.".to_string();
+            Result::<User, ()>::Ok(y)
+        }),
+        Ok(true)
+    );
+    assert_eq!(sut.items(), [User::new(2, "Junior, Jr.")]);
+}
+
+#[test]
+fn try_update_with_not_contains() {
+    let mut sut = Users::new();
+    sut.append(User::new(2, "Blob, Jr."));
+    assert_eq!(
+        sut.try_update_with(&999, |x| {
+            let mut y = x;
+            *y.name.get_mut() = "Will never happen.".to_string();
+            Result::<User, ()>::Ok(y)
+        }),
+        Ok(false)
+    );
+    assert_eq!(sut.items(), [User::new(2, "Blob, Jr.")]);
+}
+
 #[test]
 #[should_panic(expected = "Expected element at index {index}")]
 fn update_at_expect_panic_unknown_index() {