From dbe9f878c920aaddb1db5c287cb5e30e453dba59 Mon Sep 17 00:00:00 2001
From: Lukas Friman <lukas@dreamplay.net>
Date: Tue, 22 Jul 2025 15:59:43 +0200
Subject: [PATCH 1/2] feat(core): Infallible error types.

---
 xmlity/src/types/infallible.rs | 51 ++++++++++++++++++++++++++++++++++
 xmlity/src/types/mod.rs        |  1 +
 2 files changed, 52 insertions(+)
 create mode 100644 xmlity/src/types/infallible.rs

diff --git a/xmlity/src/types/infallible.rs b/xmlity/src/types/infallible.rs
new file mode 100644
index 0000000..7d19724
--- /dev/null
+++ b/xmlity/src/types/infallible.rs
@@ -0,0 +1,51 @@
+use std::convert::Infallible;
+
+impl crate::de::Error for Infallible {
+    fn custom<T>(msg: T) -> Self
+    where
+        T: std::fmt::Display,
+    {
+        panic!("Infallible error: {}", msg);
+    }
+
+    fn wrong_name(name: &crate::ExpandedName<'_>, expected: &crate::ExpandedName<'_>) -> Self {
+        panic!("Infallible error: wrong name \"{name}\", expected \"{expected}\"");
+    }
+
+    fn unexpected_visit<T>(unexpected: crate::de::Unexpected, _expected: &T) -> Self {
+        panic!("Infallible error: unexpected visit of {unexpected}");
+    }
+
+    fn missing_field(field: &str) -> Self {
+        panic!("Infallible error: missing field {field}");
+    }
+
+    fn no_possible_variant(ident: &str) -> Self {
+        panic!("Infallible error: no possible variant {ident}");
+    }
+
+    fn missing_data() -> Self {
+        panic!("Infallible error: missing data");
+    }
+
+    fn unknown_child() -> Self {
+        panic!("Infallible error: unknown child");
+    }
+
+    fn invalid_string() -> Self {
+        panic!("Infallible error: invalid string");
+    }
+}
+
+impl crate::ser::Error for Infallible {
+    fn custom<T>(msg: T) -> Self
+    where
+        T: std::fmt::Display,
+    {
+        panic!("Infallible error: {}", msg);
+    }
+
+    fn unexpected_serialize(unexpected: crate::ser::Unexpected) -> Self {
+        panic!("Infallible error: unexpected serialize of {unexpected}");
+    }
+}
diff --git a/xmlity/src/types/mod.rs b/xmlity/src/types/mod.rs
index 8e4121b..3965ca8 100644
--- a/xmlity/src/types/mod.rs
+++ b/xmlity/src/types/mod.rs
@@ -3,6 +3,7 @@
 //! It also contains some visitors for the types which can be reused, including [`iterator::IteratorVisitor`].
 
 pub mod common;
+mod infallible;
 pub mod iterator;
 mod primitive;
 mod smart;

From c64ece5aa3f50b08966745fd1ed940c1068436e6 Mon Sep 17 00:00:00 2001
From: Lukas Friman <lukas@dreamplay.net>
Date: Tue, 22 Jul 2025 16:01:55 +0200
Subject: [PATCH 2/2] `cargo clippy`

---
 xmlity/src/types/infallible.rs | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/xmlity/src/types/infallible.rs b/xmlity/src/types/infallible.rs
index 7d19724..bf06d13 100644
--- a/xmlity/src/types/infallible.rs
+++ b/xmlity/src/types/infallible.rs
@@ -5,7 +5,7 @@ impl crate::de::Error for Infallible {
     where
         T: std::fmt::Display,
     {
-        panic!("Infallible error: {}", msg);
+        panic!("Infallible error: {msg}");
     }
 
     fn wrong_name(name: &crate::ExpandedName<'_>, expected: &crate::ExpandedName<'_>) -> Self {
@@ -42,7 +42,7 @@ impl crate::ser::Error for Infallible {
     where
         T: std::fmt::Display,
     {
-        panic!("Infallible error: {}", msg);
+        panic!("Infallible error: {msg}");
     }
 
     fn unexpected_serialize(unexpected: crate::ser::Unexpected) -> Self {