From 11c07ec06b40127098ca4c041a432a5cced6574a Mon Sep 17 00:00:00 2001
From: Martin Larralde <martin.larralde@embl.de>
Date: Sun, 3 Mar 2024 22:46:34 +0100
Subject: [PATCH] Test `Box` derive for sized and unsized types

---
 .../fails/unsized_type_self_receiver.rs        | 18 ++++++++++++++++++
 .../fails/unsized_type_self_receiver.stderr    | 12 ++++++++++++
 tests/derive_box/successes/unsized_type.rs     | 18 ++++++++++++++++++
 3 files changed, 48 insertions(+)
 create mode 100644 tests/derive_box/fails/unsized_type_self_receiver.rs
 create mode 100644 tests/derive_box/fails/unsized_type_self_receiver.stderr
 create mode 100644 tests/derive_box/successes/unsized_type.rs

diff --git a/tests/derive_box/fails/unsized_type_self_receiver.rs b/tests/derive_box/fails/unsized_type_self_receiver.rs
new file mode 100644
index 0000000..a2095c9
--- /dev/null
+++ b/tests/derive_box/fails/unsized_type_self_receiver.rs
@@ -0,0 +1,18 @@
+use blanket::blanket;
+use impls::impls;
+
+#[blanket(derive(Box))]
+pub trait StringLike {
+    fn into_utf8(self) -> Vec<u8>;
+}
+
+impl StringLike for str {
+    fn into_utf8(self) -> Vec<u8> {
+        self.as_bytes().into()
+    }
+}
+
+fn main() {
+    assert!(impls!(str:      StringLike));
+    assert!(impls!(Box<str>: StringLike));
+}
diff --git a/tests/derive_box/fails/unsized_type_self_receiver.stderr b/tests/derive_box/fails/unsized_type_self_receiver.stderr
new file mode 100644
index 0000000..e3c5208
--- /dev/null
+++ b/tests/derive_box/fails/unsized_type_self_receiver.stderr
@@ -0,0 +1,12 @@
+error[E0277]: the size for values of type `str` cannot be known at compilation time
+  --> tests/derive_box/fails/unsized_type_self_receiver.rs:10:18
+   |
+10 |     fn into_utf8(self) -> Vec<u8> {
+   |                  ^^^^ doesn't have a size known at compile-time
+   |
+   = help: the trait `Sized` is not implemented for `str`
+   = help: unsized fn params are gated as an unstable feature
+help: function arguments must have a statically known size, borrowed types always have a known size
+   |
+10 |     fn into_utf8(&self) -> Vec<u8> {
+   |                  +
diff --git a/tests/derive_box/successes/unsized_type.rs b/tests/derive_box/successes/unsized_type.rs
new file mode 100644
index 0000000..ee8d180
--- /dev/null
+++ b/tests/derive_box/successes/unsized_type.rs
@@ -0,0 +1,18 @@
+use blanket::blanket;
+use impls::impls;
+
+#[blanket(derive(Box))]
+pub trait StringLike {
+    fn is_utf8(&self) -> bool;
+}
+
+impl StringLike for str {
+    fn is_utf8(&self) -> bool {
+        true
+    }
+}
+
+fn main() {
+    assert!(impls!(str:      StringLike));
+    assert!(impls!(Box<str>: StringLike));
+}