Vendor things

third-party/vendor/num_enum/tests/unsafe_from_primitive.rs

@@ -0,0 +1,82 @@
+use ::num_enum::UnsafeFromPrimitive;
+
+// Guard against https://github.com/illicitonion/num_enum/issues/27
+mod alloc {}
+mod core {}
+mod num_enum {}
+mod std {}
+
+#[test]
+fn has_unsafe_from_primitive_number() {
+    #[derive(Debug, Eq, PartialEq, UnsafeFromPrimitive)]
+    #[repr(u8)]
+    enum Enum {
+        Zero,
+        One,
+    }
+
+    unsafe {
+        assert_eq!(Enum::unchecked_transmute_from(0_u8), Enum::Zero);
+        assert_eq!(Enum::unchecked_transmute_from(1_u8), Enum::One);
+    }
+}
+
+#[test]
+fn has_unsafe_from_primitive_number_with_alternatives_and_default_which_are_ignored() {
+    #[derive(Debug, Eq, PartialEq, UnsafeFromPrimitive)]
+    #[repr(u8)]
+    enum Enum {
+        Zero,
+        One,
+        #[num_enum(alternatives = [3, 4])]
+        Some,
+        #[num_enum(default)]
+        Many = 5,
+    }
+
+    unsafe {
+        assert_eq!(Enum::unchecked_transmute_from(0_u8), Enum::Zero);
+        assert_eq!(Enum::unchecked_transmute_from(1_u8), Enum::One);
+        assert_eq!(Enum::unchecked_transmute_from(2_u8), Enum::Some);
+        assert_eq!(Enum::unchecked_transmute_from(5_u8), Enum::Many);
+        // Any other conversions would be undefined behavior.
+    }
+
+    #[allow(deprecated)]
+    unsafe {
+        assert_eq!(Enum::from_unchecked(0_u8), Enum::Zero);
+        assert_eq!(Enum::from_unchecked(1_u8), Enum::One);
+        assert_eq!(Enum::from_unchecked(2_u8), Enum::Some);
+        assert_eq!(Enum::from_unchecked(5_u8), Enum::Many);
+    }
+}
+
+#[test]
+fn has_unsafe_from_primitive_number_with_alternatives_and_std_default_which_are_ignored() {
+    #[derive(Debug, Default, Eq, PartialEq, UnsafeFromPrimitive)]
+    #[repr(u8)]
+    enum Enum {
+        Zero,
+        One,
+        #[num_enum(alternatives = [3, 4])]
+        Some,
+        #[default]
+        Many = 5,
+    }
+
+    unsafe {
+        assert_eq!(Enum::unchecked_transmute_from(0_u8), Enum::Zero);
+        assert_eq!(Enum::unchecked_transmute_from(1_u8), Enum::One);
+        assert_eq!(Enum::unchecked_transmute_from(2_u8), Enum::Some);
+        assert_eq!(Enum::unchecked_transmute_from(5_u8), Enum::Many);
+        // Any other conversions would be undefined behavior.
+    }
+
+    #[allow(deprecated)]
+    unsafe {
+        assert_eq!(Enum::from_unchecked(0_u8), Enum::Zero);
+        assert_eq!(Enum::from_unchecked(1_u8), Enum::One);
+        assert_eq!(Enum::from_unchecked(2_u8), Enum::Some);
+        assert_eq!(Enum::from_unchecked(5_u8), Enum::Many);
+    }
+}