Workaround a uuid bump breaking change

(This needs a cargo nightly feature so we cannot do this now, but as
soon as this hit's stable)

diesel/Cargo.toml

@@ -24,6 +24,7 @@ serde_json = { version = ">=0.8.0, <2.0", optional = true }
 time = { version = "0.1", optional = true }
 url = { version = "1.4.0", optional = true }
 uuid = { version = ">=0.2.0, <0.7.0", optional = true, features = ["use_std"] }
+uuidv07 = { version = "0.7.0", optional = true, package = "uuid"}
 ipnetwork = { version = ">=0.12.2, <0.14.0", optional = true }
 num-bigint = { version = ">=0.1.41, <0.3", optional = true }
 num-traits = { version = "0.2", optional = true }

diesel/src/pg/types/uuid_v0_7.rs

@@ -0,0 +1,59 @@
+extern crate uuidv07 as uuid;
+
+use std::io::prelude::*;
+
+use deserialize::{self, FromSql};
+use pg::Pg;
+use serialize::{self, IsNull, Output, ToSql};
+use sql_types::Uuid;
+
+#[derive(FromSqlRow, AsExpression)]
+#[diesel(foreign_derive)]
+#[sql_type = "Uuid"]
+#[allow(dead_code)]
+struct UuidProxy(uuid::Uuid);
+
+impl FromSql<Uuid, Pg> for uuid::Uuid {
+    fn from_sql(bytes: Option<&[u8]>) -> deserialize::Result<Self> {
+        let bytes = not_none!(bytes);
+        uuid::Uuid::from_slice(bytes).map_err(|e| e.into())
+    }
+}
+
+impl ToSql<Uuid, Pg> for uuid::Uuid {
+    fn to_sql<W: Write>(&self, out: &mut Output<W, Pg>) -> serialize::Result {
+        out.write_all(self.as_bytes())
+            .map(|_| IsNull::No)
+            .map_err(Into::into)
+    }
+}
+
+#[test]
+fn uuid_to_sql() {
+    let mut bytes = Output::test();
+    let test_uuid = uuid::Uuid::from_fields(0xFFFF_FFFF, 0xFFFF, 0xFFFF, b"abcdef12").unwrap();
+    ToSql::<Uuid, Pg>::to_sql(&test_uuid, &mut bytes).unwrap();
+    assert_eq!(bytes, test_uuid.as_bytes());
+}
+
+#[test]
+fn some_uuid_from_sql() {
+    let input_uuid = uuid::Uuid::from_fields(0xFFFF_FFFF, 0xFFFF, 0xFFFF, b"abcdef12").unwrap();
+    let output_uuid = FromSql::<Uuid, Pg>::from_sql(Some(input_uuid.as_bytes())).unwrap();
+    assert_eq!(input_uuid, output_uuid);
+}
+
+#[test]
+fn bad_uuid_from_sql() {
+    let uuid = uuid::Uuid::from_sql(Some(b"boom"));
+    assert_eq!(uuid.unwrap_err().description(), "UUID parse error");
+}
+
+#[test]
+fn no_uuid_from_sql() {
+    let uuid = uuid::Uuid::from_sql(None);
+    assert_eq!(
+        uuid.unwrap_err().description(),
+        "Unexpected null for non-null column"
+    );
+}