From ff2ea63a63231163885ad8da6d2a83a8c6b64445 Mon Sep 17 00:00:00 2001
From: Sean Griffin <sean@seantheprogrammer.com>
Date: Sun, 20 Dec 2015 11:42:17 -0700
Subject: [PATCH] Ensure `Vec<T>` can be used in `#[changeset_for]`

Usually we implement all the various `AsExpression` for refs in the
`expression_impls!` macro. However, that macro doesn't work with generics,
and we forgot to handle `Vec<T>` (I think I figured the slice impl was
enough for some reason).

I tried to write a test for this change, but there are actually several
other bugs that prevent me from testing this properly. See #65 & #66.

Fixes #63.
---
 CHANGELOG.md                    |  5 +++++
 diesel/src/types/impls/array.rs | 11 +++++++++++
 2 files changed, 16 insertions(+)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index c2dee297171f..1af9981b3497 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -12,6 +12,11 @@ for Rust libraries in [RFC #1105](https://github.com/rust-lang/rfcs/blob/master/
 * Add print_sql! and debug_sql! macros to print out and return sql strings from
   QueryFragments.
 
+### Fixed
+
+* `#[changeset_for]` can now be used with structs containing a `Vec`. Fixes
+  [#63](https://github.com/sgrif/diesel/issues/63).
+
 ## [0.3.0] 2015-12-04
 
 ### Changed
diff --git a/diesel/src/types/impls/array.rs b/diesel/src/types/impls/array.rs
index 08263b94abe5..2db28d9f659c 100644
--- a/diesel/src/types/impls/array.rs
+++ b/diesel/src/types/impls/array.rs
@@ -90,6 +90,17 @@ impl<ST, T> AsExpression<Array<ST>> for Vec<T> where
     }
 }
 
+impl<'a, ST, T> AsExpression<Array<ST>> for &'a Vec<T> where
+    ST: NativeSqlType,
+    T: ToSql<ST>,
+{
+    type Expression = Bound<Array<ST>, Self>;
+
+    fn as_expression(self) -> Self::Expression {
+        Bound::new(self)
+    }
+}
+
 impl<'a, ST, T> ToSql<Array<ST>> for &'a [T] where
     ST: NativeSqlType,
     T: ToSql<ST>,